CYCLIC NUCLEOTIDE ANALOGS

[0001] This application claims the benefit of U.S. Provisional Application Nos. 61/536,445, filed Sep. 19, 2011; and 61/426,471, filed Dec. 22, 2010; both of which are incorporated herein by reference in their entirety; including any drawings.

[0002] 1. Field

[0003] The present application relates to the fields of chemistry, biochemistry and medicine. More particularly, disclosed herein are cyclic nucleotide analogs, pharmaceutical compositions that include one or more cyclic nucleotide analogs and methods of synthesizing the same. Also disclosed herein are methods of treating diseases and/or conditions with cyclic nucleotide analogs alone or in combination therapy with other agents.

[0004] 2. Description

[0005] Nucleoside analogs are a class of compounds that have been shown to exert antiviral and anticancer activity both in vitro and in vivo, and thus, have been the subject of widespread research for the treatment of viral infections and cancer. Nucleoside analogs are usually therapeutically inactive compounds that are converted by host or viral enzymes to their respective active anti-metabolites, which, in turn, may inhibit polymerases involved in viral or cell proliferation. The activation occurs by a variety of mechanisms, such as the addition of one or more phosphate groups and, or in combination with, other metabolic processes.

[0006] Some embodiments disclosed herein relate to a compound of Formula (I) or a pharmaceutically acceptable salt thereof.

[0007] Some embodiments disclosed herein relate to methods of ameliorating and/or treating a neoplastic disease that can include administering to a subject suffering from the neoplastic disease a therapeutically effective amount of one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof. Other embodiments described herein relate to using one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, in the manufacture of a medicament for ameliorating and/or treating a neoplastic disease. Still other embodiments described herein relate to one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, that can be used for ameliorating and/or treating a neoplastic disease.

[0008] Some embodiments disclosed herein relate to methods of inhibiting the growth of a tumor that can include administering to a subject having a tumor a therapeutically effective amount of one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof. Other embodiments described herein relate to using one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, in the manufacture of a medicament for inhibiting the growth of a tumor. Still other embodiments described herein relate to one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, that can be used for inhibiting the growth of a tumor.

[0009] Some embodiments disclosed herein relate to methods of ameliorating and/or treating a viral infection that can include administering to a subject suffering from the viral infection a therapeutically effective amount of one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof. Other embodiments described herein relate to using one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, in the manufacture of a medicament for ameliorating and/or treating a viral infection. Still other embodiments described herein relate to one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, that can be used for ameliorating and/or treating a viral infection.

[0010] Some embodiments disclosed herein relate to methods of ameliorating and/or treating a viral infection that can include contacting a cell infected with the virus with an effective amount of one or more compounds described herein, or a pharmaceutically acceptable salt of one or more compounds described herein, or a pharmaceutical composition that includes one or more compounds described herein, or a pharmaceutically acceptable salt thereof. Other embodiments described herein relate to using one or more compounds described herein, or a pharmaceutically acceptable salt of one or more compounds described herein, in the manufacture of a medicament for ameliorating and/or treating a viral infection that can include contacting a cell infected with the virus with an effective amount of said compound(s). Still other embodiments described herein relate to one or more compounds described herein, or a pharmaceutically acceptable salt of one or more compounds described herein, or a pharmaceutical composition that includes one or more compounds described herein, or a pharmaceutically acceptable salt thereof, that can be used for ameliorating and/or treating a viral infection by contacting a cell infected with the virus with an effective amount of said compound(s).

[0011] Some embodiments disclosed herein relate to methods of inhibiting replication of a virus that can include contacting a cell infected with the virus with an effective amount of one or more compounds described herein, or a pharmaceutically acceptable salt of one or more compounds described herein, or a pharmaceutical composition that includes one or more compounds described herein, or a pharmaceutically acceptable salt thereof. Other embodiments described herein relate to using one or more compounds described herein, or a pharmaceutically acceptable salt of one or more compounds described herein, in the manufacture of a medicament for inhibiting replication of a virus that can include contacting a cell infected with the virus with an effective amount of said compound(s). Still other embodiments described herein relate to one or more compounds described herein, or a pharmaceutically acceptable salt of one or more compounds described herein, or a pharmaceutical composition that includes one or more compounds described herein, or a pharmaceutically acceptable salt thereof, that can be used for inhibiting replication of a virus by contacting a cell infected with the virus with an effective amount of said compound(s).

[0012] Some embodiments disclosed herein relate to methods of ameliorating and/or treating a parasitic disease that can include administering to a subject suffering from the parasitic disease a therapeutically effective amount of one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof. Other embodiments described herein relate to using one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, in the manufacture of a medicament for ameliorating and/or treating a parasitic disease. Still other embodiments described herein relate to one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof, that can be used for ameliorating and/or treating a parasitic disease.

[0013] Some embodiments disclosed herein relate to methods of ameliorating and/or treating a viral infection that can include administering to a subject suffering from the viral infection a therapeutically effective amount of a compound described herein or a pharmaceutically acceptable salt thereof (for example, one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof), or a pharmaceutical composition that includes a compound described herein, in combination with an agent selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an other antiviral compound, a compound of Formula (AA), a mono-, di- and/or tri-phosphate thereof, a compound of Formula (CC), and a compound of Formula (DD), or a pharmaceutically acceptable salt or any of the foregoing. Some embodiments disclosed herein relate to methods of ameliorating and/or treating a viral infection that can include contacting a cell infected with the viral infection with a therapeutically effective amount of a compound described herein or a pharmaceutically acceptable salt thereof (for example, one or more compounds of Formula (I), or a pharmaceutically acceptable salt thereof), or a pharmaceutical composition that includes a compound described herein, in combination with an agent selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an other antiviral compound, a compound of Formula (AA), a mono-, di- and/or tri-phosphate thereof, a compound of Formula (CC), and a compound of Formula (DD), or a pharmaceutically acceptable salt of any of the foregoing. Some embodiments disclosed herein relate to methods of inhibiting replication of a virus that can include administering to a subject a therapeutically effective amount of a compound described herein or a pharmaceutically acceptable salt thereof (for example, a compound of Formula (I), or a pharmaceutically acceptable salt thereof), or a pharmaceutical composition that includes a compound described herein, or a pharmaceutically acceptable salt thereof, in combination with an agent selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an other antiviral compound, a compound of Formula (AA), a mono-, di- and/or tri-phosphate thereof, a compound of Formula (CC), and a compound of Formula (DD), or a pharmaceutically acceptable salt of any of the foregoing. In some embodiments, the agent can be a compound, or a pharmaceutically acceptable salt thereof, selected from Compound 1001-1014, 2001-2010, 3001-3008, 4001-4005, 5001-5002, 6000-6078, 7000-7077 or 9000, or a pharmaceutical composition that includes one or more of the aforementioned compounds, or pharmaceutically acceptable salt thereof. In some embodiments, the method can include administering a second agent selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an other antiviral compound, a compound of Formula (AA), a mono-, di- and/or tri-phosphate thereof, a compound of Formula (CC), and a compound of Formula (DD), or a pharmaceutically acceptable salt of any of the foregoing. In some embodiments, the viral infection can be HCV.

[0023] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of ordinary skill in the art. All patents, applications, published applications and other publications referenced herein are incorporated by reference in their entirety unless stated otherwise. In the event that there are a plurality of definitions for a term herein, those in this section prevail unless stated otherwise.

[0024] As used herein, any “R” group(s) such as, without limitation, R, R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, R¹², R¹³, R¹⁴, R¹⁵, R¹⁶, R¹⁷, R¹⁸, R¹⁹, R²⁰, R²¹, R²², R^1A, R^2A, R^3A, R^3B, R^4A, R^5A, R^6A, R^7A, and R^8A represent substituents that can be attached to the indicated atom. An R group may be substituted or unsubstituted. If two “R” groups are described as being “taken together” the R groups and the atoms they are attached to can form a cycloalkyl, cycloalkenyl, aryl, heteroaryl or heterocycle. For example, without limitation, if R¹⁸ and R¹⁹ of an —C(R¹⁸)(R¹⁹)— group are indicated to be “taken together,” it means that they are covalently bonded to one another to form a ring:

[0025] Whenever a group is described as being “optionally substituted” that group may be unsubstituted or substituted with one or more of the indicated substituents. Likewise, when a group is described as being “unsubstituted or substituted” if substituted, the substituent(s) may be selected from one or more the indicated substituents. If no substituents are indicated, it is meant that the indicated “optionally substituted” or “substituted” group may be substituted with one or more group(s) individually and independently selected from alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, heteroaralkyl, (heteroalicyclyl)alkyl, hydroxy, protected hydroxyl, alkoxy, aryloxy, acyl, mercapto, alkylthio, arylthio, cyano, halogen, thiocarbonyl, O-carbamyl, N-carbamyl, O-thiocarbamyl, N-thiocarbamyl, C-amido, N-amido, S-sulfonamido, N-sulfonamido, C-carboxy, protected C-carboxy, O-carboxy, isocyanato, thiocyanato, isothiocyanato, nitro, silyl, sulfenyl, sulfinyl, sulfonyl, haloalkyl, haloalkoxy, trihalomethanesulfonyl, trihalomethanesulfonamido, an amino, a mono-substituted amino and a di-substituted amino group, and protected derivatives thereof.

[0026] As used herein, “C_a to C_b” in which “a” and “b” are integers refer to the number of carbon atoms in an alkyl, alkenyl or alkynyl group, or the number of carbon atoms in the ring of a cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl or heteroalicyclyl group. That is, the alkyl, alkenyl, alkynyl, ring of the cycloalkyl, ring of the cycloalkenyl, ring of the cycloalkynyl, ring of the aryl, ring of the heteroaryl or ring of the heteroalicyclyl can contain from “a” to “b”, inclusive, carbon atoms. Thus, for example, a “C₁ to C₄ alkyl” group refers to all alkyl groups having from 1 to 4 carbons, that is, CH₃—, CH₃CH₂—, CH₃CH₂CH₂—, (CH₃)₂CH—, CH₃CH₂CH₂CH₂—, CH₃CH₂CH(CH₃)— and (CH₃)₃C—. If no “a” and “b” are designated with regard to an alkyl, alkenyl, alkynyl, cycloalkyl cycloalkenyl, cycloalkynyl, aryl, heteroaryl or heteroalicyclyl group, the broadest range described in these definitions is to be assumed.

[0027] As used herein, “alkyl” refers to a straight or branched hydrocarbon chain that comprises a fully saturated (no double or triple bonds) hydrocarbon group. The alkyl group may have 1 to 20 carbon atoms (whenever it appears herein, a numerical range such as “1 to 20” refers to each integer in the given range; e.g., “1 to 20 carbon atoms” means that the alkyl group may consist of 1 carbon atom, 2 carbon atoms, 3 carbon atoms, etc., up to and including 20 carbon atoms, although the present definition also covers the occurrence of the term “alkyl” where no numerical range is designated). The alkyl group may also be a medium size alkyl having 1 to 10 carbon atoms. The alkyl group could also be a lower alkyl having 1 to 6 carbon atoms. The alkyl group of the compounds may be designated as “C₁-C₄ alkyl” or similar designations. By way of example only, “C₁-C₄ alkyl” indicates that there are one to four carbon atoms in the alkyl chain, i.e., the alkyl chain is selected from methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, and t-butyl. Typical alkyl groups include, but are in no way limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl, pentyl and hexyl. The alkyl group may be substituted or unsubstituted.

[0028] As used herein, “alkenyl” refers to an alkyl group that contains in the straight or branched hydrocarbon chain one or more double bonds. An alkenyl group may be unsubstituted or substituted.

[0029] As used herein, “alkynyl” refers to an alkyl group that contains in the straight or branched hydrocarbon chain one or more triple bonds. An alkynyl group may be unsubstituted or substituted.

[0030] As used herein, “cycloalkyl” refers to a completely saturated (no double or triple bonds) mono- or multi-cyclic hydrocarbon ring system. When composed of two or more rings, the rings may be joined together in a fused fashion. Cycloalkyl groups can contain 3 to 10 atoms in the ring(s) or 3 to 8 atoms in the ring(s). A cycloalkyl group may be unsubstituted or substituted. Typical cycloalkyl groups include, but are in no way limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl.

[0031] As used herein, “cycloalkenyl” refers to a mono- or multi-cyclic hydrocarbon ring system that contains one or more double bonds in at least one ring; although, if there is more than one, the double bonds cannot form a fully delocalized pi-electron system throughout all the rings (otherwise the group would be “aryl,” as defined herein). When composed of two or more rings, the rings may be connected together in a fused fashion. A cycloalkenyl group may be unsubstituted or substituted.

[0032] As used herein, “cycloalkynyl” refers to a mono- or multi-cyclic hydrocarbon ring system that contains one or more triple bonds in at least one ring. If there is more than one triple bond, the triple bonds cannot form a fully delocalized pi-electron system throughout all the rings. When composed of two or more rings, the rings may be joined together in a fused fashion. A cycloalkynyl group may be unsubstituted or substituted.

[0033] As used herein, “aryl” refers to a carbocyclic (all carbon) monocyclic or multicyclic aromatic ring system (including fused ring systems where two carbocyclic rings share a chemical bond) that has a fully delocalized pi-electron system throughout all the rings. The number of carbon atoms in an aryl group can vary. For example, the aryl group can be a C₆-C₁₄ aryl group, a C₆-C₁₀ aryl group, or a C₆ aryl group. Examples of aryl groups include, but are not limited to, benzene, naphthalene and azulene. An aryl group may be substituted or unsubstituted.

[0034] As used herein, “heteroaryl” refers to a monocyclic or multicyclic aromatic ring system (a ring system with fully delocalized pi-electron system) that contain(s) one or more heteroatoms, that is, an element other than carbon, including but not limited to, nitrogen, oxygen and sulfur. The number of atoms in the ring(s) of a heteroaryl group can vary. For example, the heteroaryl group can contain 4 to 14 atoms in the ring(s), 5 to 10 atoms in the ring(s) or 5 to 6 atoms in the ring(s). Furthermore, the term “heteroaryl” includes fused ring systems where two rings, such as at least one aryl ring and at least one heteroaryl ring, or at least two heteroaryl rings, share at least one chemical bond. Examples of heteroaryl rings include, but are not limited to, furan, furazan, thiophene, benzothiophene, phthalazine, pyrrole, oxazole, benzoxazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, thiazole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, benzothiazole, imidazole, benzimidazole, indole, indazole, pyrazole, benzopyrazole, isoxazole, benzoisoxazole, isothiazole, triazole, benzotriazole, thiadiazole, tetrazole, pyridine, pyridazine, pyrimidine, pyrazine, purine, pteridine, quinoline, isoquinoline, quinazoline, quinoxaline, cinnoline, and triazine. A heteroaryl group may be substituted or unsubstituted.

[0035] As used herein, “heterocyclyl” or “heteroalicyclyl” refers to three-, four-, five-, six-, seven-, eight-, nine-, ten-, up to 18-membered monocyclic, bicyclic, and tricyclic ring system wherein carbon atoms together with from 1 to 5 heteroatoms constitute said ring system. A heterocycle may optionally contain one or more unsaturated bonds situated in such a way, however, that a fully delocalized pi-electron system does not occur throughout all the rings. The heteroatom(s) is an element other than carbon including, but not limited to, oxygen, sulfur, and nitrogen. A heterocycle may further contain one or more carbonyl or thiocarbonyl functionalities, so as to make the definition include oxo-systems and thio-systems such as lactams, lactones, cyclic imides, cyclic thioimides and cyclic carbamates. When composed of two or more rings, the rings may be joined together in a fused fashion. Additionally, any nitrogens in a heteroalicyclic may be quaternized. Heterocyclyl or heteroalicyclic groups may be unsubstituted or substituted. Examples of such “heterocyclyl” or “heteroalicyclyl” groups include but are not limited to, 1,3-dioxin, 1,3-dioxane, 1,4-dioxane, 1,2-dioxolane, 1,3-dioxolane, 1,4-dioxolane, 1,3-oxathiane, 1,4-oxathiin, 1,3-oxathiolane, 1,3-dithiole, 1,3-dithiolane, 1,4-oxathiane, tetrahydro-1,4-thiazine, 2H-1,2-oxazine, maleimide, succinimide, barbituric acid, thiobarbituric acid, dioxopiperazine, hydantoin, dihydrouracil, trioxane, hexahydro-1,3,5-triazine, imidazoline, imidazolidine, isoxazoline, isoxazolidine, oxazoline, oxazolidine, oxazolidinone, thiazoline, thiazolidine, morpholine, oxirane, piperidine N-Oxide, piperidine, piperazine, pyrrolidine, pyrrolidone, pyrrolidione, 4-piperidone, pyrazoline, pyrazolidine, 2-oxopyrrolidine, tetrahydropyran, 4H-pyran, tetrahydrothiopyran, thiamorpholine, thiamorpholine sulfoxide, thiamorpholine sulfone, and their benzo-fused analogs (e.g., benzimidazolidinone, tetrahydroquinoline, 3,4-methylenedioxyphenyl).

[0036] As used herein, “aralkyl” and “aryl(alkyl)” refer to an aryl group connected, as a substituent, via a lower alkylene group. The lower alkylene and aryl group of an aralkyl may be substituted or unsubstituted. Examples include but are not limited to benzyl, 2-phenylalkyl, 3-phenylalkyl, and naphthylalkyl.

[0037] As used herein, “heteroaralkyl” and “heteroaryl(alkyl)” refer to a heteroaryl group connected, as a substituent, via a lower alkylene group. The lower alkylene and heteroaryl group of heteroaralkyl may be substituted or unsubstituted. Examples include but are not limited to 2-thienylalkyl, 3-thienylalkyl, furylalkyl, thienylalkyl, pyrrolylalkyl, pyridylalkyl, isoxazolylalkyl, and imidazolylalkyl, and their benzo-fused analogs.

[0038] A “(heteroalicyclyl)alkyl” and “(heterocyclyl)alkyl” refer to a heterocyclic or a heteroalicyclylic group connected, as a substituent, via a lower alkylene group. The lower alkylene and heterocyclyl of a (heteroalicyclyl)alkyl may be substituted or unsubstituted. Examples include but are not limited tetrahydro-2H-pyran-4-yl)methyl, (piperidin-4-yl)ethyl, (piperidin-4-yl)propyl, (tetrahydro-2H-thiopyran-4-yl)methyl, and (1,3-thiazinan-4-yl)methyl.

[0039] “Lower alkylene groups” are straight-chained —CH₂— tethering groups, forming bonds to connect molecular fragments via their terminal carbon atoms. Examples include but are not limited to methylene (—CH₂—), ethylene (—CH₂CH₂—), propylene (—CH₂CH₂CH₂—), and butylene (—CH₂CH₂CH₂CH₂—). A lower alkylene group can be substituted by replacing one or more hydrogen of the lower alkylene group with a substituent(s) listed under the definition of “substituted.”

[0040] As used herein, “alkoxy” refers to the formula —OR wherein R is an alkyl, an alkenyl, an alkynyl, a cycloalkyl, a cycloalkenyl or a cycloalkynyl is defined as above. A non-limiting list of alkoxys are methoxy, ethoxy, n-propoxy, 1-methylethoxy (isopropoxy), n-butoxy, iso-butoxy, sec-butoxy, tert-butoxy, and the like. An alkoxy may be substituted or unsubstituted.

[0041] As used herein, “acyl” refers to a hydrogen, alkyl, alkenyl, alkynyl, or aryl connected, as substituents, via a carbonyl group. Examples include formyl, acetyl, propanoyl, benzoyl, and acryl. An acyl may be substituted or unsubstituted.

[0042] As used herein, “hydroxyalkyl” refers to an alkyl group in which one or more of the hydrogen atoms are replaced by a hydroxy group. Exemplary hydroxyalkyl groups include but are not limited to, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, and 2,2-dihydroxyethyl. A hydroxyalkyl may be substituted or unsubstituted.

[0043] As used herein, “haloalkyl” refers to an alkyl group in which one or more of the hydrogen atoms are replaced by a halogen (e.g., mono-haloalkyl, di-haloalkyl and tri-haloalkyl). Such groups include but are not limited to, chloromethyl, fluoromethyl, difluoromethyl, trifluoromethyl, 1-chloro-2-fluoromethyl and 2-fluoroisobutyl. A haloalkyl may be substituted or unsubstituted.

[0044] As used herein, “haloalkoxy” refers to an alkoxy group in which one or more of the hydrogen atoms are replaced by a halogen (e.g., mono-haloalkoxy, di-haloalkoxy and tri-haloalkoxy). Such groups include but are not limited to, chloromethoxy, fluoromethoxy, difluoromethoxy, trifluoromethoxy, 1-chloro-2-fluoromethoxy and 2-fluoroisobutoxy. A haloalkoxy may be substituted or unsubstituted.

[0045] As used herein, “aryloxy” and “arylthio” refers to RO— and RS—, in which R is an aryl, such as, but not limited to, phenyl. Both an aryloxy and arylthio may be substituted or unsubstituted.

[0046] A “sulfenyl” group refers to an “—SR” group in which R can be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl. A sulfenyl may be substituted or unsubstituted.

[0047] A “sulfinyl” group refers to an “—S(═O)—R” group in which R can be the same as defined with respect to sulfenyl. A sulfinyl may be substituted or unsubstituted.

[0048] A “sulfonyl” group refers to an “SO₂R” group in which R can be the same as defined with respect to sulfenyl. A sulfonyl may be substituted or unsubstituted.

[0049] An “O-carboxy” group refers to a “RC(═O)O—” group in which R can be hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl, as defined herein. An O-carboxy may be substituted or unsubstituted.

[0050] The terms “ester” and “C-carboxy” refer to a “—C(═O)OR” group in which R can be the same as defined with respect to O-carboxy. An ester and C-carboxy may be substituted or unsubstituted.

[0051] A “thiocarbonyl” group refers to a “—C(═S)R” group in which R can be the same as defined with respect to O-carboxy. A thiocarbonyl may be substituted or unsubstituted.

[0052] A “trihalomethanesulfonyl” group refers to an “X₃CSO₂—” group wherein each X is a halogen.

[0053] A “trihalomethanesulfonamido” group refers to an “X₃CS(O)₂N(R_A)—” group wherein each X is a halogen, and R_A hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl.

[0054] The term “amino” as used herein refers to a —NH₂ group.

[0055] As used herein, the term “hydroxy” refers to a —OH group.

[0056] A “cyano” group refers to a “—CN” group.

[0057] The term “azido” as used herein refers to a —N₃ group.

[0058] The term “allenyl” as used herein refers to a R₂C═C═CR— group in which each R can be independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heterocyclyl, aralkyl, or (heterocyclyl)alkyl.

[0059] An “isocyanato” group refers to a “—NCO” group.

[0060] A “thiocyanato” group refers to a “—CNS” group.

[0061] An “isothiocyanato” group refers to an “—NCS” group.

[0062] A “mercapto” group refers to an “—SH” group.

[0063] A “carbonyl” group refers to a C═O group.

[0064] An “S-sulfonamido” group refers to a “—SO₂N(R_AR_B)” group in which R_A and R_B can be independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl. An S-sulfonamido may be substituted or unsubstituted.

[0065] An “N-sulfonamido” group refers to a “RSO₂N(R_A)—” group in which R and R_A can be independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl. An N-sulfonamido may be substituted or unsubstituted.

[0066] An “O-carbamyl” group refers to a “—OC(═O)N(R_AR_B)” group in which R_A and R_B can be independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl. An O-carbamyl may be substituted or unsubstituted.

[0067] An “N-carbamyl” group refers to an “ROC(═O)N(R_A)—” group in which R and R_A can be independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl. An N-carbamyl may be substituted or unsubstituted.

[0068] An “O-thiocarbamyl” group refers to a “—OC(═S)—N(R_AR_B)” group in which R_A and R_B can be independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl. An O-thiocarbamyl may be substituted or unsubstituted.

[0069] An “N-thiocarbamyl” group refers to an “ROC(═S)N(R_A)—” group in which R and R_A can be independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl. An N-thiocarbamyl may be substituted or unsubstituted.

[0070] A “C-amido” group refers to a “—C(═O)N(R_AR_B)” group in which R_A and R_B can be independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl. A C-amido may be substituted or unsubstituted.

[0071] An “N-amido” group refers to a “RC(═O)N(R_A)—” group in which R and R_A can be independently hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, heteroaryl, heteroalicyclyl, aralkyl, or (heteroalicyclyl)alkyl. An N-amido may be substituted or unsubstituted.

[0072] The term “halogen atom” or “halogen” as used herein, means any one of the radio-stable atoms of column 7 of the Periodic Table of the Elements, such as, fluorine, chlorine, bromine and iodine.

[0073] Where the numbers of substituents is not specified (e.g., haloalkyl), there may be one or more substituents present. For example “haloalkyl” may include one or more of the same or different halogens. As another example, “C₁-C₃ alkoxyphenyl” may include one or more of the same or different alkoxy groups containing one, two or three atoms.

[0074] As used herein, the abbreviations for any protective groups, amino acids and other compounds, are, unless indicated otherwise, in accord with their common usage, recognized abbreviations, or the IUPAC-IUB Commission on Biochemical Nomenclature (See, Biochem. 11:942-944 (1972)).

[0075] The term “nucleoside” is used herein in its ordinary sense as understood by those skilled in the art, and refers to a compound composed of an optionally substituted pentose moiety or modified pentose moiety attached to a heterocyclic base or tautomer thereof via a N-glycosidic bond, such as attached via the 9-position of a purine-base or the 1-position of a pyrimidine-base. Examples include, but are not limited to, a ribonucleoside comprising a ribose moiety and a deoxyribonucleoside comprising a deoxyribose moiety. A modified pentose moiety is a pentose moiety in which an oxygen atom has been replaced with a carbon and/or a carbon has been replaced with a sulfur or an oxygen atom. A “nucleoside” is a monomer that can have a substituted base and/or sugar moiety. Additionally, a nucleoside can be incorporated into larger DNA and/or RNA polymers and oligomers. In some instances, the nucleoside can be a nucleoside analog drug.

[0076] As used herein, the term “heterocyclic base” refers to an optionally substituted nitrogen-containing heterocyclyl that can be attached to an optionally substituted pentose moiety or modified pentose moiety. In some embodiments, the heterocyclic base can be selected from an optionally substituted purine-base, an optionally substituted pyrimidine-base and an optionally substituted triazole-base (for example, a 1,2,4-triazole). The term “purine-base” is used herein in its ordinary sense as understood by those skilled in the art, and includes its tautomers. Similarly, the term “pyrimidine-base” is used herein in its ordinary sense as understood by those skilled in the art, and includes its tautomers. A non-limiting list of optionally substituted purine-bases includes purine, adenine, guanine, hypoxanthine, xanthine, alloxanthine, 7-alkylguanine (e.g., 7-methylguanine), theobromine, caffeine, uric acid and isoguanine. Examples of pyrimidine-bases include, but are not limited to, cytosine, thymine, uracil, 5,6-dihydrouracil and 5-alkylcytosine (e.g., 5-methylcytosine). An example of an optionally substituted triazole-base is 1,2,4-triazole-3-carboxamide. Other non-limiting examples of heterocyclic bases include diaminopurine, 8-oxo-N⁶-alkyladenine (e.g., 8-oxo-N⁶-methyladenine), 7-deazaxanthine, 7-deazaguanine, 7-deazaadenine, N⁴,N⁴-ethanocytosin, N⁶,N⁶-ethano-2,6-diaminopurine, 5-halouracil (e.g., 5-fluorouracil and 5-bromouracil), pseudoisocytosine, isocytosine, isoguanine, and other heterocyclic bases described in U.S. Pat. Nos. 5,432,272 and 7,125,855, which are incorporated herein by reference for the limited purpose of disclosing additional heterocyclic bases. In some embodiments, a heterocyclic base can be optionally substituted with an amine or an enol protecting group(s).

[0077] The term “—N-linked amino acid” refers to an amino acid that is attached to the indicated moiety via a main-chain amino or mono-substituted amino group. When the amino acid is attached in an —N-linked amino acid, one of the hydrogens that is part of the main-chain amino or mono-substituted amino group is not present and the amino acid is attached via the nitrogen. As used herein, the term “amino acid” refers to any amino acid (both standard and non-standard amino acids), including, but not limited to, α-amino acids, β-amino acids, γ-amino acids and 8-amino acids. Examples of suitable amino acids include, but are not limited to, alanine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine, proline, serine, tyrosine, arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Additional examples of suitable amino acids include, but are not limited to, ornithine, hypusine, 2-aminoisobutyric acid, dehydroalanine, gamma-aminobutyric acid, citrulline, beta-alanine, alpha-ethyl-glycine, alpha-propyl-glycine and norleucine. N-linked amino acids can be substituted or unsubstituted.

[0078] The term “—N-linked amino acid ester derivative” refers to an amino acid in which a main-chain carboxylic acid group has been converted to an ester group. In some embodiments, the ester group has a formula selected from alkyl-O—C(═O)—, cycloalkyl-O—C(═O)—, aryl-O—C(═O)— and aryl(alkyl)-O—C(═O)—. A non-limiting list of ester groups include substituted and unsubstituted versions of the following: methyl-O—C(═O)—, ethyl-O—C(═O)—, n-propyl-O—C(═O)—, isopropyl-O—C(═O)—, n-butyl-O—C(═O)—, isobutyl-O—C(═O)—, tert-butyl-O—C(═O)—, neopentyl-O—C(═O)—, cyclopropyl-O—C(═O)—, cyclobutyl-O—C(═O)—, cyclopentyl-O—C(═O)—, cyclohexyl-O—C(═O)—, benzyl-O—C(═O)—, and naphthyl-O—C(═O)—. N-linked amino acid ester derivatives can be substituted or unsubstituted.

[0079] The terms “protecting group” and “protecting groups” as used herein refer to any atom or group of atoms that is added to a molecule in order to prevent existing groups in the molecule from undergoing unwanted chemical reactions. Examples of protecting group moieties are described in T. W. Greene and P. G. M. Wuts, Protective Groups in Organic Synthesis, 3. Ed. John Wiley & Sons, 1999, and in J. F. W. McOmie, Protective Groups in Organic Chemistry Plenum Press, 1973, both of which are hereby incorporated by reference for the limited purpose of disclosing suitable protecting groups. The protecting group moiety may be chosen in such a way, that they are stable to certain reaction conditions and readily removed at a convenient stage using methodology known from the art. A non-limiting list of protecting groups include benzyl; substituted benzyl; alkylcarbonyls and alkoxycarbonyls (e.g., t-butoxycarbonyl (BOC), acetyl, or isobutyryl); arylalkylcarbonyls and arylalkoxycarbonyls (e.g., benzyloxycarbonyl); substituted methyl ether (e.g., methoxymethyl ether); substituted ethyl ether; a substituted benzyl ether; tetrahydropyranyl ether; silyls (e.g., trimethylsilyl, triethylsilyl, triisopropylsilyl, t-butyldimethylsilyl, tri-iso-propylsilyloxymethyl, [2-(trimethylsilyl)ethoxy]methyl or t-butyldiphenylsilyl); esters (e.g., benzoate ester); carbonates (e.g., methoxymethylcarbonate); sulfonates (e.g., tosylate or mesylate); acyclic ketal (e.g., dimethyl acetal); cyclic ketals (e.g., 1,3-dioxane, 1,3-dioxolanes, and those described herein); acyclic acetal; cyclic acetal (e.g., those described herein); acyclic hemiacetal; cyclic hemiacetal; cyclic dithioketals (e.g., 1,3-dithiane or 1,3-dithiolane); orthoesters (e.g., those described herein) and triarylmethyl groups (e.g., trityl; monomethoxytrityl (MMTr); 4,4′-dimethoxytrityl (DMTr); 4,4′,4″-trimethoxytrityl (TMTr); and those described herein).

[0080] “Leaving group” as used herein refers to any atom or moiety that is capable of being displaced by another atom or moiety in a chemical reaction. More specifically, in some embodiments, “leaving group” refers to the atom or moiety that is displaced in a nucleophilic substitution reaction. In some embodiments, “leaving groups” are any atoms or moieties that are conjugate bases of strong acids. Examples of suitable leaving groups include, but are not limited to, tosylates and halogens. Non-limiting characteristics and examples of leaving groups can be found, for example in Organic Chemistry, 2d ed., Francis Carey (1992), pages 328-331; Introduction to Organic Chemistry, 2d ed., Andrew Streitwieser and Clayton Heathcock (1981), pages 169-171; and Organic Chemistry, 5^th ed., John McMurry (2000), pages 398 and 408; all of which are incorporated herein by reference for the limited purpose of disclosing characteristics and examples of leaving groups.

[0081] The term “pharmaceutically acceptable salt” refers to a salt of a compound that does not cause significant irritation to an organism to which it is administered and does not abrogate the biological activity and properties of the compound. In some embodiments, the salt is an acid addition salt of the compound. Pharmaceutical salts can be obtained by reacting a compound with inorganic acids such as a hydrohalic acid (e.g., hydrochloric acid or hydrobromic acid), sulfuric acid, nitric acid and phosphoric acid. Pharmaceutical salts can also be obtained by reacting a compound with an organic acid such as aliphatic or aromatic carboxylic or sulfonic acids, for example formic, acetic, succinic, lactic, malic, tartaric, citric, ascorbic, nicotinic, methanesulfonic, ethanesulfonic, p-toluensulfonic, salicylic or naphthalenesulfonic acid. Pharmaceutical salts can also be obtained by reacting a compound with a base to form a salt such as an ammonium salt, an alkali metal salt, such as a sodium or a potassium salt, an alkaline earth metal salt, such as a calcium or a magnesium salt, a salt of organic bases such as di cyclohexylamine, N-methyl-D-glucamine, tris(hydroxymethyl)methylamine, C₁-C₇ alkylamine, cyclohexylamine, triethanolamine, ethylenediamine, and salts with amino acids such as arginine and lysine.

[0082] Terms and phrases used in this application, and variations thereof, especially in the appended claims, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing, the term ‘including’ should be read to mean ‘including, without limitation,’ ‘including but not limited to,’ or the like; the term ‘comprising’ as used herein is synonymous with ‘including,’ ‘containing,’ or ‘characterized by,’ and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps; the term ‘having’ should be interpreted as ‘having at least;’ the term ‘includes’ should be interpreted as ‘includes but is not limited to;’ the term ‘example’ is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof; and use of terms like ‘preferably,’ preferred, ‘desired,’ or ‘desirable,’ and words of similar meaning should not be understood as implying that certain features are critical, essential, or even important to the structure or function of the invention, but instead as merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment. In addition, the term “comprising” is to be interpreted synonymously with the phrases “having at least” or “including at least”. When used in the context of a process, the term “comprising” means that the process includes at least the recited steps, but may include additional steps. When used in the context of a compound, composition or device, the term “comprising” means that the compound, composition or device includes at least the recited features or components, but may also include additional features or components. Likewise, a group of items linked with the conjunction ‘and’ should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as ‘and/or’ unless expressly stated otherwise. Similarly, a group of items linked with the conjunction ‘or’ should not be read as requiring mutual exclusivity among that group, but rather should be read as ‘and/or’ unless expressly stated otherwise.

[0083] With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity. The indefinite article “a” or “an” does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

[0084] It is understood that, in any compound described herein having one or more chiral centers, if an absolute stereochemistry is not expressly indicated, then each center may independently be of R-configuration or S-configuration or a mixture thereof. Thus, the compounds provided herein may be enantiomerically pure, enantiomerically enriched, racemic mixture, diastereomerically pure, diastereomerically enriched, or a stereoisomeric mixture. In addition it is understood that, in any compound described herein having one or more double bond(s) generating geometrical isomers that can be defined as E or Z, each double bond may independently be E or Z a mixture thereof.

[0085] Likewise, it is understood that, in any compound described, all tautomeric forms are also intended to be included. For example all tautomers of phosphate groups are intended to be included. Furthermore, all tautomers of heterocyclic bases known in the art are intended to be included, including tautomers of natural and non-natural purine-bases and pyrimidine-bases.

[0086] It is to be understood that where compounds disclosed herein have unfilled valencies, then the valencies are to be filled with hydrogens or isotopes thereof, e.g., hydrogen-1 (protium) and hydrogen-2 (deuterium).

[0087] It is understood that the compounds described herein can be labeled isotopically. Substitution with isotopes such as deuterium may afford certain therapeutic advantages resulting from greater metabolic stability, such as, for example, increased in vivo half-life or reduced dosage requirements. Each chemical element as represented in a compound structure may include any isotope of said element. For example, in a compound structure a hydrogen atom may be explicitly disclosed or understood to be present in the compound. At any position of the compound that a hydrogen atom may be present, the hydrogen atom can be any isotope of hydrogen, including but not limited to hydrogen-1 (protium) and hydrogen-2 (deuterium). Thus, reference herein to a compound encompasses all potential isotopic forms unless the context clearly dictates otherwise.

[0088] It is understood that the methods and combinations described herein include crystalline forms (also known as polymorphs, which include the different crystal packing arrangements of the same elemental composition of a compound), amorphous phases, salts, solvates, and hydrates. In some embodiments, the compounds described herein exist in solvated forms with pharmaceutically acceptable solvents such as water, ethanol, or the like. In other embodiments, the compounds described herein exist in unsolvated form. Solvates contain either stoichiometric or non-stoichiometric amounts of a solvent, and may be formed during the process of crystallization with pharmaceutically acceptable solvents such as water, ethanol, or the like. Hydrates are formed when the solvent is water, or alcoholates are formed when the solvent is alcohol. In addition, the compounds provided herein can exist in unsolvated as well as solvated forms. In general, the solvated forms are considered equivalent to the unsolvated forms for the purposes of the compounds and methods provided herein.

[0089] Where a range of values is provided, it is understood that the upper and lower limit, and each intervening value between the upper and lower limit of the range is encompassed within the embodiments.

[0090] Some embodiments disclosed herein relate to a compound of Formula (I) or a pharmaceutically acceptable salt thereof:

wherein: B¹ can be an optionally substituted heterocyclic base or an optionally substituted heterocyclic base with a protected amino group; X¹ can be O (oxygen) or S (sulfur); R¹ can be selected from —Z¹—R⁹, an optionally substituted N-linked amino acid and an optionally substituted N-linked amino acid ester derivative; Z¹ can be selected from O (oxygen), S (sulfur) and N(R¹⁰); R² and R³ can be independently selected from hydrogen, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl, an optionally substituted C_1-6 haloalkyl and an optionally substituted aryl(C_1-6 alkyl); or R² and R³ can be taken together to form a group selected from an optionally substituted C_3-6 cycloalkyl, an optionally substituted C_3-6 cycloalkenyl, an optionally substituted C_3-6 aryl and an optionally substituted C_3-6 heteroaryl; R⁴ can be selected from hydrogen, halogen, azido, cyano, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl and an optionally substituted allenyl; R⁵ can be hydrogen or an optionally substituted C₁-6 alkyl; R⁶ can be selected from hydrogen, halogen, azido, amino, cyano, an optionally substituted C_1-6 alkyl, —OR¹¹ and —OC(═O)R¹²; R⁷ can be selected from hydrogen, halogen, azido, cyano, an optionally substituted C_1-6 alkyl, —OR¹³ and —OC(═O)R¹⁴; R⁸ can be selected from hydrogen, halogen, azido, cyano, an optionally substituted C_1-6 alkyl, —OR¹⁵ and —OC(═O)R¹⁶; R⁹ can be selected from an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted heterocyclyl, an optionally substituted aryl(C_1-6 alkyl), an optionally substituted heteroaryl(C_1-6 alkyl), an optionally substituted heterocyclyl(C_1-6 alkyl), and Formula (II); R¹⁰ can be selected from hydrogen, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted heterocyclyl, an optionally substituted aryl(C_1-6 alkyl), an optionally substituted heteroaryl(C_1-6 alkyl) and an optionally substituted heterocyclyl(C_1-6 alkyl); R¹¹, R¹³ and R¹⁵ can be independently hydrogen or an optionally substituted C_1-6 alkyl; R¹², R¹⁴ and R¹⁶ can be independently an optionally substituted C_1-6 alkyl or an optionally substituted C_3-6 cycloalkyl; and Formula (II) can be:

wherein: R²⁰ and R²¹ can be independently selected from a hydrogen, an optionally substituted C_1-24 alkyl and an optionally substituted aryl; R²² can be selected from a hydrogen, an optionally substituted C_1-24 alkyl, an optionally substituted aryl, an optionally substituted —O—C_1-24 alkyl and an optionally substituted —O-aryl; and Y¹ can be O (oxygen) or S (sulfur).

[0091] In some embodiments, a compound of Formula (I) cannot have a structure selected from:

[0092] In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹, Z¹ is N(R¹⁰) and R¹⁰ is hydrogen, then R⁹ cannot be an optionally substituted phenyl. In some embodiments, when X¹ is S (sulfur), Z¹ is N(R¹⁰) and R¹⁰ is hydrogen, then R⁹ cannot be an unsubstituted aryl, for example an unsubstituted phenyl. In other embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is N(R¹⁰), then R⁹ and R¹⁰ cannot both be methyl or ethyl. In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is N(R¹⁰), then R⁹ and R¹⁰ cannot both be an unsubstituted C_1-4 alkyl. In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is N(R¹⁰), then R⁹ and R¹⁰ cannot both be an optionally substituted C_1-4 alkyl. In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is N(R¹⁰), then R⁹ and R¹⁰ cannot both be an unsubstituted alkyl. In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is N(R¹⁰), then R⁹ and R¹⁰ cannot both be an optionally substituted alkyl.

[0093] In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be methyl. In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an unsubstituted alkyl, for example an unsubstituted C_1-4 alkyl. In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an optionally substituted alkyl, for example an optionally substituted C_1-4 alkyl. In other embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be —CH₂—OC(═O)—(C_1-4 alkyl), such as —CH₂—OC(═O)CH₃ or —CH₂—OC(═O)C(CH₃). In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be —CH₂—OC(═O)—O—(C_1-6 alkyl), such as —CH₂—OC(═O)—O— isopropyl. In still other embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be —CH₂CH═CH₂. In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an unsubstituted C_1-4 alkenyl. In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an unsubstituted alkenyl. In other embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be 2-chlorophenyl. In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an optionally substituted aryl, such as an unsubstituted or substituted phenyl.

[0094] In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹, Z¹ is N(R¹⁰) and R¹⁰ is hydrogen, then R⁹ cannot be an optionally substituted phenyl. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹, Z¹ is N(R¹⁰) and R¹⁰ is hydrogen, then R⁹ cannot be an optionally substituted aryl, such as an unsubstituted or substituted phenyl. In other embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹, Z¹ is N(R¹⁰) and R¹⁰ is hydrogen, then R⁹ cannot be an optionally substituted benzyl. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹, Z¹ is N(R¹⁰) and R¹⁰ is hydrogen, then R⁹ cannot be an unsubstituted aryl(C_1-6 alkyl). In still other embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹, Z¹ is N(R¹⁰) and R¹⁰ is hydrogen, then R⁹ cannot be a substituted aryl(C_1-6 alkyl). In yet still other embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is N(R¹⁰), then R⁹ and R¹⁰ cannot be an unsubstituted C_1-4 alkyl. Examples of C_1-4 alkyls are described herein. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is N(R¹⁰), then R⁹ and R¹⁰ cannot both be an optionally substituted alkyl, such as an optionally substituted C_1-4 alkyl.

[0095] In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be methyl. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an unsubstituted C_1-4 alkyl. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an optionally substituted alkyl, such as an optionally substituted C_1-4 alkyl. In other embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be —CH₂—OC(═O)—(C_1-4 alkyl), such as —CH₂—OC(═O)CH₃, or —CH₂—OC(═O)C(CH₃). In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be —CH₂—OC(═O)—O—(C_1-6 alkyl), such as —CH₂—OC(═O)—O-isopropyl. In still other embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an optionally substituted phenyl. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an unsubstituted aryl. In yet still other embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is O (oxygen), then R⁹ cannot be an optionally substituted aryl(C_1-6 alkyl), for example, an optionally substituted benzyl.

[0096] In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is S (sulfur), then R⁹ cannot be methyl. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is S (sulfur), then R⁹ cannot be an unsubstituted C_1-4 alkyl. Examples of C_1-4 alkyl groups are described herein. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is S (sulfur), then R⁹ cannot be an optionally substituted alkyl. In other embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is S (sulfur), then R⁹ cannot be —CH₂—C(═O)—C(═O)—CH₂-halo, such as —CH₂—C(═O)—C(═O)—CH₂Br, —CH₂—C(═O)—C(═O)—CH₂Cl, —CH₂—C(═O)—C(═O)—CH₂F, or —CH₂—C(═O)—C(═O)—CH₂I. In other embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is S (sulfur), then R⁹ cannot be —CH₂—OC(═O)-t-butyl, —CH₂—OC(═O)-methyl, —CH₂—OC(═O)(C_1-6 alkyl), —CH₂—OC(═O)—O-isopropyl, or —CH₂—OC(═O)—O—(C_1-6 alkyl). In still other embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is S (sulfur), then R⁹ cannot be 4-nitro-benzyl or 4-isobutyryloxy-benzyl. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is S (sulfur), then R⁹ cannot be an optionally substituted aryl(C_1-6 alkyl).

[0097] The compound of Formula (I) can have various phosphorous containing groups. For example, the cyclic phosphorous containing group can be a cyclic phosphate, a cyclic phosphorothioate, a cyclic phosphoramidate or a cyclic thiophosphoramidate. In some embodiments, X¹ can be O (oxygen). In some embodiments, X¹ can be O (oxygen), and R¹ can be —Z¹—R⁹. In some embodiments, X¹ can be O (oxygen), R¹ can be —Z¹—R⁹, and Z¹ can be O (oxygen). In other embodiments, X¹ can be O (oxygen), R¹ can be —Z¹—R⁹, and Z¹ can be S (sulfur). In other embodiments, X¹ can be O (oxygen), R¹ can be —Z¹—R⁹, and Z¹ can be) N(R¹⁰).

[0098] In some embodiments, X¹ can be S (sulfur). In some embodiments, X¹ can be S (sulfur), and R¹ can be —Z¹—R⁹. In some embodiments, X¹ can be S (sulfur), R¹ can be —Z¹—R⁹, and Z¹ can be O (oxygen). In other embodiments, X¹ can be S (sulfur), R¹ can be —Z¹—R⁹, and Z¹ can be S (sulfur). In other embodiments, X¹ can be S (sulfur), R¹ can be —Z¹—R⁹, and Z¹ can be N(R¹⁰).

[0099] The substituents attached to the 5′-position of a compound of Formula (I) can vary. In some embodiments, R² and R³ can be the same. In other embodiments, R² and R³ can be different. In some embodiments, at least one of R² and R³ can be hydrogen. In other embodiments, both R² and R³ can be hydrogen. In some embodiments, at least one of R² and R³ can be selected from of an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl, an optionally substituted C_1-6 haloalkyl and an optionally substituted aryl(C_1-6 alkyl), or R² and R³ can be taken together to form a group selected from an optionally substituted C_3-6 cycloalkyl, an optionally substituted C_3-6 cycloalkenyl, an optionally substituted C_3-6 aryl and an optionally substituted C_3-6 heteroaryl. In some embodiments, at least one of R² and R³ cannot be hydrogen. In some embodiments, at least one of R² and R³ can be an optionally substituted C_1-6-alkyl; and the other of R² and R³ can be hydrogen. Examples of suitable optionally substituted C_1-6 alkyls include optionally substituted variants of the following: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl (branched and straight-chained), and hexyl (branched and straight-chained). In some embodiments, at least one of R² and R³ can be methyl, and the other of R² and R³ can be hydrogen. In other embodiments, at least one of R² and R³ can be an optionally substituted C_1-6-haloalkyl, and the other of R² and R³ can be hydrogen. One example of a suitable optionally substituted C_1-6-haloalkyl is CF₃. In some embodiments, when X¹ is O (oxygen), and R¹ is —O—R⁹ or —N(R¹⁰)—R⁹, then at least one of R² and R³ can be selected from an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl, an optionally substituted C_1-6 haloalkyl and an optionally substituted aryl(C_1-6 alkyl), or R² and R³ can be taken together to form a group selected from an optionally substituted C_3-6 cycloalkyl, an optionally substituted C_3-6 cycloalkenyl, an optionally substituted C_3-6 aryl and an optionally substituted C_3-6 heteroaryl. In some embodiments, when X¹ is O (oxygen), and R¹ is —O—R⁹ or —N(R¹⁹)—R⁹, then at least one of R² and R³ cannot be hydrogen. In some embodiments, R³, R⁴, R⁵ and R⁸ can each be hydrogen; and R² can be an optionally substituted C_1-6 alkyl. Suitable C_1-6 alkyl groups are described herein. When the substituents attached to the 5′-carbon make the 5′-carbon chiral, in some embodiments, the 5′-carbon can be a (R)-stereocenter. In other embodiments, the 5′-carbon can be an (S)-stereocenter.

[0100] Various amino acids derivatives can be used, including those described herein. In some embodiments, R¹ can be an optionally substituted N-linked α-amino acid. Suitable amino acids include, but are not limited to, alanine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine, proline, serine, tyrosine, arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Additional suitable amino acids include, but are not limited to, alpha-ethyl-glycine, alpha-propyl-glycine and beta-alanine. In other embodiments, R¹ can be an optionally substituted N-linked α-amino acid ester derivative. Various amino acid ester derivatives can be used, including those described herein. For example, R¹ can be an ester derivative of any of the following amino acids: alanine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine, proline, serine, tyrosine, arginine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Additional examples of N-linked amino acid ester derivatives include, but are not limited to, an ester derivative of any of the following amino acids: alpha-ethyl-glycine, alpha-propyl-glycine and beta-alanine.

[0101] In some embodiments, R¹ can be an ester derivative of alanine. In some embodiments, R¹ can be selected from alanine methyl ester, alanine ethyl ester, alanine isopropyl ester, alanine cyclohexyl ester, alanine neopentyl ester, valine isopropyl ester and leucine isopropyl ester. In some embodiments, the optionally substituted N-linked amino acid or the optionally substituted N-linked amino acid ester derivative can be in the L-configuration. In other embodiments, the optionally substituted N-linked amino acid or the optionally substituted N-linked amino acid ester derivative can be in the D-configuration.

[0102] In some embodiments, R¹ can have the structure

wherein R¹⁷ can be selected from hydrogen, an optionally substituted C_1-6-alkyl, an optionally substituted C_3-6 cycloalkyl, an optionally substituted aryl, an optionally substituted aryl(C_1-6 alkyl) and an optionally substituted C_1-6, haloalkyl; R¹⁸ can be selected from hydrogen, an optionally substituted C_1-6 alkyl, an optionally substituted C_1-6 haloalkyl, an optionally substituted C_3-6 cycloalkyl, an optionally substituted C₆ aryl, an optionally substituted C₁₀ aryl and an optionally substituted aryl(C_1-6 alkyl); and R¹⁹ can be hydrogen or an optionally substituted C_1-4-alkyl; or R¹⁸ and R¹⁹ can be taken together to form an optionally substituted C_3-6 cycloalkyl.

[0103] When R¹ has the structure

R¹⁸ can be an optionally substituted C_1-6-alkyl. Examples of suitable optionally substituted C_1-6-alkyls include optionally substituted variants of the following: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl (branched and straight-chained), and hexyl (branched and straight-chained). When R¹⁸ is substituted, R¹⁸ can be substituted with one or more substituents selected from N-amido, mercapto, alkylthio, an optionally substituted aryl, hydroxy, an optionally substituted heteroaryl, O-carboxy, and amino. In some embodiments, R¹⁸ can be an unsubstituted C_1-6-alkyl, such as those described herein. In some embodiments, R¹⁸ can be methyl.

[0104] As to R¹⁷, in some embodiments, R¹⁷ can be an optionally substituted C_1-6 alkyl. Examples of optionally substituted C_1-6-alkyls include optionally substituted variants of the following: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl (branched and straight-chained), and hexyl (branched and straight-chained). In some embodiments, R¹⁷ can be methyl or isopropyl. In some embodiments, R¹⁷ can be ethyl or neopentyl. In other embodiments, R¹⁷ can be an optionally substituted C_3-6 cycloalkyl. Examples of optionally substituted C_3-6 cycloalkyl include optionally substituted variants of the following: cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. In some embodiments, R¹⁷ can be an optionally substituted cyclohexyl. In still other embodiments, R¹⁷ can be an optionally substituted aryl, such as phenyl and naphthyl. In yet still other embodiments, R¹⁷ can be an optionally substituted aryl(C_1-6 alkyl). In some embodiments, R¹⁷ can be an optionally substituted benzyl. In some embodiments, R¹⁷ can be an optionally substituted C_1-6 haloalkyl, for example, CF₃.

[0105] In some embodiments, R¹⁹ can be hydrogen. In other embodiments, R¹⁹ can be an optionally substituted C_1-4-alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. In some embodiments, R¹⁹ can be methyl. In some embodiments, R¹⁸ can be hydrogen. In some embodiments, R¹⁸ and R¹⁹ can be taken together to form an optionally substituted C_3-6 cycloalkyl. Examples of optionally substituted C_3-6 cycloalkyl include optionally substituted variants of the following: cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Depending on the groups that are selected for R¹⁸ and R¹⁹, the carbon to which R¹⁸ and R¹⁹ are attached may be a chiral center. In some embodiments, the carbon to which R¹⁸ and R¹⁹ are attached may be a (R)-chiral center. In other embodiments, the carbon to which R¹⁸ and R¹⁹ are attached may be a (S)-chiral center.

[0106] As example of a suitable

groups include the following:

[0107] In some embodiments, R⁴ can be halogen, azido, cyano, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl or an optionally substituted allenyl. In some embodiments, R⁴ can be hydrogen. In other embodiments, R⁴ can be azido. In other embodiments, R⁴ can be cyano. In still other embodiments, R⁴ can be an optionally substituted allenyl. In yet still other embodiments, R⁴ can be a halogen. In some embodiments, R⁴ can be fluoro. In other embodiments, R⁴ can be optionally substituted C_1-6 alkyl, such as those described herein. In still other embodiments, R⁴ can be optionally substituted C_2-6 alkenyl. In yet still other embodiments, R⁴ can be optionally substituted C_2-6 alkynyl.

[0108] Various substituents can be attached to the 3′-carbon. In some embodiments, R⁵ can be hydrogen. In other embodiments, R⁵ can be an optionally substituted C_1-6 alkyl. Examples of optionally substituted C_1-6-alkyls include optionally substituted variants of the following: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl (branched and straight-chained), and hexyl (branched and straight-chained).

[0109] The substituents attached to the 2′-carbon can vary. In some embodiments, R⁶ can be hydrogen. In some embodiments, R⁶ can be halogen, azido, amino, cyano, an optionally substituted C_1-6 alkyl, —OR¹¹ or —OC(═O)R¹². In some embodiments, R⁶ can be halogen. In other embodiments, R⁶ can be azido. In still other embodiments, R⁶ can be amino. In yet still other embodiments, R⁶ can be cyano. In some embodiments, R⁶ can be an optionally substituted C_1-6 alkyl. Examples of optionally substituted C_1-6 alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. In other embodiments, R⁶ can be —OR¹¹. In some embodiments, when R¹¹ is hydrogen, R⁶ can be a hydroxy group. In other embodiments, when R¹¹ is an optionally substituted C_1-6 alkyl, R⁶ can be an optionally substituted C_1-6 alkoxy. Suitable optionally substituted C_1-6 alkoxy groups are described herein. In some embodiments, R⁶ can be —OC(═O)R¹², wherein R¹² can be an optionally substituted C_1-6 alkyl, such as optionally substituted variants of the following: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl (branched and straight-chained), and hexyl (branched and straight-chained). In other embodiments, R⁶ can be —OC(═O)R¹², wherein R¹² can be an optionally substituted C_3-6 cycloalkyl.

[0110] In some embodiments, R⁷ can be hydrogen. In some embodiments, R⁷ can be halogen, azido, cyano, an optionally substituted C_1-6 alkyl, —OR¹³ or —OC(═O)R¹⁴. In some embodiments, R⁷ can be halogen. In other embodiments, R⁷ can be azido. In still other embodiments, R⁷ can be cyano. In other embodiments, R⁷ can be an optionally substituted C_1-6 alkyl. Examples of optionally substituted C_1-6 alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. In still other embodiments, R⁷ can be —OR¹³. When R¹³ is hydrogen, R⁷ can be hydroxy. Alternatively, when R¹³ is an optionally substituted C_1-6 alkyl, R⁷ can be an optionally substituted C_1-6 alkoxy. Suitable alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, tert-butoxy, pentoxy (branched and straight-chained), and hexoxy (branched and straight-chained). In some embodiments, R⁷ can be —OC(═O)R¹⁴ in which R¹⁴ is an optionally substituted C_1-6 alkyl or an optionally substituted C_3-6 cycloalkyl. Examples of suitable C_1-6 alkyl groups are described herein.

[0111] In some embodiments, at least one of R⁶ and R⁷ can be a halogen. In some embodiments, R⁶ and R⁷ can both be a halogen. In other embodiments, R⁶ can be a halogen and R⁷ can be an optionally substituted C_1-6 alkyl, such as those described herein. In still other embodiments, R⁶ can be a hydroxy and R⁷ can be an optionally substituted C_1-6 alkyl, such as those described herein.

[0112] In some embodiments, R⁸ can be hydrogen. In some embodiments, R⁸ can be halogen, azido, cyano, an optionally substituted C_1-6 alkyl, —OR¹⁵ or —OC(═O)R¹⁶. In some embodiments, R⁸ can be halogen. In other embodiments, R⁸ can be azido. In still other embodiments, R⁸ can be cyano. In other embodiments, R⁸ can be an optionally substituted C_1-6 alkyl. Examples of optionally substituted C_1-6 alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. In still other embodiments, R⁸ can be —OR¹⁵. When R¹⁵ is hydrogen, R⁸ can be hydroxy. Alternatively, when R¹⁵ is an optionally substituted C_1-6 alkyl, R⁸ can be an optionally substituted C_1-6 alkoxy. Suitable alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, tert-butoxy, pentoxy (branched and straight-chained), and hexoxy (branched and straight-chained). In some embodiments, R⁸ can be —OC(═O)R¹⁶ in which R¹⁶ is an optionally substituted C_1-6 alkyl or an optionally substituted C_3-6 cycloalkyl. Examples of suitable C_1-6 alkyl groups are described herein.

[0113] Those skilled in the art understand that when a hydrogen atom is removed or is absent from an oxygen atom, the oxygen atom can have a negative charge. For example, when R⁶ is a hydroxy group and the hydrogen is removed or absent, the oxygen atom to which to hydrogen atom was associated with can be Likewise, when R⁷ or R⁸ is a hydroxy group and the hydrogen is removed or is absent, the oxygen atom to which to hydrogen atom was associated with can be O⁻. In some embodiments, R², R³, R⁴, R⁵ and R⁸ can each be hydrogen.

[0114] When R¹ is Z¹—R⁹, the R⁹ group can vary. In some embodiments, R⁹ can be selected from an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted heterocyclyl, an optionally substituted aryl(C_1-6 alkyl), an optionally substituted heteroaryl(C_1-6 alkyl), an optionally substituted heterocyclyl(C_1-6 alkyl) and Formula (II). In other embodiments, R⁹ can be selected from an optionally substituted alkynyl, an optionally substituted cycloalkyl, an optionally substituted cycloalkenyl, an optionally substituted heteroaryl, an optionally substituted heterocyclyl, an optionally substituted heteroaryl(C_1-6 alkyl) and an optionally substituted heterocyclyl(C_1-6 alkyl). In some embodiments, R⁹ can be an optionally substituted alkyl. In some embodiments, R⁹ can be an optionally substituted C_1-6 alkyl. Examples of optionally substituted C_1-6 alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl. In some embodiments, R⁹ can be an optionally substituted aryl. In some embodiments, R⁹ can be an optionally substituted phenyl. In some embodiments, R⁹ can be an optionally substituted aryl(C_1-6 alkyl). In some embodiments, R⁹ can be benzyl. In some embodiments, R⁹ can be an optionally substituted cycloalkyl. In some embodiments, R⁹ can be cyclobutyl, cyclopentyl, or cyclohexyl. In some embodiments, R⁹ can be —CH₂-cyclopropyl. In some embodiments, R¹⁰ can be hydrogen or an optionally substituted alkyl (for example, an optionally substituted C_1-6 alkyl).

[0115] In some embodiments, R⁹ can be Formula (II). In some embodiments, R²⁰ and R²¹ both can be hydrogen. In some embodiments, R²⁰ and R²¹ can each be an optionally substituted C_1-24 alkyl or an optionally substituted aryl. In some embodiments, at least one of R²⁰ and R²¹ can an optionally substituted C_1-24 alkyl or an optionally substituted aryl, and the other of R²⁰ and R²¹ can be hydrogen. In some embodiments, R²² can be hydrogen. In some embodiments, R²² can be an optionally substituted C_1-24 alkyl. In some embodiments, R²² can be an optionally substituted aryl. In some embodiments, R²² can be an optionally substituted —O—C_1-24 alkyl. In some embodiments, R²² can be an optionally substituted —O—C_1-6 alkyl. Examples of optionally substituted C_1-6 alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, pentyl (branched and straight-chained), and hexyl (branched and straight-chained). In some embodiments, R²² can be an optionally substituted —O-aryl. In some embodiments, Y¹ can be O (oxygen). In some embodiments, Y¹ can be S (sulfur). In some embodiments, R⁹ can be Formula (II), R²⁰ and R²¹ both can be hydrogen, R²² can be an optionally substituted C_1-24 alkyl, and Y¹ can be O (oxygen). In other embodiments, R⁹ can be Formula (II), R²⁰ and R²¹ both can be hydrogen, R²² can be an optionally substituted C_1-24 alkyl, and Y¹ can be S (sulfur). In some embodiments, R²⁰ and R²¹ both can be hydrogen, R²² can be tert-butyl, and Y¹ can be O (oxygen). In other embodiments, R²⁰ and R²¹ both can be hydrogen, R²² can be tert-butyl, and Y¹ can be S (sulfur). In some embodiments, R⁹ can be pivaloyloxymethyl. In some embodiments, R⁹ can be isopropyloxycarbonyloxymethyl.

[0116] In some embodiments, R⁵ and R⁸ can each be hydrogen; and R⁴ can be azido. In other embodiments, R⁴, R⁵, R⁷ and R⁸ can each be hydrogen; and R⁶ can be —OH. In still other embodiments, R⁴, R⁵ and R⁸ can each be hydrogen; and R⁶ can be halogen. In yet still other embodiments, R⁴, R⁵ and R⁸ can each be hydrogen; and R⁷ can be an optionally substituted C_1-6 alkyl. In some embodiments, R⁴, R⁵ and R⁸ can each be hydrogen; R⁶ can be a halogen; and R⁷ can be an optionally substituted C_1-6 alkyl. In other embodiments, R⁴, R⁵ and R⁸ can each be hydrogen; and R⁷ can be methyl. In still other embodiments, R⁴, R⁵ and R⁸ can each be hydrogen; and R⁷ can be halogen. In some embodiments, R⁴, R⁵ and R⁸ can each be hydrogen; R⁶ can be a halogen; and R⁷ can be a halogen. In yet still other embodiments, R⁴, R⁵ and R⁸ can each be hydrogen; R⁶ can be —OR¹¹; R¹¹ can be hydrogen; and R⁷ can be an optionally substituted C_1-6 alkyl. In some embodiments, R⁴, R⁵ and R⁸ can each be hydrogen; R⁶ can be —OH; and R⁷ can be methyl. In other embodiments, R⁴, R⁵ and R⁸ can each be hydrogen; R⁶ can be —OR¹¹; R¹¹ can be hydrogen; and R⁷ can be halogen. In some of the embodiments of this paragraph, R² and R³ can both be hydrogen. In some of the embodiments of this paragraph, at least one of R² and R³ can be an optionally substituted C_1-6 alkyl; and the other of R² and R³ can be hydrogen.

[0117] Various optionally substituted heterocyclic bases can be attached to the pentose ring. In some embodiments, one or more of the amine and/or amino groups may be protected with a suitable protecting group. For example, an amino group may be protected by transforming the amine and/or amino group to an amide or a carbamate. In some embodiments, B¹ can be an optionally substituted heterocyclic base or an optionally substituted heterocyclic base with one or more protected amino groups can have one of the following structures:

wherein: R^A2 can be selected from hydrogen, halogen and NHR^J2, wherein R^J2 can be selected from hydrogen, —C(═O)R^K2 and —C(═O)OR^L2; R^B2 can be halogen or NHR^W2, wherein R^W2 is selected from hydrogen, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_3-8 cycloalkyl, —C(═O)R^m2 and —C(═O)OR^N2; R^C2 can be hydrogen or NHR^O2, wherein R^O2 can be selected from hydrogen, —C(═O)R^P2 and —C(═O)OR^Q2; R^D2 can be selected from hydrogen, halogen, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl and an optionally substituted C_2-6 alkynyl; R^E2 can be selected from hydrogen, an optionally substituted C_1-6 alkyl, an optionally substituted C_3-5 cycloalkyl, —C(═O)R^R2 and —C(═O)OR^S2; R^F2 can be selected from hydrogen, halogen, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl and an optionally substituted C_2-6 alkynyl; Y² can be N (nitrogen) or CR¹², wherein R¹² can be selected from hydrogen, halogen, an optionally substituted C_1-6-alkyl, an optionally substituted C_2-6-alkenyl and an optionally substituted C_2-6-alkynyl; R^G2 can be an optionally substituted C_1-6 alkyl; R^H2 can be hydrogen or NHR^T2, wherein R^T2 can be independently selected from hydrogen, —C(═O)R^U2 and —C(—O)OR^V2, and R^K2, R^L2, R^M2, R^N2, R^P2, R^Q2 R^R2, R^S2, R^U2 and R^V2 can be independently selected from C_1-6 alkyl, C_2-6 alkenyl, C_2-6 alkynyl, C_3-6 cycloalkyl, C_3-6 cycloalkenyl, C_3-6 cycloalkynyl, C_6-10 aryl, heteroaryl, heterocyclyl, aryl(C_1-6 alkyl), heteroaryl(C_1-6 alkyl) and heterocyclyl(C_1-6 alkyl). In some embodiments, the structures shown above can be modified by replacing one or more hydrogens with substituents selected from the list of substituents provided for the definition of “substituted.”

[0118] In some embodiments, B¹ can be selected from adenine, guanine, thymine, cytosine and uracil. In some embodiments, B¹ can be an optionally substituted

such as

In still other embodiments, B¹ can be

[0119] In yet still other embodiments, B¹ can be an optionally substituted

In some embodiments R^F2 can be hydrogen. In some embodiments, B¹ can be

In some embodiments, B¹ can be an optionally substituted

In some embodiments R^E2 is hydrogen. In some embodiments, B¹ can be

[0120] In other embodiments, B¹ can be

In yet still other embodiments, B¹ can be

In some embodiments, B¹ can be an optionally substituted

For example, B¹ can be

wherein R^G2 can be an optionally substituted C_1-4 alkyl; and R^H2 can be NH₂. In some embodiments, R^G2 can be methyl or ethyl.

[0121] In some embodiments, when X¹ is S (sulfur), R¹ is —Z¹—R⁹ and Z¹ is N(R¹⁰), then B¹ can be an optionally substituted cytosine or an optionally substituted uracil. In some embodiments, when X¹ is O (oxygen), R¹ is —Z¹—R⁹ and Z¹ is S (sulfur), then B¹ can be an optionally substituted cytosine.

[0122] In some embodiments, if B¹ is an optionally substituted guanine, then R¹ can be an optionally substituted N-linked amino acid or an optionally substituted N-linked amino acid ester derivative. In other embodiments, if B¹ is an optionally substituted guanine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted alkyl, such as a substituted C_1-6 alkyl. In still other embodiments, if B¹ is an optionally substituted guanine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted alkenyl. In yet still other embodiments, if B¹ is an optionally substituted guanine and R¹ is —Z¹—R⁹, then R⁹ can be an unsubstituted aryl. In some embodiments, if B¹ is an optionally substituted guanine and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II). In some embodiments, if B¹ is an optionally substituted guanine and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II), wherein R²⁰ and R²¹ both can be hydrogen, R²² can be an optionally substituted C_1-24 alkyl, and Y¹ can be O (oxygen) or S (sulfur). In some embodiments, if B¹ is an optionally substituted guanine and R¹ is —Z¹—R⁹, then R⁹ can be pivaloyloxymethyl. In some embodiments, if B¹ is an optionally substituted guanine and R¹ is —Z¹—R⁹, then R⁹ can be isopropyloxycarbonyloxymethyl. In some of the embodiments of this paragraph, the optionally substituted guanine can be a protected guanine. In some of the embodiments of this paragraph, X¹ is S (sulfur). In some of the embodiments of this paragraph, X¹ is O (oxygen).

[0123] In some embodiments, if B¹ is an optionally substituted uracil, then R¹ can be an optionally substituted N-linked amino acid or an optionally substituted N-linked amino acid ester derivative. In other embodiments, if B¹ is an optionally substituted uracil and R¹ is —Z¹—R⁹, then R⁹ can be a substituted alkyl. In still embodiments, if B¹ is an optionally substituted uracil and R¹ is —Z¹—R⁹, then R⁹ can be an unsubstituted aryl. In some embodiments, if B¹ is an optionally substituted uracil and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II). In some embodiments, if B¹ is an optionally substituted uracil and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II), wherein R²⁰ and R²¹ both can be hydrogen, R²² can be an optionally substituted C_1-24 alkyl, and Y¹ can be O (oxygen) or S (sulfur). In some embodiments, if B¹ is an optionally substituted uracil and R¹ is —Z¹—R⁹, then R⁹ can be pivaloyloxymethyl. In some embodiments, if B¹ is an optionally substituted uracil and R¹ is —Z¹—R⁹, then R⁹ can be isopropyloxycarbonyloxymethyl. In some of the embodiments of this paragraph, the optionally substituted uracil can be a protected uracil. In some of the embodiments of this paragraph, X¹ is S (sulfur). In some of the embodiments of this paragraph, X¹ is O (oxygen).

[0124] In some embodiments, if B¹ is an optionally substituted thymine, then R¹ can be an optionally substituted N-linked amino acid or an optionally substituted N-linked amino acid ester derivative. In other embodiments, if B¹ is an optionally substituted thymine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted alkyl. In still other embodiments, if B¹ is an optionally substituted thymine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted alkenyl. In yet still other embodiments, if B¹ is an optionally substituted thymine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted aryl. In some embodiments, if B¹ is an optionally substituted thymine and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II). In some embodiments, if B¹ is an optionally substituted thymine and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II), wherein R²⁰ and R²¹ both can be hydrogen, R²² can be an optionally substituted C_1-24 alkyl, and Y¹ can be O (oxygen) or S (sulfur). In some embodiments, if B¹ is an optionally substituted thymine and R¹ is —Z¹—R⁹, then R⁹ can be pivaloyloxymethyl. In some embodiments, if B¹ is an optionally substituted thymine and R¹ is —Z¹—R⁹, then R⁹ can be isopropyloxycarbonyloxymethyl. In some of the embodiments of this paragraph, the optionally substituted thymine can be a protected thymine. In some of the embodiments of this paragraph, X¹ is S (sulfur). In some of the embodiments of this paragraph, X¹ is O (oxygen).

[0125] In some embodiments, if B¹ is an optionally substituted adenine, then R¹ can be an optionally substituted N-linked amino acid or an optionally substituted N-linked amino acid ester derivative. In other embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted alkyl. In still other embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted alkenyl. In some embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II). In some embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II), wherein R²⁰ and R²¹ both can be hydrogen, R²² can be an optionally substituted C_1-24 alkyl, and Y¹ can be O (oxygen) or S (sulfur). In some embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ can be pivaloyloxymethyl. In some embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ can be isopropyloxycarbonyloxymethyl. In some of the embodiments of this paragraph, the optionally substituted adenine can be a protected adenine. In some of the embodiments of this paragraph, X¹ is S (sulfur). In some of the embodiments of this paragraph, X¹ is O (oxygen).

[0126] In some embodiments, if B¹ is an optionally substituted cytosine, then R¹ can be an optionally substituted N-linked amino acid or an optionally substituted N-linked amino acid ester derivative. In other embodiments, if B¹ is an optionally substituted cytosine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted alkyl. In still other embodiments, if B¹ is an optionally substituted cytosine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted alkenyl. In yet still other embodiments, if B¹ is an optionally substituted cytosine and R¹ is —Z¹—R⁹, then R⁹ can be a substituted aryl. In some embodiments, if B¹ is an optionally substituted cytosine and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II). In some embodiments, if B¹ is an optionally substituted cytosine and R¹ is —Z¹—R⁹, then R⁹ can be Formula (II), wherein R²⁰ and R²¹ both can be hydrogen, R²² can be an optionally substituted C_1-24 alkyl, and Y¹ can be O (oxygen) or S (sulfur). In some embodiments, if B¹ is an optionally substituted cytosine and R¹ is —Z¹—R⁹, then R⁹ can be pivaloyloxymethyl. In some embodiments, if B¹ is an optionally substituted cytosine and R¹ is —Z¹—R⁹, then R⁹ can be isopropyloxycarbonyloxymethyl. In some of the embodiments of this paragraph, the optionally substituted cytosine can be a protected cytosine. In some of the embodiments of this paragraph, X¹ is S (sulfur). In some of the embodiments of this paragraph, X¹ is O (oxygen).

[0127] In some embodiments, R⁴ cannot be hydrogen. In some embodiments, R⁵ cannot be hydrogen. In some embodiments, R⁶ cannot be hydrogen. In some embodiments, R⁶ cannot be a hydroxy group. In other embodiments, when R⁶ is —OC(═O)R¹², then R¹² cannot be —CH—(CH₃)₂. In still other embodiments, when R⁶ is —OC(═O)R¹², then R¹² cannot be an optionally substituted alkyl, for example, a substituted C_1-4 alkyl or an unsubstituted C_1-4 alkyl. In some embodiments, R⁷ cannot be hydrogen. In some embodiments, R⁸ cannot be hydrogen. In some embodiments, R⁹ cannot be an optionally substituted alkyl, such as a substituted or unsubstituted C_1-4 alkyl. In other embodiments, R⁹ cannot be an optionally substituted alkenyl, for example —CH₂CH═CH₂. In still other embodiments, R⁹ cannot be an optionally substituted aryl, such as an optionally substituted phenyl. In yet still other embodiments, R⁹ cannot be an optionally substituted aryl(C_1-6 alkyl), such as an optionally substituted benzyl. In some embodiments, R⁹ cannot be —CH₂—OC(═O)CH₃, —CH₂—OC(═O)-t-butyl, —CH₂—OC(═O)(C_1-6 alkyl), —CH₂—OC(═O)—O-isopropyl, or —CH₂—OC(═O)—O—(C_1-6 alkyl). In some embodiments, B¹ cannot be an optionally substituted

such as

In some embodiments, B¹ cannot be an optionally substituted

In some embodiments, B¹ cannot be an optionally substituted

such as

In some embodiments, B¹ cannot be an optionally substituted

In some embodiments, B¹ cannot be a dimethylformamide protected guanine or a 2-(nitrophenyl)ethyl protected guanine. In other embodiments, B¹ cannot be an acyl protected guanine. In still other embodiments, B¹ cannot be a 2-(nitrophenyl)ethyl protected uracil. In some embodiments, B¹ cannot be a 2-(nitrophenyl)sulfonylethyl protected uracil. In yet still other embodiments, B¹ cannot be a benzoyl protected adenine. In some embodiments, B¹ cannot be an anisoyl protected cytosine. In some embodiments, if B¹ is an optionally substituted guanine and R¹ is —Z¹—R⁹, then R⁹ cannot be methyl, —CH₂CH═CH₂, 2-chlorophenyl or —CH₂—C(═O)—C(═O)—CH₂-halo, such as —CH₂—C(═O)—C(═O)—CH₂Br, —CH₂—C(═O)—C(═O)—CH₂Cl, —CH₂—C(═O)—C(═O)—CH₂F, or —CH₂—C(═O)—C(═O)—CH₂I. In some embodiments, if B¹ is an optionally substituted uracil and R¹ is —Z¹—R⁹, then R⁹ cannot be methyl or 2-chlorophenyl. In some embodiments, if B¹ is an optionally substituted thymine and R¹ is —Z¹—R⁹, then R⁹ cannot be methyl or —CH₂CH═CH₂. In other embodiments, if B¹ is an optionally substituted thymine and R¹ is —Z¹—R⁹, then R⁹ cannot be an optionally substituted phenyl. In yet still other embodiments, if is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ cannot be methyl or ethyl. In some embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ cannot be —CH₂CH═CH₂. In other embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ cannot be phenyl. In some embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ cannot be 2-chlorophenyl, 4-nitro-benzyl or 4-isobutyryloxy-benzyl. In other embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ cannot be —CH₂—C(═O)—C(═O)—CH₂-halo, such as —CH₂—C(═O)—C(═O)—CH₂Br, —C_1-12—C(═O)—C(═O)—CH₂Cl, —CH₂—C(═O)—C(═O)—CH₂F, or —CH₂—C(═O)—C(═O)—CH₂I. In other embodiments, if B¹ is an optionally substituted adenine and R¹ is —Z¹—R⁹, then R⁹ cannot be —CH₂—OC(═O)CH₃, —CH₂—OC(═O)C(CH₃)₃, —CH₂—OC(═O)(C_1-6 alkyl), —CH₂—OC(═O)—O-isopropyl, or —CH₂—C(═O)—O—(C_1-6 alkyl).

[0128] Depending upon the substituents attached to the phosphorus atom, the phosphorus atom can be a chiral center. In some embodiments, the phosphorus can be a (R)-stereocenter. In other embodiments, the phosphorus can be a (S)-stereocenter.

[0129] In some embodiments, a compound of Formula (I) can be a single diastereomer. In other embodiments, a compound of Formula (I) can be a mixture of diastereomers. In some embodiments, a compound of Formula (I) can be a 1:1 mixture of two diastereomers. In some embodiments, a compound of Formula (I) can be diasteriometrically enriched (for example, one diastereomer can be present at a concentration of >55%, ≧75%, ≧80%, ≧90%, ≧95%, ≧98%, or ≧99% as compared to the total concentration of the other diastereomers).

[0130] Some embodiments of R¹ of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, are provided in Table 1. Tables 2-3 provide the structures of the variables aa01-aa11 and es01-es14, respectively. For example, the first entry in Table 1 is “aa01,es01,” which corresponds to a compound of Formula (I), wherein R¹ is

TABLE 1
R1, Rα	R1, Rα	R1, Rα	R1, Rα	R1, Rα	R1, Rα
aa01, es01	aa02, es01	aa03, es01	aa04, es01	aa05, es01	aa06, es09
aa01, es02	aa02, es02	aa03, es02	aa04, es02	aa05, es02	aa06, es10
aa01, es03	aa02, es03	aa03, es03	aa04, es03	aa05, es03	aa06, es11
aa01, es04	aa02, es04	aa03, es04	aa04, es04	aa05, es04	aa06, es12
aa01, es05	aa02, es05	aa03, es05	aa04, es05	aa05, es05	aa07, es09
aa01, es06	aa02, es06	aa03, es06	aa04, es06	aa05, es06	aa07, es10
aa01, es07	aa02, es07	aa03, es07	aa04, es07	aa05, es07	aa07, es11
aa01, es08	aa02, es08	aa03, es08	aa04, es08	aa05, es08	aa07, es12
aa01, es09	aa02, es09	aa03, es09	aa04, es09	aa05, es09	aa08, es09
aa01, es10	aa02, es10	aa03, es10	aa04, es10	aa05, es10	aa08, es10
aa01, es11	aa02, es11	aa03, es11	aa04, es11	aa05, es11	aa08, es11
aa01, es12	aa02, es12	aa03, es12	aa04, es12	aa05, es12	aa08, es12
aa06, es01	aa07, es01	aa08, es01	aa09, es01	aa10, es01	aa09, es09
aa06, es02	aa07, es02	aa08, es02	aa09, es02	aa10, es02	aa09, es10
aa06, es03	aa07, es03	aa08, es03	aa09, es03	aa10, es03	aa09, es11
aa06, es04	aa07, es04	aa08, es04	aa09, es04	aa10, es04	aa09, es12
aa06, es05	aa07, es05	aa08, es05	aa09, es05	aa10, es05	aa10, es09
aa06, es06	aa07, es06	aa08, es06	aa09, es06	aa10, es06	aa10, es10
aa06, es07	aa07, es07	aa08, es07	aa09, es07	aa10, es07	aa10, es11
aa06, es08	aa07, es08	aa08, es08	aa09, es08	aa10, es08	aa10, es12

TABLE 2
	aa01
	aa02
	aa03
	aa04
	aa05
	aa06
	aa07
	aa08
	aa09
	aa10

TABLE 3
es01	Rα = methyl	es02	Rα = ethyl	es03	Rα = isopropyl
es04	Rα = propyl	es05	Rα =	es06	Rα =
			cyclohexyl		cyclopentyl
es07	Rα = cyclobutyl	es08	Rα =	es09	Rα = benzyl
			cyclopropyl
es11	Rα = neopentyl	es10	Rα = t-butyl	es12	Rα = hydrogen

[0131] Examples of compounds of Formula (I) include, but are not limited to the following:

[0132] Compounds of Formula (I), and those described herein may be prepared in various ways. General synthetic routes to the compound of Formula (I), and some examples of starting materials used to synthesize the compounds of Formula (I) are shown in Schemes 1 and 2, and described herein. The routes shown and described herein are illustrative only and are not intended, nor are they to be construed, to limit the scope of the claims in any manner whatsoever. Those skilled in the art will be able to recognize modifications of the disclosed syntheses and to devise alternate routes based on the disclosures herein; all such modifications and alternate routes are within the scope of the claims.

[0133] One method for forming a compound of Formula (I) is shown in Scheme 1. In Scheme 1, R^1A, R^2A, R^3A, R^4A, R^5A, R^6A, R^7A, R^8A, X^1A and B^1A can be the same as R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, X¹ and B¹ as described herein for Formula (I); and each LG can be a leaving group, such as a halogen or a sulfonate ester. As shown in Scheme 1, a nucleoside with a hydroxy group attached to the 3′-carbon and a hydroxy group attached to 5′-carbon can be reacted with a compound having the formula, R^1AP(═X^1A)(LG)₂, in the presence of a base, to produce a compound of Formula (I). Suitable bases are known to those skilled in the art. For example, the base can be an amine base, such as an alkylamine (including mono-, di- and tri-alkylamines (e.g., triethylamine)), optionally substituted pyridines (e.g., collidine) and optionally substituted imidazoles (e.g., N-methylimidazole)).

[0134] Another method for forming a compound of Formula (I) is shown in Scheme 2. In Scheme 2, RIA, R^2A, R^3A, R^4A, R^5A, R^6A, R^7A, R^8A, X^1A and B^1A can be the same as R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, X¹ and B¹ as described herein for Formula (I); and each LG can be a leaving group, such as a halogen or a sulfonate ester. As illustrated in Scheme 2, a compound having a hydroxy group attached to the 3′-carbon and a hydroxy group attached to the 5′-carbon can be reacted with a compound having the formula, R^1AP(LG)₂, in the presence of a base, to produce a phosphite compound. Suitable bases are known to those skilled in the art and described herein. The phosphorus can then be oxidized to phosphorus(V) using a suitable oxidizing agent, to produce a compound of Formula (I) where X¹ is O (oxygen). Alternatively, the phosphite compound can be reacted with a sulfurization reagent to produce a compound of Formula (I) where X¹ is S (sulfur). Suitable oxidizing and sulfurization agents are known to those skilled in the art. For example, the oxidation can be carried out using iodine as the oxidizing agent and water as the oxygen donor. Suitable sulfurization agents include, but are not limited to, elemental sulfur, Lawesson's reagent, cyclooctasulfur, 3H-1,2-Benzodithiole-3-one-1,1-dioxide (Beaucage's reagent), 3-((N,N-dimethylaminomethylidene)amino)-3H-1,2,4-dithiazole-5-thione (DDTT) and bis(3-triethoxysilyl)propyl-tetrasulfide (TEST).

[0135] Any —NH, NH₂ and/or keto groups present on B^1A, for example, when B^1A is an optionally substituted heterocyclic base, can be protected with one or more suitable protecting groups. Examples of suitable protecting groups include triarylmethyl groups, (2-nitrophenyl)ethyl groups, acyl groups, and dialkylformamidine groups. To reduce the formation of side products, one or more the groups attached to the pentose ring can be protected with one or more suitable protecting groups. As an example, if R^4A, R^5A, R^6A, R^7A and/or R^8A is/are hydroxy group(s), the hydroxy group(s) can be protected with suitable protecting groups, such as triarylmethyl and/or silyl groups. Examples of triarylmethyl groups include but are not limited to, trityl, monomethoxytrityl (MMTr), 4,4′-dimethoxytrityl (DMTr), 4,4′,4″-trimethoxytrityl (TMTr), 4,4′,4″-tris-(benzoyloxy)trityl (TBTr), 4,4′,4″-tris (4,5-dichlorophthalimido) trityl (CPTr), 4,4′,4″-tris (levulinyloxy)trityl (TLTr), p-anisyl-1-naphthylphenylmethyl, di-o-anisyl-1-naphthylmethyl, p-tolyldipheylmethyl, 3-(imidazolylmethyl)-4,4′-dimethoxytrityl, 9-phenylxanthen-9-yl (Pixyl), 9-(p-methoxyphenyl)xanthen-9-yl (Mox), 4-decyloxytrityl, 4-hexadecyloxytrityl, 4,4′-dioctadecyltrityl, 9-(4-octadecyloxyphenyl)xanthen-9-yl, 1,1′-bis-(4-methoxyphenyl)-1′-pyrenylmethyl, 4,4′,4″-tris-(tert-butylphenyl)methyl (TTTr) and 4,4′-di-3,5-hexadienoxytrityl. Examples of silyl groups include, but are not limited to, trimethylsilyl (TMS), tert-butyldimethylsilyl (TBDMS), triisopropylsilyl (TIPS), tert-butyldiphenylsilyl (TBDPS), tri-iso-propylsilyloxymethyl and [2-(trimethylsilyl)ethoxy]methyl. Alternatively, at least two of R^4A, R^5A, R^6A, R^7A and R^8A can be protected by a single achiral or chiral protecting group, for example, by forming an orthoester, a cyclic acetal or a cyclic ketal. Suitable orthoesters include methoxymethylene acetal, ethoxymethylene acetal, 2-oxacyclopentylidene orthoester, dimethoxymethylene orthoester, 1-methoxyethylidene orthoester, 1-ethoxyethylidene orthoester, methylidene orthoester, phthalide orthoester 1,2-dimethoxyethylidene orthoester, and alpha-methoxybenzylidene orthoester; suitable cyclic acetals include methylene acetal, ethylidene acetal, t-butylmethylidene acetal, 3-(benzyloxy)propyl acetal, benzylidene acetal, 3,4-dimethoxybenzylidene acetal and p-acetoxybenzylidene acetal; and suitable cyclic ketals include 1-t-butylethylidene ketal, 1-phenylethylidene ketal, isopropylidene ketal, cyclopentylidene ketal, cyclohexylidene ketal, cycloheptylidene ketal and 1-(4-methoxyphenyl)ethylidene ketal.

[0136] The chirality of the 5′-carbon of compounds of Formulae (A) and/or (I) can be inverted using methods known to the skilled in the art. For example, the oxygen attached to the 5′-carbon can be oxidized, for example to an aldehyde for a compound of Formula (A) or ketone for a compound of Formula (I), using a suitable oxidizing agent. The aldehyde and/or ketone can then be reduced using a suitable reducing agent. Examples of suitable reducing agents include, but are not limited to, NaH, LiH, NaBH₄, LiAlH₄ and CaH₂. Suitable oxidizing and reducing agents are known to those skilled in the art. Examples of suitable oxidizing agents and conditions are described herein.

[0137] In some embodiments, R⁶, R⁷ and/or R⁸ can be —OC(═O)R¹¹, —OC(═O)R¹³, and —OC(═O)R¹⁵, respectively. The —OC(═O)R¹¹, —OC(═O)R¹³, and —OC(═O)R¹⁵ groups can be formed at the 1′ and 2′-positions using various methods known to those skilled in the art. As an example, a compound of Formula (I), wherein R⁶ and R⁸ are both hydroxy groups, can be treated with an alkyl anhydride (e.g., acetic anhydride and propionic anhydride) or an alkyl acid chloride (e.g., acetochloride). If desired, a catalyst can be used to facilitate the reaction. An example of suitable catalyst is 4-dimethylaminopyridine (DMAP). Alternatively, the —OC(═O)R¹¹ and —OC(═O)R¹⁵ groups can be formed at the 1′ and 2′-positions by reacting an alkyl acid (e.g., acetic acid and propionic acid) in the presences of a carbodiimide or a coupling reagent. Examples of carbodiimides include, but are not limited to, N,N-dicyclohexylcarbodiimide (DCC), N,N′-diisopropylcarbodiimide (DIC) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC).

[0138] As described herein, B^1A can include a carbamate and/or an amide. Those skilled in the art know methods for forming a carbamate and/or an amide on B^1A. In some embodiments, the carbamate can be formed using 1,1′-carbonyldiimidazole and an alcohol.

[0139] During the synthesis of any of the compounds described herein, if desired, any hydroxy groups attached to the pentose ring, and any —NH, NH₂ and/or keto groups present on the B^1A can be protected with one or more suitable protecting groups. Suitable protecting groups are described herein. Those skilled in the art will appreciate that groups attached to the pentose ring and any —NH, NH₂ and/or keto groups present on the B^1A can be protected with various protecting groups, and any protecting groups present can be exchanged for other protecting groups. The selection and exchange of the protecting groups is within the skill of those of ordinary skill in the art. Any protecting group(s) can also be removed by methods known in the art, for example, with an acid (e.g., a mineral or an organic acid), a base or a fluoride source.

[0140] In some embodiments, neutralizing the charge on the phosphate group may facilitate the penetration of the cell membrane by a compound of Formula (I), or a pharmaceutically acceptable salt thereof, by making the compound more lipophilic compared to a nucleotide having a comparable structure with one or more charges present on the phosphate. Once absorbed and taken inside the cell, the groups attached to the phosphate can be easily removed by esterases, proteases or other enzymes. In some embodiments, the groups attached to the phosphate can be removed by simple hydrolysis. Inside the cell, the monophosphate or mono-thiophosphate thus released may then be metabolized by cellular enzymes to the diphosphate or the active triphosphate, or the α-thiodiphosphate or the active α-thiotriphosphate, respectively. Furthermore, in some embodiments, varying the substituents on a cyclic nucleotide analog compound described herein, such as compound of Formula (I), can help maintain the efficacy of such compounds by reducing undesirable effects, such as isomerization.

[0141] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can act as a chain terminator of HCV replication. For example, incorporation of a compound of Formula (I) containing a moiety at the 2′-carbon position can terminate further elongation of the RNA chain of HCV. For example, a compound of Formula (I) can contain a 2′-carbon modification wherein R⁷ is a non-hydrogen group selected from halogen or an optionally substituted C_1-6 alkyl.

[0142] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can have increased metabolic and/or plasma stability. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be more resistant to hydrolysis and/or more resistant to enzymatic transformations. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can have improved properties. A non-limiting list of example properties include, but are not limited to, increased biological half life, increased bioavailability, increase potency, a sustained in vivo response, increased dosing intervals, decreased dosing amounts, decreased cytotoxicity, reduction in required amounts for treating disease conditions, reduction in viral load, reduction in time to seroconversion (i.e., the virus becomes undetectable in patient serum), increased sustained viral response, a reduction of morbidity or mortality in clinical outcomes, increased subject compliance, decreased liver conditions (such as liver fibrosis, liver cirrohis and/or liver cancer), and compatibility with other medications. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can have more potent antiviral activity (for example, a lower IC₅₀ in an HCV replicon assay) as compared to the current standard of care.

[0143] Additionally, in some embodiments, the presence of a phosphorothioate, phosphoramidate or phosphorothioamidate in a compound of Formula (I) can increase the stability of the compound by inhibiting its degradation. Also, in some embodiments, the presence of a phosphorothioate, phosphoramidate or phosphorothioamidate can make the compound more resistant to cleavage in vivo and provide sustained, extended efficacy. In some embodiments, a phosphorothioate, phosphoramidate or phosphorothioamidate can facilitate the penetration of the cell membrane by a compound of Formula (I) by making the compound more lipophilic.

[0144] Some embodiments described herein relates to a pharmaceutical composition, that can include a therapeutically effective amount of one or more compounds described herein (e.g., a compound of Formula (I), or a pharmaceutically acceptable salt thereof) and a pharmaceutically acceptable carrier, diluent, excipient or combination thereof. In some embodiments, the pharmaceutical composition can include a single diastereomer of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, (for example, a single diastereomer is present in the pharmaceutical composition at a concentration of greater than 99% compared to the total concentration of the other diastereomers). In other embodiments, the pharmaceutical composition can include a mixture of diastereomers of a compound of Formula (I), or a pharmaceutically acceptable salt thereof. For example, the pharmaceutical composition can include a concentration of one diastereomer of >50%, ≧60%, ≧70%, ≧80%, ≧90%, ≧95%, or ≧98%, as compared to the total concentration of the other diastereomers. In some embodiments, the pharmaceutical composition includes a 1:1 mixture of two diastereomers of a compound of Formula (I), or a pharmaceutically acceptable salt thereof.

[0145] The term “pharmaceutical composition” refers to a mixture of one or more compounds disclosed herein with other chemical components, such as diluents or carriers. The pharmaceutical composition facilitates administration of the compound to an organism. Pharmaceutical compositions can also be obtained by reacting compounds with inorganic or organic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, methanesulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, and salicylic acid. Pharmaceutical compositions will generally be tailored to the specific intended route of administration.

[0146] The term “physiologically acceptable” defines a carrier, diluent or excipient that does not abrogate the biological activity and properties of the compound.

[0147] As used herein, a “carrier” refers to a compound that facilitates the incorporation of a compound into cells or tissues. For example, without limitation, dimethyl sulfoxide (DMSO) is a commonly utilized carrier that facilitates the uptake of many organic compounds into cells or tissues of a subject.

[0148] As used herein, a “diluent” refers to an ingredient in a pharmaceutical composition that lacks pharmacological activity but may be pharmaceutically necessary or desirable. For example, a diluent may be used to increase the bulk of a potent drug whose mass is too small for manufacture and/or administration. It may also be a liquid for the dissolution of a drug to be administered by injection, ingestion or inhalation. A common form of diluent in the art is a buffered aqueous solution such as, without limitation, phosphate buffered saline that mimics the composition of human blood.

[0149] As used herein, an “excipient” refers to an inert substance that is added to a pharmaceutical composition to provide, without limitation, bulk, consistency, stability, binding ability, lubrication, disintegrating ability etc., to the composition. A “diluent” is a type of excipient.

[0150] The pharmaceutical compositions described herein can be administered to a human patient per se, or in pharmaceutical compositions where they are mixed with other active ingredients, as in combination therapy, or carriers, diluents, excipients or combinations thereof. Proper formulation is dependent upon the route of administration chosen. Techniques for formulation and administration of the compounds described herein are known to those skilled in the art.

[0151] The pharmaceutical compositions disclosed herein may be manufactured in a manner that is itself known, e.g., by means of conventional mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping or tableting processes. Additionally, the active ingredients are contained in an amount effective to achieve its intended purpose. Many of the compounds used in the pharmaceutical combinations disclosed herein may be provided as salts with pharmaceutically compatible counterions.

[0152] Multiple techniques of administering a compound exist in the art including, but not limited to, oral, rectal, topical, aerosol, injection and parenteral delivery, including intramuscular, subcutaneous, intravenous, intramedullary injections, intrathecal, direct intraventricular, intraperitoneal, intranasal and intraocular injections.

[0153] One may also administer the compound in a local rather than systemic manner, for example, via injection of the compound directly into the infected area, often in a depot or sustained release formulation. Furthermore, one may administer the compound in a targeted drug delivery system, for example, in a liposome coated with a tissue-specific antibody. The liposomes will be targeted to and taken up selectively by the organ.

[0154] The compositions may, if desired, be presented in a pack or dispenser device which may contain one or more unit dosage forms containing the active ingredient. The pack may for example comprise metal or plastic foil, such as a blister pack. The pack or dispenser device may be accompanied by instructions for administration. The pack or dispenser may also be accompanied with a notice associated with the container in form prescribed by a governmental agency regulating the manufacture, use, or sale of pharmaceuticals, which notice is reflective of approval by the agency of the form of the drug for human or veterinary administration. Such notice, for example, may be the labeling approved by the U.S. Food and Drug Administration for prescription drugs, or the approved product insert. Compositions that can include a compound described herein formulated in a compatible pharmaceutical carrier may also be prepared, placed in an appropriate container, and labeled for treatment of an indicated condition.

[0155] Some embodiments disclosed herein relate to a method of treating and/or ameliorating a disease or condition that can include administering to a subject a therapeutically effective amount of one or more compounds described herein, such as a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound described herein, or a pharmaceutically acceptable salt thereof.

[0156] Some embodiments disclosed herein relate to a method of ameliorating or treating a neoplastic disease that can include administering to a subject suffering from a neoplastic disease a therapeutically effective amount of one or more compounds described herein (e.g., a compound of Formula (I), or a pharmaceutically acceptable salt thereof), or a pharmaceutical composition that includes a compound described herein, or a pharmaceutically acceptable salt thereof. In some embodiments, the neoplastic disease can be cancer. In some embodiments, the neoplastic disease can be a tumor such as a solid tumor. In some embodiments, the neoplastic disease can be leukemia. Exemplary leukemias include, but are not limited to, acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML) and juvenile myelomonocytic leukemia (JMML).

[0157] Some embodiments disclosed herein relate to a method of inhibiting the growth of a tumor that can include administering to a subject having a tumor a therapeutically effective amount of one or more compounds described herein (for example, a compound of Formula (I)), or a pharmaceutical composition that includes one or more compounds described herein, or a pharmaceutically acceptable salt thereof.

[0158] Other embodiments disclosed herein relates to a method of ameliorating or treating a viral infection that can include administering to a subject suffering from a viral infection a therapeutically effective amount of one or more compounds described herein (for example, a compound of Formula (I)), or a pharmaceutical composition that includes one or more compounds described herein, or a pharmaceutically acceptable salt thereof. In some embodiments, the viral infection can be caused by a virus selected from an adenovirus, an Alphaviridae, an Arbovirus, an Astrovirus, a Bunyaviridae, a Coronaviridae, a Filoviridae, a Flaviviridae, a Hepadnaviridae, a Herpesviridae, an Alphaherpesvirinae, a Betaherpesvirinae, a Gammaherpesvirinae, a Norwalk Virus, an Astroviridae, a Caliciviridae, an Orthomyxoviridae, a Paramyxoviridae, a ParamyxoViruses, a Rubulavirus, a Morbillivirus, a Papovaviridae, a Parvoviridae, a Picornaviridae, an Aphthoviridae, a Cardioviridae, an Enteroviridae, a Coxsackie virus, a Polio Virus, a Rhinoviridae, a Phycodnaviridae, a Poxyiridae, a Reoviridae, a Rotavirus, a Retroviridae, an A-Type Retrovirus, an Immunodeficiency Virus, a Leukemia Viruses, an Avian Sarcoma Viruses, a Rhabdoviruses, a Rubiviridae, a Togaviridae an Arenaviridae and/or a Bornaviridae. In some embodiments, the viral infection can be a hepatitis C viral (HCV) infection. In other embodiments, the viral infection can be influenza. In still other embodiments, the viral infection can be HIV.

[0159] Some embodiments disclosed herein relate to methods of ameliorating and/or treating a viral infection that can include contacting a cell infected with the virus with an effective amount of one or more compounds described herein, or a pharmaceutically acceptable salt of a compound described herein, or a pharmaceutical composition that includes one or more compounds described herein, or a pharmaceutically acceptable salt thereof. Other embodiments described herein relate to using one or more compounds described herein, or a pharmaceutically acceptable salt of a compound described herein, in the manufacture of a medicament for ameliorating and/or treating a viral infection that can include contacting a cell infected with the virus with an effective amount of said compound(s). Still other embodiments described herein relate to one or more compounds described herein, or a pharmaceutically acceptable salt of a compound described herein, that can be used for ameliorating and/or treating a viral infection by contacting a cell infected with the virus with an effective amount of said compound(s). In some embodiments, the compound can be a compound of Formula (I), or a pharmaceutical acceptable salt thereof. In other embodiments, the compound can be a mono-, di- and/or tri-phosphate of a compound of Formula (I), or a pharmaceutically acceptable salt of the foregoing. In some embodiments, the virus can be a HCV virus.

[0160] Some embodiments disclosed herein relate to methods of inhibiting replication of a virus that can include contacting a cell infected with the virus with an effective amount of one or more compounds described herein, or a pharmaceutically acceptable salt of a compound described herein, or a pharmaceutical composition that includes one or more compounds described herein, or a pharmaceutically acceptable salt thereof. Other embodiments described herein relate to using one or more compounds described herein, or a pharmaceutically acceptable salt of a compound described herein, in the manufacture of a medicament for inhibiting replication of a virus that can include contacting a cell infected with the virus with an effective amount of said compound(s). Still other embodiments described herein relate to a compound described herein, or a pharmaceutically acceptable salt of a compound described herein, that can be used for inhibiting replication of a virus by contacting a cell infected with the virus with an effective amount of said compound(s). In some embodiments, the compound can be a compound of Formula (I), or a pharmaceutical acceptable salt thereof. In other embodiments, the compound can be a mono-, di- and/or tri-phosphate of a compound of Formula (I), or a pharmaceutically acceptable salt of the foregoing. In some embodiments, the virus can be a HCV virus.

[0161] HCV is an enveloped positive strand RNA virus in the Flaviviridae family. There are various nonstructural proteins of HCV, such as NS2, NS3, NS4, NS4A, NS4B, NS5A, and NS5B. NS5B is believed to be an RNA-dependent RNA polymerase involved in the replication of HCV RNA.

[0162] Some embodiments described herein relate to a method of inhibiting NS5B polymerase activity that can include contacting a cell (for example, a cell infected with HCV) with an effective amount of a compound of Formula (I), or a pharmaceutical acceptable salt thereof. Some embodiments described herein relate to a method of inhibiting NS5B polymerase activity that can include administering a cell (for example, a cell infected with HCV) with an effective amount of a compound of Formula (I), or a pharmaceutical acceptable salt thereof. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can inhibit a RNA dependent RNA polymerase. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can inhibit a HCV polymerase (for example, NS5B polymerase).

[0163] Some embodiments described herein relate to a method of treating HCV infection in a subject suffering from a HCV infection that can include administering to the subject an effective amount of a compound of Formula (I), or a pharmaceutical acceptable salt thereof, or a pharmaceutical composition that includes an effective amount of a compound of Formula (I), or a pharmaceutical acceptable salt thereof. Some embodiments described herein relate to a method of treating a condition selected from liver fibrosis, liver cirrohis, and liver cancer in a subject suffering from one or more of the aforementioned liver conditions that can include administering to the subject an effective amount of a compound or a pharmaceutical composition described herein (for example, a compound of Formula (I), or a pharmaceutical acceptable salt thereof). One cause of liver fibrosis, liver cirrohis, and/or liver cancer can be a HCV infection. Some embodiments described herein relate to a method of increasing liver function in a subject having a HCV infection that can include administering to the subject an effective amount of a compound or a pharmaceutical composition described herein (for example, a compound of Formula (I), or a pharmaceutical acceptable salt thereof). Also contemplated is a method for reducing or eliminating further virus-caused liver damage in a subject having an HCV infection by administering to the subject an effective amount of a compound or a pharmaceutical composition described herein (for example, a compound of Formula (I), or a pharmaceutical acceptable salt thereof). In some embodiments, this method can include slowing or halting the progression of liver disease. In other embodiments, the course of the disease can be reversed, and stasis or improvement in liver function is contemplated.

[0164] There are a variety of genotypes of HCV, and a variety of subtypes within each genotype. For example, at present it is known that there are eleven (numbered 1 through 11) main genotypes of HCV, although others have classified the genotypes as 6 main genotypes. Each of these genotypes is further subdivided into subtypes (1a-1c; 2a-2c; 3a-3b; 4a-4-e; 5a; 6a; 7a-7b; 8a-8b; 9a; 10a; and 11a). In some embodiments, an effective amount of a compound of Formula (I), or a pharmaceutical acceptable salt thereof, or a pharmaceutical composition that includes an effective amount of a compound of Formula (I), or a pharmaceutical acceptable salt thereof, can be effective to treat at least one genotype of HCV. In some embodiments, a compound described herein (for example, a compound of Formula (I), or a pharmaceutical acceptable salt thereof) can be effective to treat all 11 genotypes of HCV. In some embodiments, a compound described herein (for example, a compound of Formula (I), or a pharmaceutical acceptable salt thereof) can be effective to treat 3 or more, 5 or more, 7 or more, or 9 or more genotypes of HCV. In some embodiments, a compound of Formula (I), or a pharmaceutical acceptable salt thereof can be more effective against a larger number of HCV genotypes than the standard of care. In some embodiments, a compound of Formula (I), or a pharmaceutical acceptable salt thereof, can be more effective against a particular HCV genotype than the standard of care (such as genotype 1, 2, 3, 4, 5 and/or 6).

[0165] Various indicators for determining the effectiveness of a method for treating a HCV infection are known to those skilled in the art. Examples of suitable indicators include, but are not limited to, a reduction in viral load, a reduction in viral replication, a reduction in time to seroconversion (virus undetectable in patient serum), an increase in the rate of sustained viral response to therapy, a reduction of morbidity or mortality in clinical outcomes, a reduction in the rate of liver function decrease; stasis in liver function; improvement in liver function; reduction in one or more markers of liver dysfunction, including alanine transaminase, aspartate transaminase, total bilirubin, conjugated bilirubin, gamma glutamyl transpeptidase, and/or other indicator of disease response. Similarly, successful therapy with an effective amount of a compound or a pharmaceutical composition described herein (for example, a compound of Formula (I), or a pharmaceutical acceptable salt thereof) can reduce the incidence of liver cancer in HCV infected subjects.

[0166] In some embodiments, an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, is an amount that is effective to reduce viral titers to undetectable levels, for example, to about 1000 to about 5000, to about 500 to about 1000, or to about 100 to about 500 genome copies/mL serum. In some embodiments, an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, is an amount that is effective to reduce viral load compared to the viral load before administration of the compound of Formula (I), or a pharmaceutically acceptable salt thereof. For example, wherein the viral load is measured before administration of the compound of Formula (I), or a pharmaceutically acceptable salt thereof, and again after completion of the treatment regime with the compound of Formula (I), or a pharmaceutically acceptable salt thereof (for example, 1 month after completion). In some embodiments, an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be an amount that is effective to reduce viral load to lower than about 100 genome copies/mL serum. In some embodiments, an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, is an amount that is effective to achieve a reduction in viral titer in the serum of the subject in the range of about 1.5-log to about a 2.5-log reduction, about a 3-log to about a 4-log reduction, or a greater than about 5-log reduction compared to the viral load before administration of the compound of Formula (I), or a pharmaceutically acceptable salt thereof. For example, the viral load can be measured before administration of the compound of Formula (I), or a pharmaceutically acceptable salt thereof, and again after completion of the treatment regime with the compound of Formula (I), or a pharmaceutically acceptable salt thereof (for example, 1 month after completion).

[0167] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can result in at least a 1, 2, 3, 4, 5, 10, 15, 20, 25, 50, 75, 100-fold or more reduction in the replication of HCV relative to pre-treatment levels in a subject, as determined after completion of the treatment regime (for example 1 month after completion). In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can result in a reduction of the replication of HCV relative to pre-treatment levels in the range of about 2 to about 5 fold, about 10 to about 20 fold, about 15 to about 40 fold, or about 50 to about 100 fold. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can result in a reduction of HCV replication in the range of 1 to 1.5 log, 1.5 log to 2 log, 2 log to 2.5 log, 2.5 to 3 log, 3 log to 3.5 log or 3.5 to 4 log more reduction of HCV replication compared to the reduction of HCV reduction achieved by pegylated interferon in combination with ribavirin, administered according to the standard of care, or may achieve the same reduction as that standard of care therapy in a shorter period of time, for example, in one month, two months, or three months, as compared to the reduction achieved after six months of standard of care therapy with ribavirin and pegylated interferon.

[0168] In some embodiments, an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, is an amount that is effective to achieve a sustained viral response, for example, non-detectable or substantially non-detectable HCV RNA (e.g., less than about 500, less than about 400, less than about 200, or less than about 100 genome copies per milliliter serum) is found in the subject's serum for a period of at least about one month, at least about two months, at least about three months, at least about four months, at least about five months, or at least about six months following cessation of therapy.

[0169] In some embodiments, a therapeutically effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can reduce a level of a marker of liver fibrosis by at least about 10%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, or at least about 80%, or more, compared to the level of the marker in an untreated subject, or to a placebo-treated subject. Methods of measuring serum markers are known to those skilled in the art and include immunological-based methods, e.g., enzyme-linked immunosorbent assays (ELISA), radioimmunoassays, and the like, using antibody specific for a given serum marker. A non-limiting list of example markers includes measuring the levels of serum alanine aminotransferase (ALT), asparatate aminotransferacse (AST), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT) and total bilirubin (TBIL) using known methods. In general, an ALT level of less than about 45 IU/L (international units/liter), an AST in the range of 10-34 IU/L, ALP in the range of 44-147 IU/L, GGT in the range of 0-51 IU/L, TBIL in the range of 0.3-1.9 mg/dL is considered normal. In some embodiments, an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be an amount effective to reduce ALT, AST, ALP, GGT and/or TBIL levels to with what is considered a normal level.

[0170] Subjects who are clinically diagnosed with HCV infection include “naïve” subjects (e.g., subjects not previously treated for HCV, particularly those who have not previously received IFN-alpha-based and/or ribavirin-based therapy) and individuals who have failed prior treatment for HCV (“treatment failure” subjects). Treatment failure subjects include “non-responders” (i.e., subjects in whom the HCV titer was not significantly or sufficiently reduced by a previous treatment for HCV (≦0.5 log IU/mL), for example, a previous IFN-alpha monotherapy, a previous IFN-alpha and ribavirin combination therapy, or a previous pegylated IFN-alpha and ribavirin combination therapy); and “relapsers” (i.e., subjects who were previously treated for HCV, for example, who received a previous IFN-alpha monotherapy, a previous IFN-alpha and ribavirin combination therapy, or a previous pegylated IFN-alpha and ribavirin combination therapy, whose HCV titer decreased, and subsequently increased).

[0171] In some embodiments, a compound of Formtula (I), or a pharmaceutically acceptable salt thereof, can be administered to a treatment failure subject suffering from HCV. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered to a non-responder subject suffering from HCV. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered to a relapsed subject suffering from HCV.

[0172] After a period of time, infectious agents can develop resistance to one or more therapeutic agents. The term “resistance” as used herein refers to a viral strain displaying a delayed, lessened and/or null response to a therapeutic agent(s). For example, after treatment with an antiviral agent, the viral load of a subject infected with a resistant virus may be reduced to a lesser degree compared to the amount in viral load reduction exhibited by a subject infected with a non-resistant strain. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered to a subject infected with an HCV strain that is resistant to one or more different anti-HCV agents. In some embodiments, development of resistant HCV strains is delayed when a subject is treated with a compound of Formula (I), or a pharmaceutically acceptable salt thereof, compared to the development of HCV strains resistant to other HCV drugs.

[0173] In some embodiments, an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered to a subject for whom other anti-HCV medications are contraindicated. For example, administration of pegylated interferon alpha in combination with ribavirin is contraindicated in subjects with hemoglobinopathies (e.g., thalassemia major, sickle-cell anemia) and other subjects at risk from the hematologic side effects of current therapy. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be provided to a subject that is hypersensitive to interferon and/or ribavirin.

[0174] Some subjects being treated for HCV experience a viral load rebound. The term “viral load rebound” as used herein refers to a sustained ≧0.5 log IU/mL increase of viral load above nadir before the end of treatment, where nadir is a ≧0.5 log IU/mL decrease from baseline. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered to a subject experiencing viral load rebound, or can prevent such viral load rebound when used to treat the subject.

[0175] The standard of care for treating HCV has been associated with several side effects (adverse events). In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can decrease the number and/or severity of a side effect that can be observed in HCV patients being treated with ribavirin and pegylated interferon according to the standard of care. Examples of side effects include, but are not limited to fever, malaise, tachycardia, chills, headache, arthralgias, myalgias, fatigue, apathy, loss of apetite, nausea, vomiting, cognitive changes, asthenia, drowsiness, lack of initiative, irritability, confusion, depression, severe depression, suicidal ideation, anemia, low white blood cell counts, and thinning of hair. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be provided to a subject that discontinued a HCV therapy because of one or more adverse effects or side effects associated with one or more other HCV agents.

[0176] Table 4 provides some embodiments of the percentage improvement obtained using a compound of Formula (I), or a pharmaceutically acceptable salt thereof, as compared to the standard of care. Examples include the following: in some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, results in a percentage of non-responders that is 10% less than the percentage of non-responders receiving the standard of care; in some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, results in a number of side effects that is in the range of about 10% to about 30% less than compared to the number of side effects experienced by a subject receiving the standard of care; and in some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, results in a severity of a side effect (such as one of those described herein) that is 25% less than compared to the severity of the same side effect experienced by a subject receiving the standard of care. Methods of quantifying the severity of a side effect are known to those skilled in the art.

TABLE 4
Percentage	Percentage	Percentage	Percentage	Number	Severity
of non-	of	of	of viral load	of side	of side
responders	relapsers	resistance	rebound	effects	effects
10% less	10% less	10% less	10% less	10% less	10% less
25% less	25% less	25% less	25% less	25% less	25% less
40% less	40% less	40% less	40% less	40% less	40% less
50% less	50% less	50% less	50% less	50% less	50% less
60% less	60% less	60% less	60% less	60% less	60% less
70% less	70% less	70% less	70% less	70% less	70% less
80% less	80% less	80% less	80% less	80% less	80% less
90% less	90% less	90% less	90% less	90% less	90% less
about 10%	about 10%	about 10%	about 10% to	about 10%	about 10%
to about	to about	to about	about 30%	to about	to about
30% less	30% less	30% less	less	30% less	30% less
about 20%	about 20%	about 20%	about 20% to	about 20%	about 20%
to about	to about	to about	about 50%	to about	to about
50% less	50% less	50% less	less	50% less	50% less
about 30%	about 30%	about 30%	about 30% to	about 30%	about 30%
to about	to about	to about	about 70%	to about	to about
70% less	70% less	70% less	less	70% less	70% less
about 20%	about 20%	about 20%	about 20% to	about 20%	about 20%
to about	to about	to about	about 80%	to about	to about
80% less	80% less	80% less	less	80% less	80% less

[0177] Yet still other embodiments disclosed herein relate to a method of ameliorating or treating a parasitic disease that can include administering to a subject suffering from a parasitic disease a therapeutically effective amount of one or more compounds described herein (for example, a compound of Formula (I)), or a pharmaceutical composition that includes one or more compounds described herein. In some embodiments, the parasite disease can be Chagas' disease.

[0178] As used herein, a “subject” refers to an animal that is the object of treatment, observation or experiment. “Animal” includes cold- and warm-blooded vertebrates and invertebrates such as fish, shellfish, reptiles and, in particular, mammals. “Mammal” includes, without limitation, mice, rats, rabbits, guinea pigs, dogs, cats, sheep, goats, cows, horses, primates, such as monkeys, chimpanzees, and apes, and, in particular, humans. In some embodiments, the subject is human.

[0179] As used herein, the terms “treating,” “treatment,” “therapeutic,” or “therapy” do not necessarily mean total cure or abolition of the disease or condition. Any alleviation of any undesired signs or symptoms of a disease or condition, to any extent can be considered treatment and/or therapy. Furthermore, treatment may include acts that may worsen the patient's overall feeling of well-being or appearance.

[0180] The terms “therapeutically effective amount” and “effective amount” are used to indicate an amount of an active compound, or pharmaceutical agent, that elicits the biological or medicinal response indicated. For example, a therapeutically effective amount of compound can be the amount needed to prevent, alleviate or ameliorate symptoms of disease or prolong the survival of the subject being treated. This response may occur in a tissue, system, animal or human and includes alleviation of the signs or symptoms of the disease being treated. Determination of a therapeutically effective amount is well within the capability of those skilled in the art, in view of the disclosure provided herein. The therapeutically effective amount of the compounds disclosed herein required as a dose will depend on the route of administration, the type of animal, including human, being treated, and the physical characteristics of the specific animal under consideration. The dose can be tailored to achieve a desired effect, but will depend on such factors as weight, diet, concurrent medication and other factors which those skilled in the medical arts will recognize.

[0181] As will be readily apparent to one skilled in the art, the useful in vivo dosage to be administered and the particular mode of administration will vary depending upon the age, weight, the severity of the affliction, and mammalian species treated, the particular compounds employed, and the specific use for which these compounds are employed. The determination of effective dosage levels, that is the dosage levels necessary to achieve the desired result, can be accomplished by one skilled in the art using routine methods, for example, human clinical trials and in vitro studies.

[0182] The dosage may range broadly, depending upon the desired effects and the therapeutic indication. Alternatively dosages may be based and calculated upon the surface area of the patient, as understood by those of skill in the art. Although the exact dosage will be determined on a drug-by-drug basis, in most cases, some generalizations regarding the dosage can be made. The daily dosage regimen for an adult human patient may be, for example, an oral dose of between 0.01 mg and 3000 mg of each active ingredient, preferably between 1 mg and 700 mg, e.g. 5 to 200 mg. The dosage may be a single one or a series of two or more given in the course of one or more days, as is needed by the subject. In some embodiments, the compounds will be administered for a period of continuous therapy, for example for a week or more, or for months or years. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered less frequently compared to the frequency of administration of an agent within the standard of care. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered one time per day. For example, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered one time per day to a subject suffering from a HCV infection. In some embodiments, the total time of the treatment regime with a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can less compared to the total time of the treatment regime with the standard of care.

[0183] In instances where human dosages for compounds have been established for at least some condition, those same dosages may be used, or dosages that are between about 0.1% and 500%, more preferably between about 25% and 250% of the established human dosage. Where no human dosage is established, as will be the case for newly-discovered pharmaceutical compositions, a suitable human dosage can be inferred from ED₅₀ or ID₅₀ values, or other appropriate values derived from in vitro or in vivo studies, as qualified by toxicity studies and efficacy studies in animals.

[0184] In cases of administration of a pharmaceutically acceptable salt, dosages may be calculated as the free base. As will be understood by those of skill in the art, in certain situations it may be necessary to administer the compounds disclosed herein in amounts that exceed, or even far exceed, the above-stated, preferred dosage range in order to effectively and aggressively treat particularly aggressive diseases or infections.

[0185] Dosage amount and interval may be adjusted individually to provide plasma levels of the active moiety which are sufficient to maintain the modulating effects, or minimal effective concentration (MEC). The MEC will vary for each compound but can be estimated from in vitro data. Dosages necessary to achieve the MEC will depend on individual characteristics and route of administration. However, HPLC assays or bioassays can be used to determine plasma concentrations. Dosage intervals can also be determined using MEC value. Compositions should be administered using a regimen which maintains plasma levels above the MEC for 10-90% of the time, preferably between 30-90% and most preferably between 50-90%. In cases of local administration or selective uptake, the effective local concentration of the drug may not be related to plasma concentration.

[0186] It should be noted that the attending physician would know how to and when to terminate, interrupt, or adjust administration due to toxicity or organ dysfunctions. Conversely, the attending physician would also know to adjust treatment to higher levels if the clinical response were not adequate (precluding toxicity). The magnitude of an administrated dose in the management of the disorder of interest will vary with the severity of the condition to be treated and to the route of administration. The severity of the condition may, for example, be evaluated, in part, by standard prognostic evaluation methods. Further, the dose and perhaps dose frequency, will also vary according to the age, body weight, and response of the individual patient. A program comparable to that discussed above may be used in veterinary medicine.

[0187] Compounds disclosed herein can be evaluated for efficacy and toxicity using known methods. For example, the toxicology of a particular compound, or of a subset of the compounds, sharing certain chemical moieties, may be established by determining in vitro toxicity towards a cell line, such as a mammalian, and preferably human, cell line. The results of such studies are often predictive of toxicity in animals, such as mammals, or more specifically, humans. Alternatively, the toxicity of particular compounds in an animal model, such as mice, rats, rabbits, or monkeys, may be determined using known methods. The efficacy of a particular compound may be established using several recognized methods, such as in vitro methods, animal models, or human clinical trials. When selecting a model to determine efficacy, the skilled artisan can be guided by the state of the art to choose an appropriate model, dose, route of administration and/or regime.

[0188] In some embodiments, the compounds disclosed herein, such as a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound described herein, or a pharmaceutically acceptable salt thereof, can be used in combination with one or more additional agent(s). Examples of additional agents that can be used in combination with a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, include, but are not limited to, agents currently used in a conventional standard of care for treating HCV, HCV protease inhibitors, HCV polymerase inhibitors, NS5A inhibitors, other antiviral compounds, compounds of Formula (AA) (including mono-, di, and/or tri-phosphates of Formula (AA), pharmaceutically acceptable salts and pharmaceutical compositions that can include a compound of Formula (AA), mono-, di- and/or tri-phosphates thereof, or a pharmaceutically acceptable salt of the foregoing), compounds of Formula (CC) (including pharmaceutically acceptable salts and pharmaceutical compositions that can include a compound of Formula (CC), or a pharmaceutically acceptable salt thereof), compounds of Formula (DD) (including pharmaceutically acceptable salts and pharmaceutical compositions that can include a compound of Formula (DD), or a pharmaceutically acceptable salt thereof), and/or combinations thereof. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used with one, two, three or more additional agents described herein. A non-limiting list of examples of combinations of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, is provided in Tables A, B, C and D.

[0189] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in combination with an agent(s) currently used in a conventional standard of care therapy. For example, for the treatment of HCV, a compound disclosed herein can be used in combination with Pegylated interferon-alpha-2a (brand name PEGASYS®) and ribavirin, or Pegylated interferon-alpha-2b (brand name PEG-INTRON®) and ribavirin. As another example, a compound disclosed herein can be used in combination with oseltamivir (TAMIFLU®) or zanamivin (RELENZA®) for treating an influenza infection.

[0190] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be substituted for an agent currently used in a conventional standard of care therapy. For example, for the treatment of HCV, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in place of ribavirin.

[0191] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in combination with an interferon, such as a pegylated interferon. Examples of suitable interferons include, but are not limited to, Pegylated interferon-alpha-2a (brand name PEGASYS®), Pegylated interferon-alpha-2b (brand name PEG-INTRON®), interferon alfacon-1 (brand name INFERGENO), pegylated interferon lambda and/or a combination thereof.

[0192] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in combination with a HCV protease inhibitor. A non-limiting list of example HCV protease inhibitors include the following: VX-950 (TELAPREVIR®), MK-5172, ABT-450, BILN-2061, BI-201335, BMS-650032, SCH 503034 (BOCEPREVIR®), GS-9256, GS-9451, IDX-320, ACH-1625, ACH-2684, TMC-435, ITMN-191 (DANOPREVIR®) and/or a combination thereof. A non-limiting list of example HCV protease inhibitors includes the compounds numbered 1001-1014 in FIGS. 1A-1B.

[0193] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in combination with a HCV polymerase inhibitor. In some embodiments, the HCV polymerase inhibitor can be a nucleoside inhibitor. In other embodiments, the HCV polymerase inhibitor can be a non-nucleoside inhibitor. Examples of suitable nucleoside inhibitors include, but are not limited to, RG7128, PSI-7851, PSI-7977, INX-189, PSI-352938, PSI-661, 4′-azidouridine (including known prodrugs of 4′-azidouridine), GS-6620, IDX-184 and TMC649128, and/or combinations thereof. A non-limiting list of example nucleoside inhibitors includes compounds numbered 2001-2010 in FIG. 2. Examples of suitable non-nucleoside inhibitors include, but are not limited to, ABT-333, ANA-598, VX-222, HCV-796, BI-207127, GS-9190, PF-00868554 (FILIBUVIR®), VX-497 and/or combinations thereof. A non-limiting list of example non-nucleoside inhibitors includes the compounds numbered 3001-3008 in FIG. 3.

[0194] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in combination with a NS5A inhibitor. A non-limiting list of example NS5A inhibitors include BMS-790052, PPI-461, ACH-2928, GS-5885, BMS-824393 and/or combinations thereof. A non-limiting list of example NS5A inhibitors includes the compounds numbered 4001-4005 in FIG. 4.

[0195] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in combination with other antiviral compounds. Examples of other antiviral compounds include, but are not limited to, Debio-025, MIR-122 and/or combinations thereof. A non-limiting list of example other antiviral compounds includes the compounds numbered 5001-5002 in FIG. 5.

[0196] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in combination with a compound of Formula (AA), mono-, di- and/or tri-phosphate thereof, or a pharmaceutically acceptable salt of the foregoing, or a pharmaceutical composition that includes a compound of Formula (AA), mono-, di- and/or tri-phosphate thereof, or a pharmaceutically acceptable salt of the foregoing (see, U.S. Application No. 13/236,450, filed Sep. 19, 2011, and U.S. Provisional Application Nos. 61/385,425, filed Sep. 22, 2010, and 61/426,467, filed Dec. 22, 2010, the contents of which are incorporated by reference in their

wherein B^AA1 can be an optionally substituted heterocyclic base or an optionally substituted heterocyclic base with a protected amino group; R^AA1 can be an optionally substituted N-linked amino acid or an optionally substituted N-linked amino acid ester derivative; R¹ be selected from an optionally substituted aryl, an optionally substituted heteroaryl and an optionally substituted heterocyclyl; R^AA3a and R^AA36 can be independently selected from hydrogen, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl, an optionally substituted C_1-6 haloalkyl and aryl(C_1-6 alkyl), provided that at least one of R^AA3a and R^AA3b is not hydrogen; or R^AA3a and R^AA3b can be taken together to form a group selected from an optionally substituted C_3-6 cycloalkyl, an optionally substituted C_3-6 cycloalkenyl, an optionally substituted C_3-6 aryl, and an optionally substituted C_3-6 heteroaryl; R^AA4 can be hydrogen; R^AA5 can be selected from hydrogen, —OR^AA9 and —OC(═O)R^AA10; R^AA6 can be selected from hydrogen, halogen, —OR^AA11 and —OC(═O)R^AA12; or R^AA5 and R^AA6 can be both oxygen atoms and linked together by a carbonyl group; R^AA7 can be selected from hydrogen, halogen, an optionally substituted C_1-6 alkyl, —OR^AA13 and —OC(═O)R^AA14; R^AA8 can be hydrogen or an optionally substituted C_1-6 alkyl; R^AA9, R^AA11 and R^AA13 can be independently selected from hydrogen and an optionally substituted C_1-6 alkyl; and R^AA10, R^AA12 and R^AA14 can be independently selected from an optionally substituted C_1-6 alkyl and an optionally substituted C_3-6 cycloalkyl. A non-limiting list of examples of compounds of Formula (AA), and phosphates thereof, includes the compounds numbered 7000-7077 in FIGS. 7A-7O. In some embodiments, Formula (AA) cannot be compound 7044, 7045, 7046, 7047, 7048, 7049, 7050, 7072, 7073, 7074, 7075, 7076 or 7077.

[0197] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in combination with a compound of Formula (CC), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (CC), or a pharmaceutically acceptable salt thereof (see, U.S. Application No. 13/236,435, filed Sep. 19, 2011, and U.S. Provisional Application Nos. 61/385,363, filed Sep. 22, 2010, and 61/426,461, filed Dec. 22, 2010, the contents of which are incorporated by reference in their entireties):

wherein B^CC1 can be an optionally substituted heterocyclic base or an optionally substituted heterocyclic base with a protected amino group; R^CC1 can be selected from O⁻, OH, an optionally substituted N-linked amino acid and an optionally substituted N-linked amino acid ester derivative; R^CC2 can be selected from an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted heterocyclyl and

wherein R^CC19, R^CC20 and R^CC21 can be independently absent or hydrogen, and n^CC can be 0 or 1; provided that when R^CC1 is O⁻ or OH, then R^CC2 is

R^CC3a and R^CC3b can be independently selected from hydrogen, deuterium, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl, an optionally substituted C_1-6 haloalkyl and aryl(C_1-6 alkyl); or R^CC3a and R^CC3b can be taken together to form an optionally substituted C_3-6 cycloalkyl; R^CC4 can be selected from hydrogen, azido, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl and an optionally substituted C_2-6 alkynyl; R^CC5 can be selected from hydrogen, halogen, azido, cyano, an optionally substituted C_1-6 alkyl, —OR^CC10 and —OC(═O)R^CC11; R^CC6 can be selected from hydrogen, halogen, azido, cyano, an optionally substituted C_1-6 alkyl, —OR^CC12 and —OC(═O)R^CC13; R^CC7 can be selected from hydrogen, halogen, azido, cyano, an optionally substituted C_1-6 alkyl, —OR^CC14 and —OC(═O)R^CC15; or R^CC6 and R^CC7 can be both oxygen atoms and linked together by a carbonyl group; R^CC8 can be selected from hydrogen, halogen, azido, cyano, an optionally substituted C_1-6 alkyl, —OR^CC16 and —OC(═O)R^CC17; R^CC9 can be selected from hydrogen, azido, cyano, an optionally substituted C_1-6 alkyl and —OR^CC18; R^CC10, R^CC12, R^CC14, R^CC16 and R^CC18 can be independently selected from hydrogen and an optionally substituted C_1-6 alkyl; and R^CC11, R^CC13, R^CC15 and R^CC17 can be independently selected from an optionally substituted C_1-6 alkyl and an optionally substituted C_3-6 cycloalkyl. In some embodiments, when R^CC3a, R^CC3b, R^CC4, R^CC5, R^CC7, R^CC8 and R^CC9 are all hydrogen, then R^CC6 is not azido. In some embodiments, R^CC2 cannot be

when R^CC3a is hydrogen, R^CC3b is hydrogen, R^CC4 is H, R^CC5 is OH or H, R^CC6 is hydrogen, OH, or —OC(═O)CH₃, R^CC7 is hydrogen, OH, OCH₃ or —OC(═O)CH₃, R^CC8 is hydrogen, OH or OCH₃, R^CC9 is H and B^CC1 is an optionally substituted adenine, an optionally substituted guanine, an optionally substituted uracil or an optionally substituted hypoxanthine. In some embodiments, R^CC2 cannot be

A non-limiting list of examples of compounds of Formula (CC) includes the compounds numbered 6000-6078 in FIGS. 6A-6M.

[0198] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be used in combination with a compound of Formula (DD), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (DD), or a pharmaceutically acceptable salt thereof (see, e.g., U.S. Publication No. 2010-0249068, filed Mar. 19, 2010, the contents of which are incorporated by reference in its entirety):

wherein each can be independently a double or single bond; A^DD1 can be selected from C (carbon), O (oxygen) and S (sulfur); B^DD1 can be an optionally substituted heterocyclic base or a derivative thereof; D^DD1 can be selected from C═CH₂, CH₂, O (oxygen), S (sulfur), CHF, and CF₂; R^DD1 can be hydrogen, an optionally substituted alkyl, an optionally substituted cycloalkyl, an optionally substituted aralkyl, dialkylaminoalkylene, alkyl-C(═O)—, aryl-C(═O)—, alkoxyalkyl-C(═O)—, aryloxyalkyl-C(═O)—, alkylsulfonyl, arylsulfonyl, aralkylsulfonyl,

an —O-linked amino acid, diphosphate, triphosphate or derivatives thereof; R^DD2 and R^DD3 can be each independently selected from hydrogen, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl and an optionally substituted C_1-6 haloalkyl, provided that at least one of R^DD2 and R^DD3 cannot be hydrogen; or R^DD2 and R^DD3 are taken together to form a group selected from among C_3-6 cycloalkyl, C_3-6 cycloalkenyl, C_3-6 aryl, and a C_3-6 heteroaryl; R^DD4 and R^DD9 can be independently selected from hydrogen, halogen, —NH₂, —NHR^DDa1, NR^DDa1R^DDb1, —OR^DDa1, —SR^DDa1, —CN, —NC, —N₃, —NO₂, —N(R^DDc1)—NR^DDa1R^DDb1, —N(R^DDc1)—OR^DDa1, —S—SR^DDa1, —(═O)R^DDa1, —C(═O)OR^DDa1, —C(═O)NR^DDa1R^DDb1, —O—(C═O)R^DDa1, —O—C(═O)OR^DDa1, —O—C(═O)NR^DDa1R^DDb1, —N(R^DDc1)—C(═O)NR^DDa1R^DDb1, —S(═O)R^DDa1, S(═O)₂R^DDa1, —O—S(═O)₂NR^DDa1R^DDb1, —N(R^DDc1)—S(═O)₂NR^DDa1R^DDb1, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl, an optionally substituted aralkyl and an —O-linked amino acid; R^DD5, R^DD6 and R^DD7 can be independently absent or selected from hydrogen, halogen, —NH₂, —NHR^DDa1, NR^DDa1R^DDb1, —OR^DDa1, —SR^DDa1, CN, —NC, —N₃, —NO₂, —N(R^DDc1)—NR^DDa1R^DDb1, —N(R^DDc1)—OR^DDa1, —S—SR^DDa1, —C(═O)R^DDa1, —C(═O)OR^DDa1, —C(═O)NR^DDa1R^DDb1, —O—(C═O)R^DDa1, —O—C(═O)OR^DDa1, —O—C(═O)NR^DDa1R^DDb1, —N(R^DDc1)—C(═O)NR^DDa1R^DDb1, —S(═O)R^DDa1, S(═O)₂R^DDa1, —O—S(═O)₂NR^DDa1R^DDb1, —N(R^DDc1)—S(═O)₂NR^DDa1R^DDb1, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl, an optionally substituted aralkyl and an —O-linked amino acid; or R^DD6 and R^DD7 taken together form —O—C(═O)—O—; R^DD8 can be absent or selected from hydrogen, halogen, —NH₂, —NHR^DDa1, NR^DDa1R^DDb1, —OR^DDa1, —SR^DDa1, —CN, —NC, —N₃, —NO₂, —N(R^DDc1)—NR^DDa1R^DDb1, —N(R^DDc1)—OR^DDa1, —S—SR^DDa1, —C(═O)R^DDa1, —C(═O)NR^DDa1R^DDb1, —O—C(═O)OR^DDa1, —O—C(═O)NR^DDa1R^DDb1, —N(R^DDc1)—C(═O)NR^DDa1R^DDb1, —S(═O)R^DDa1, S(═O)₂R^DDa1, —O—S(═O)₂NR^DDb1, —N(R^DDc1)—S(═O)₂NR^DDa1R^DDb1, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl, an optionally substituted haloalkyl, an optionally substituted hydroxyalkyl and an —O-linked amino acid, or when the bond to R^DD7 indicated by is a double bond, then R^DD7 is a C_2-6 alkylidene and R^DD8 is absent; R^DDa1, R^DDb1 and R^DDc1 can be each independently selected from hydrogen, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted aralkyl and an optionally substituted heteroaryl(C_1-6 alkyl); R^DD10 can be selected from O⁻, —OH, an optionally substituted aryloxy or aryl-O—,

alkyl-C(═O)—O—CH₂—O—, alkyl-C(═O)—S—CH₂CH₂—O— and an —N-linked amino acid; R^DD11 can be selected from O⁻, —OH, an optionally substituted aryloxy or aryl-O—,

alkyl-C(═O)—O—CH₂—O—, alkyl-C(═O)—S—CH₂CH₂—O— and an —N-linked amino acid; each R^DD12 and each R^DD13 can be independently —C≡N or an optionally substituted substituent selected from C_1-8 organylcarbonyl, C_1-8 alkoxycarbonyl and C_1-8 organylaminocarbonyl; each R^DD14 can be hydrogen or an optionally substituted C_1-6-alkyl; each m^DD can be independently 1 or 2, and if both R^DD10 and R^DD11 are

each R^DD12, each R^DD13, each R^DD14 and each m^DD can be the same or different. In some embodiments, R^DD8 can be halogen, —OR^DDa1, an optionally substituted C_1-6 alkyl, an optionally substituted C_2-6 alkenyl, an optionally substituted C_2-6 alkynyl and an optionally substituted C_1-6 haloalkyl.

[0199] Some embodiments described herein relate to a method of ameliorating or treating a viral infection that can include contacting a cell infected with the viral infection with a therapeutically effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more agents selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an antiviral compound, a compound of Formula (AA), a mono-, di, and/or tri-phosphate thereof, a compound of Formula (CC) and a compound of Formula (DD), or a pharmaceutically acceptable salt of any of the aforementioned compounds.

[0200] Some embodiments described herein relate to a method of ameliorating or treating a viral infection that can include administering to a subject suffering from the viral infection a therapeutically effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more agents selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an antiviral compound, a compound of Formula (AA), a mono-, di, and/or tri-phosphate thereof, a compound of Formula (CC) and a compound of Formula (DD), or a pharmaceutically acceptable salt of any of the aforementioned compounds.

[0201] Some embodiments described herein relate to a method of inhibiting viral replication of a virus that can include contacting a cell infected with the virus an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more agents selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an antiviral compound, a compound of Formula (AA), a mono-, di, and/or tri-phosphate thereof, a compound of Foimula (CC) and a compound of Formula (DD), or a pharmaceutically acceptable salt of any of the aforementioned compounds.

[0202] Some embodiments described herein relate to a method of ameliorating or treating a viral infection that can include contacting a cell infected with the viral infection with a therapeutically effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more agents selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an antiviral compound, a compound of Formula (AA), a compound of Formula (CC) and a compound of Formula (DD), or a pharmaceutically acceptable salt of any of the aforementioned compounds.

[0203] Some embodiments described herein relate to a method of ameliorating or treating a viral infection that can include administering to a subject suffering from the viral infection a therapeutically effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more agents selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an antiviral compound, a compound of Formula (AA), a compound of Formula (CC) and a compound of Formula (DD), or a pharmaceutically acceptable salt of any of the aforementioned compounds.

[0204] Some embodiments described herein relate to a method of inhibiting viral replication of a virus that can include contacting a cell infected with the virus an effective amount of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more agents selected from an interferon, ribavirin, a HCV protease inhibitor, a HCV polymerase inhibitor, a NS5A inhibitor, an antiviral compound, a compound of Formula (AA), a compound of Formula (CC) and a compound of Formula (DD), or a pharmaceutically acceptable salt of any of the aforementioned compounds.

[0205] In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered with one or more additional agent(s) together in a single pharmaceutical composition. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt the thereof, can be administered with one or more additional agent(s) as two or more separate pharmaceutical compositions. For example, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered in one pharmaceutical composition, and at least one of the additional agents can be administered in a second pharmaceutical composition. If there are at least two additional agents, one or more of the additional agents can be in a first pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, and at least one of the other additional agent(s) can be in a second pharmaceutical composition.

[0206] The dosing amount(s) and dosing schedule(s) when using a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, and one or more additional agents are within the knowledge of those skilled in the art. For example, when performing a conventional standard of care therapy using art-recognized dosing amounts and dosing schedules, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered in addition to that therapy, or in place of one of the agents of a combination therapy, using effective amounts and dosing protocols as described herein.

[0207] The order of administration of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, with one or more additional agent(s) can vary. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered prior to all additional agents. In other embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered prior to at least one additional agent. In still other embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered concomitantly with one or more additional agent(s). In yet still other embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered subsequent to the administration of at least one additional agent. In some embodiments, a compound of Formula (I), or a pharmaceutically acceptable salt thereof, can be administered subsequent to the administration of all additional agents.

[0208] In some embodiments, the combination of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) can result in an additive effect. In some embodiments, the combination of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) can result in a synergistic effect. In some embodiments, the combination of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) can result in a strongly synergistic effect. In some embodiments, the combination of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) is not antagonistic.

[0209] As used herein, the term “antagonistic” means that the activity of the combination of compounds is less compared to the sum of the activities of the compounds in combination when the activity of each compound is determined individually (i.e. as a single compound). As used herein, the term “synergistic effect” means that the activity of the combination of compounds is greater than the sum of the individual activities of the compounds in the combination when the activity of each compound is determined individually. As used herein, the term “additive effect” means that the activity of the combination of compounds is about equal to the sum of the individual activities of the compound in the combination when the activity of each compound is determined individually.

[0210] A potential advantage of utilizing a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) may be a reduction in the required amount(s) of one or more compounds of FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) that is effective in treating a disease condition disclosed herein (for example, HCV), as compared to the amount required to achieve same therapeutic result when one or more compounds of FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) are administered without a compound of Formula (I), or a pharmaceutically acceptable salt thereof. For example, the amount of a compound in FIGS. 1-7 and 9 (including a pharmaceutically acceptable salt and prodrug thereof), can be less compared to the amount of the compound in FIGS. 1-7 and 9 (including a pharmaceutically acceptable salt and prodrug thereof), needed to achieve the same viral load reduction when administered as a monotherapy. Another potential advantage of utilizing a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) is that the use of two or more compounds having different mechanism of actions can create a higher barrier to the development of resistant viral strains compared to the barrier when a compound is administered as monotherapy.

[0211] Additional advantages of utilizing a compound of Formula (I), or a pharmaceutically acceptable salt thereof, in combination with one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) may include little to no cross resistance between a compound of Formula (I), or a pharmaceutically acceptable salt thereof, and one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof) thereof; different routes for elimination of a compound of Formula (I), or a pharmaceutically acceptable salt thereof, and one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof); little to no overlapping toxicities between a compound of Formula (I), or a pharmaceutically acceptable salt thereof, and one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof); little to no significant effects on cytochrome P450; and/or little to no pharmacokinetic interactions between a compound of Formula (I), or a pharmaceutically acceptable salt thereof, and one or more additional agent(s) in FIGS. 1-7 and 9 (including pharmaceutically acceptable salts and prodrugs thereof).

[0212] A non-limiting list of example combination of compounds of Formula (I), or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition that includes a compound described herein, with one or more additional agent(s) are provided in Tables A, B, C and D. Each numbered X and Y compound in Tables A, B, C and D has a corresponding name and/or structure provided in FIGS. 1 to 9. The numbered compounds in Tables A, B, C and D includes pharmaceutically acceptable salts of the compounds and pharmaceutical compositions containing the compounds or a pharmaceutically acceptable salt thereof. For example, 1001 includes the compound corresponding to 1001, pharmaceutically acceptable salts thereof, and pharmaceutical compositions that include compound 1001 and/or a pharmaceutically acceptable salt thereof. The combinations exemplified in Tables A, B, C and D are designated by the formula X:Y, which represents a combination of a compound X with a compound Y. For example, the combination designated as 1001:8001 in Table A represents a combination of compound 1001 with compound 8001, including pharmaceutically acceptable salts of compound 1001 and/or 8001, and pharmaceutical compositions including compound 1001 and 8001 (including pharmaceutical compositions that include pharmaceutically acceptable salts of compound 1001 and/or compound 8001). Thus, the combination designated as 1001:8001 in Table A represents the combination of Telaprevir (compound 1001, as shown in FIG. 1A) and

(compound 8001, as shown in FIG. 8A), including pharmaceutically acceptable salts of compound 1001 and/or 8001, and pharmaceutical compositions including compound 1001 and 8001 (including pharmaceutical compositions that include pharmaceutically acceptable salts of compound 1001 and/or compound 8001). Each of the combinations provided in Tables A, B, C and D can be used with one, two, three or more additional agents described herein. In some embodimentsdescribed herein, the combination of agents can be used to treat, amerliorate and/or inhibit a virus and/or a viral infection, wherein the virus can be HCV and the viral infection can be an HCV viral infection.

TABLE A
Example combinations of a compound X with a compound Y.
X:Y
1001:8000
1002:8000
1003:8000
1004:8000
1005:8000
1006:8000
1007:8000
1008:8000
1009:8000
1010:8000
1011:8000
1012:8000
1013:8000
1014:8000
2001:8000
2002:8000
2003:8000
2004:8000
2005:8000
2006:8000
2007:8000
2008:8000
2009:8000
2010:8000
3001:8000
3002:8000
3003:8000
3004:8000
3005:8000
3006:8000
3007:8000
3008:8000
4001:8000
4002:8000
4003:8000
4004:8000
4005:8000
5001:8000
5002:8000
1001:8001
1002:8001
1003:8001
1004:8001
1005:8001
1006:8001
1007:8001
1008:8001
1009:8001
1010:8001
1011:8001
1012:8001
1013:8001
1014:8001
2001:8001
2002:8001
2003:8001
2004:8001
2005:8001
2006:8001
2007:8001
2008:8001
2009:8001
2010:8001
3001:8001
3002:8001
3003:8001
3004:8001
3005:8001
3006:8001
3007:8001
3008:8001
4001:8001
4002:8001
4003:8001
4004:8001
4005:8001
5001:8001
5002:8001
1001:8002
1002:8002
1003:8002
1004:8002
1005:8002
1006:8002
1007:8002
1008:8002
1009:8002
1010:8002
1011:8002
1012:8002
1013:8002
1014:8002
2001:8002
2002:8002
2003:8002
2004:8002
2005:8002
2006:8002
2007:8002
2008:8002
2009:8002
2010:8002
3001:8002
3002:8002
3003:8002
3004:8002
3005:8002
3006:8002
3007:8002
3008:8002
4001:8002
4002:8002
4003:8002
4004:8002
4005:8002
5001:8002
5002:8002
1001:8003
1002:8003
1003:8003
1004:8003
1005:8003
1006:8003
1007:8003
1008:8003
1009:8003
1010:8003
1011:8003
1012:8003
1013:8003
1014:8003
2001:8003
2002:8003
2003:8003
2004:8003
2005:8003
2006:8003
2007:8003
2008:8003
2009:8003
2010:8003
3001:8003
3002:8003
3003:8003
3004:8003
3005:8003
3006:8003
3007:8003
3008:8003
4001:8003
4002:8003
4003:8003
4004:8003
4005:8003
5001:8003
5002:8003
1001:8004
1002:8004
1003:8004
1004:8004
1005:8004
1006:8004
1007:8004
1008:8004
1009:8004
1010:8004
1011:8004
1012:8004
1013:8004
1014:8004
2001:8004
2002:8004
2003:8004
2004:8004
2005:8004
2006:8004
2007:8004
2008:8004
2009:8004
2010:8004
3001:8004
3002:8004
3003:8004
3004:8004
3005:8004
3006:8004
3007:8004
3008:8004
4001:8004
4002:8004
4003:8004
4004:8004
4005:8004
5001:8004
5002:8004
1001:8005
1002:8005
1003:8005
1004:8005
1005:8005
1006:8005
1007:8005
1008:8005
1009:8005
1010:8005
1011:8005
1012:8005
1013:8005
1014:8005
2001:8005
2002:8005
2003:8005
2004:8005
2005:8005
2006:8005
2007:8005
2008:8005
2009:8005
2010:8005
3001:8005
3002:8005
3003:8005
3004:8005
3005:8005
3006:8005
3007:8005
3008:8005
4001:8005
4002:8005
4003:8005
4004:8005
4005:8005
5001:8005
5002:8005
1001:8006
1002:8006
1003:8006
1004:8006
1005:8006
1006:8006
1007:8006
1008:8006
1009:8006
1010:8006
1011:8006
1012:8006
1013:8006
1014:8006
2001:8006
2002:8006
2003:8006
2004:8006
2005:8006
2006:8006
2007:8006
2008:8006
2009:8006
2010:8006
3001:8006
3002:8006
3003:8006
3004:8006
3005:8006
3006:8006
3007:8006
3008:8006
4001:8006
4002:8006
4003:8006
4004:8006
4005:8006
5001:8006
5002:8006
1001:8007
1002:8007
1003:8007
1004:8007
1005:8007
1006:8007
1007:8007
1008:8007
1009:8007
1010:8007
1011:8007
1012:8007
1013:8007
1014:8007
2001:8007
2002:8007
2003:8007
2004:8007
2005:8007
2006:8007
2007:8007
2008:8007
2009:8007
2010:8007
3001:8007
3002:8007
3003:8007
3004:8007
3005:8007
3006:8007
3007:8007
3008:8007
4001:8007
4002:8007
4003:8007
4004:8007
4005:8007
5001:8007
5002:8007
1001:8008
1002:8008
1003:8008
1004:8008
1005:8008
1006:8008
1007:8008
1008:8008
1009:8008
1010:8008
1011:8008
1012:8008
1013:8008
1014:8008
2001:8008
2002:8008
2003:8008
2004:8008
2005:8008
2006:8008
2007:8008
2008:8008
2009:8008
2010:8008
3001:8008
3002:8008
3003:8008
3004:8008
3005:8008
3006:8008
3007:8008
3008:8008
4001:8008
4002:8008
4003:8008
4004:8008
4005:8008
5001:8008
5002:8008
1001:8009
1002:8009
1003:8009
1004:8009
1005:8009
1006:8009
1007:8009
1008:8009
1009:8009
1010:8009
1011:8009
1012:8009
1013:8009
1014:8009
2001:8009
2002:8009
2003:8009
2004:8009
2005:8009
2006:8009
2007:8009
2008:8009
2009:8009
2010:8009
3001:8009
3002:8009
3003:8009
3004:8009
3005:8009
3006:8009
3007:8009
3008:8009
4001:8009
4002:8009
4003:8009
4004:8009
4005:8009
5001:8009
5002:8009
1001:8010
1002:8010
1003:8010
1004:8010
1005:8010
1006:8010
1007:8010
1008:8010
1009:8010
1010:8010
1011:8010
1012:8010
1013:8010
1014:8010
2001:8010
2002:8010
2003:8010
2004:8010
2005:8010
2006:8010
2007:8010
2008:8010
2009:8010
2010:8010
3001:8010
3002:8010
3003:8010
3004:8010
3005:8010
3006:8010
3007:8010
3008:8010
4001:8010
4002:8010
4003:8010
4004:8010
4005:8010
5001:8010
5002:8010
1001:8011
1002:8011
1003:8011
1004:8011
1005:8011
1006:8011
1007:8011
1008:8011
1009:8011
1010:8011
1011:8011
1012:8011
1013:8011
1014:8011
2001:8011
2002:8011
2003:8011
2004:8011
2005:8011
2006:8011
2007:8011
2008:8011
2009:8011
2010:8011
3001:8011
3002:8011
3003:8011
3004:8011
3005:8011
3006:8011
3007:8011
3008:8011
4001:8011
4002:8011
4003:8011
4004:8011
4005:8011
5001:8011
5002:8011
1001:8012
1002:8012
1003:8012
1004:8012
1005:8012
1006:8012
1007:8012
1008:8012
1009:8012
1010:8012
1011:8012
1012:8012
1013:8012
1014:8012
2001:8012
2002:8012
2003:8012
2004:8012
2005:8012
2006:8012
2007:8012
2008:8012
2009:8012
2010:8012
3001:8012
3002:8012
3003:8012
3004:8012
3005:8012
3006:8012
3007:8012
3008:8012
4001:8012
4002:8012
4003:8012
4004:8012
4005:8012
5001:8012
5002:8012
1001:8013
1002:8013
1003:8013
1004:8013
1005:8013
1006:8013
1007:8013
1008:8013
1009:8013
1010:8013
1011:8013
1012:8013
1013:8013
1014:8013
2001:8013
2002:8013
2003:8013
2004:8013
2005:8013
2006:8013
2007:8013
2008:8013
2009:8013
2010:8013
3001:8013
3002:8013
3003:8013
3004:8013
3005:8013
3006:8013
3007:8013
3008:8013
4001:8013
4002:8013
4003:8013
4004:8013
4005:8013
5001:8013
5002:8013
1001:8014
1002:8014
1003:8014
1004:8014
1005:8014
1006:8014
1007:8014
1008:8014
1009:8014
1010:8014
1011:8014
1012:8014
1013:8014
1014:8014
2001:8014
2002:8014
2003:8014
2004:8014
2005:8014
2006:8014
2007:8014
2008:8014
2009:8014
2010:8014
3001:8014
3002:8014
3003:8014
3004:8014
3005:8014
3006:8014
3007:8014
3008:8014
4001:8014
4002:8014
4003:8014
4004:8014
4005:8014
5001:8014
5002:8014
1001:8015
1002:8015
1003:8015
1004:8015
1005:8015
1006:8015
1007:8015
1008:8015
1009:8015
1010:8015
1011:8015
1012:8015
1013:8015
1014:8015
2001:8015
2002:8015
2003:8015
2004:8015
2005:8015
2006:8015
2007:8015
2008:8015
2009:8015
2010:8015
3001:8015
3002:8015
3003:8015
3004:8015
3005:8015
3006:8015
3007:8015
3008:8015
4001:8015
4002:8015
4003:8015
4004:8015
4005:8015
5001:8015
5002:8015
1001:8016
1002:8016
1003:8016
1004:8016
1005:8016
1006:8016
1007:8016
1008:8016
1009:8016
1010:8016
1011:8016
1012:8016
1013:8016
1014:8016
2001:8016
2002:8016
2003:8016
2004:8016
2005:8016
2006:8016
2007:8016
2008:8016
2009:8016
2010:8016
3001:8016
3002:8016
3003:8016
3004:8016
3005:8016
3006:8016
3007:8016
3008:8016
4001:8016
4002:8016
4003:8016
4004:8016
4005:8016
5001:8016
5002:8016
—

TABLE B
Example combinations of a compound X with a compound Y.
X:Y
8000:7000
8000:7001
8000:7002
8000:7003
8000:7004
8000:7005
8000:7006
8000:7007
8000:7008
8000:7009
8000:7010
8000:7011
8000:7012
8000:7013
8000:7014
8000:7015
8000:7016
8000:7017
8000:7018
8000:7019
8000:7020
8000:7021
8000:7022
8000:7023
8000:7024
8000:7025
8000:7026
8000:7027
8000:7028
8000:7029
8000:7030
8000:7031
8000:7032
8000:7033
8000:7034
8000:7035
8000:7036
8000:7037
8000:7038
8000:7039
8000:7040
8000:7041
8000:7042
8000:7043
8000:7044
8000:7045
8000:7046
8000:7047
8000:7048
8000:7049
8000:7050
8000:7051
8000:7052
8000:7053
8000:7054
8000:7055
8000:7056
8000:7057
8000:7058
8000:7059
8000:7060
8000:7061
8000:7062
8000:7063
8000:7064
8000:7065
8000:7066
8000:7067
8000:7068
8000:7069
8000:7070
8000:7071
8000:7072
8000:7073
8000:7074
8000:7075
8000:7076
8000:7077
8001:7000
8001:7001
8001:7002
8001:7003
8001:7004
8001:7005
8001:7006
8001:7007
8001:7008
8001:7009
8001:7010
8001:7011
8001:7012
8001:7013
8001:7014
8001:7015
8001:7016
8001:7017
8001:7018
8001:7019
8001:7020
8001:7021
8001:7022
8001:7023
8001:7024
8001:7025
8001:7026
8001:7027
8001:7028
8001:7029
8001:7030
8001:7031
8001:7032
8001:7033
8001:7034
8001:7035
8001:7036
8001:7037
8001:7038
8001:7039
8001:7040
8001:7041
8001:7042
8001:7043
8001:7044
8001:7045
8001:7046
8001:7047
8001:7048
8001:7049
8001:7050
8001:7051
8001:7052
8001:7053
8001:7054
8001:7055
8001:7056
8001:7057
8001:7058
8001:7059
8001:7060
8001:7061
8001:7062
8001:7063
8001:7064
8001:7065
8001:7066
8001:7067
8001:7068
8001:7069
8001:7070
8001:7071
8001:7072
8001:7073
8001:7074
8001:7075
8001:7076
8001:7077
8002:7000
8002:7001
8002:7002
8002:7003
8002:7004
8002:7005
8002:7006
8002:7007
8002:7008
8002:7009
8002:7010
8002:7011
8002:7012
8002:7013
8002:7014
8002:7015
8002:7016
8002:7017
8002:7018
8002:7019
8002:7020
8002:7021
8002:7022
8002:7023
8002:7024
8002:7025
8002:7026
8002:7027
8002:7028
8002:7029
8002:7030
8002:7031
8002:7032
8002:7033
8002:7034
8002:7035
8002:7036
8002:7037
8002:7038
8002:7039
8002:7040
8002:7041
8002:7042
8002:7043
8002:7044
8002:7045
8002:7046
8002:7047
8002:7048
8002:7049
8002:7050
8002:7051
8002:7052
8002:7053
8002:7054
8002:7055
8002:7056
8002:7057
8002:7058
8002:7059
8002:7060
8002:7061
8002:7062
8002:7063
8002:7064
8002:7065
8002:7066
8002:7067
8002:7068
8002:7069
8002:7070
8002:7071
8002:7072
8002:7073
8002:7074
8002:7075
8002:7076
8002:7077
8003:7000
8003:7001
8003:7002
8003:7003
8003:7004
8003:7005
8003:7006
8003:7007
8003:7008
8003:7009
8003:7010
8003:7011
8003:7012
8003:7013
8003:7014
8003:7015
8003:7016
8003:7017
8003:7018
8003:7019
8003:7020
8003:7021
8003:7022
8003:7023
8003:7024
8003:7025
8003:7026
8003:7027
8003:7028
8003:7029
8003:7030
8003:7031
8003:7032
8003:7033
8003:7034
8003:7035
8003:7036
8003:7037
8003:7038
8003:7039
8003:7040
8003:7041
8003:7042
8003:7043
8003:7044
8003:7045
8003:7046
8003:7047
8003:7048
8003:7049
8003:7050
8003:7051
8003:7052
8003:7053
8003:7054
8003:7055
8003:7056
8003:7057
8003:7058
8003:7059
8003:7060
8003:7061
8003:7062
8003:7063
8003:7064
8003:7065
8003:7066
8003:7067
8003:7068
8003:7069
8003:7070
8003:7071
8003:7072
8003:7073
8003:7074
8003:7075
8003:7076
8003:7077
8004:7000
8004:7001
8004:7002
8004:7003
8004:7004
8004:7005
8004:7006
8004:7007
8004:7008
8004:7009
8004:7010
8004:7011
8004:7012
8004:7013
8004:7014
8004:7015
8004:7016
8004:7017
8004:7018
8004:7019
8004:7020
8004:7021
8004:7022
8004:7023
8004:7024
8004:7025
8004:7026
8004:7027
8004:7028
8004:7029
8004:7030
8004:7031
8004:7032
8004:7033
8004:7034
8004:7035
8004:7036
8004:7037
8004:7038
8004:7039
8004:7040
8004:7041
8004:7042
8004:7043
8004:7044
8004:7045
8004:7046
8004:7047
8004:7048
8004:7049
8004:7050
8004:7051
8004:7052
8004:7053
8004:7054
8004:7055
8004:7056
8004:7057
8004:7058
8004:7059
8004:7060
8004:7061
8004:7062
8004:7063
8004:7064
8004:7065
8004:7066
8004:7067
8004:7068
8004:7069
8004:7070
8004:7071
8004:7072
8004:7073
8004:7074
8004:7075
8004:7076
8004:7077
8005:7000
8005:7001
8005:7002
8005:7003
8005:7004
8005:7005
8005:7006
8005:7007
8005:7008
8005:7009
8005:7010
8005:7011
8005:7012
8005:7013
8005:7014
8005:7015
8005:7016
8005:7017
8005:7018
8005:7019
8005:7020
8005:7021
8005:7022
8005:7023
8005:7024
8005:7025
8005:7026
8005:7027
8005:7028
8005:7029
8005:7030
8005:7031
8005:7032
8005:7033
8005:7034
8005:7035
8005:7036
8005:7037
8005:7038
8005:7039
8005:7040
8005:7041
8005:7042
8005:7043
8005:7044
8005:7045
8005:7046
8005:7047
8005:7048
8005:7049
8005:7050
8005:7051
8005:7052
8005:7053
8005:7054
8005:7055
8005:7056
8005:7057
8005:7058
8005:7059
8005:7060
8005:7061
8005:7062
8005:7063
8005:7064
8005:7065
8005:7066
8005:7067
8005:7068
8005:7069
8005:7070
8005:7071
8005:7072
8005:7073
8005:7074
8005:7075
8005:7076
8005:7077
8006:7000
8006:7001
8006:7002
8006:7003
8006:7004
8006:7005
8006:7006
8006:7007
8006:7008
8006:7009
8006:7010
8006:7011
8006:7012
8006:7013
8006:7014
8006:7015
8006:7016
8006:7017
8006:7018
8006:7019
8006:7020
8006:7021
8006:7022
8006:7023
8006:7024
8006:7025
8006:7026
8006:7027
8006:7028
8006:7029
8006:7030
8006:7031
8006:7032
8006:7033
8006:7034
8006:7035
8006:7036
8006:7037
8006:7038
8006:7039
8006:7040
8006:7041
8006:7042
8006:7043
8006:7044
8006:7045
8006:7046
8006:7047
8006:7048
8006:7049
8006:7050
8006:7051
8006:7052
8006:7053
8006:7054
8006:7055
8006:7056
8006:7057
8006:7058
8006:7059
8006:7060
8006:7061
8006:7062
8006:7063
8006:7064
8006:7065
8006:7066
8006:7067
8006:7068
8006:7069
8006:7070
8006:7071
8006:7072
8006:7073
8006:7074
8006:7075
8006:7076
8006:7077
8007:7000
8007:7001
8007:7002
8007:7003
8007:7004
8007:7005
8007:7006
8007:7007
8007:7008
8007:7009
8007:7010
8007:7011
8007:7012
8007:7013
8007:7014
8007:7015
8007:7016
8007:7017
8007:7018
8007:7019
8007:7020
8007:7021
8007:7022
8007:7023
8007:7024
8007:7025
8007:7026
8007:7027
8007:7028
8007:7029
8007:7030
8007:7031
8007:7032
8007:7033
8007:7034
8007:7035
8007:7036
8007:7037
8007:7038
8007:7039
8007:7040
8007:7041
8007:7042
8007:7043
8007:7044
8007:7045
8007:7046
8007:7047
8007:7048
8007:7049
8007:7050
8007:7051
8007:7052
8007:7053
8007:7054
8007:7055
8007:7056
8007:7057
8007:7058
8007:7059
8007:7060
8007:7061
8007:7062
8007:7063
8007:7064
8007:7065
8007:7066
8007:7067
8007:7068
8007:7069
8007:7070
8007:7071
8007:7072
8007:7073
8007:7074
8007:7075
8007:7076
8007:7077
8008:7000
8008:7001
8008:7002
8008:7003
8008:7004
8008:7005
8008:7006
8008:7007
8008:7008
8008:7009
8008:7010
8008:7011
8008:7012
8008:7013
8008:7014
8008:7015
8008:7016
8008:7017
8008:7018
8008:7019
8008:7020
8008:7021
8008:7022
8008:7023
8008:7024
8008:7025
8008:7026
8008:7027
8008:7028
8008:7029
8008:7030
8008:7031
8008:7032
8008:7033
8008:7034
8008:7035
8008:7036
8008:7037
8008:7038
8008:7039
8008:7040
8008:7041
8008:7042
8008:7043
8008:7044
8008:7045
8008:7046
8008:7047
8008:7048
8008:7049
8008:7050
8008:7051
8008:7052
8008:7053
8008:7054
8008:7055
8008:7056
8008:7057
8008:7058
8008:7059
8008:7060
8008:7061
8008:7062
8008:7063
8008:7064
8008:7065
8008:7066
8008:7067
8008:7068
8008:7069
8008:7070
8008:7071
8008:7072
8008:7073
8008:7074
8008:7075
8008:7076
8008:7077
8009:7000
8009:7001
8009:7002
8009:7003
8009:7004
8009:7005
8009:7006
8009:7007
8009:7008
8009:7009
8009:7010
8009:7011
8009:7012
8009:7013
8009:7014
8009:7015
8009:7016
8009:7017
8009:7018
8009:7019
8009:7020
8009:7021
8009:7022
8009:7023
8009:7024
8009:7025
8009:7026
8009:7027
8009:7028
8009:7029
8009:7030
8009:7031
8009:7032
8009:7033
8009:7034
8009:7035
8009:7036
8009:7037
8009:7038
8009:7039
8009:7040
8009:7041
8009:7042
8009:7043
8009:7044
8009:7045
8009:7046
8009:7047
8009:7048
8009:7049
8009:7050
8009:7051
8009:7052
8009:7053
8009:7054
8009:7055
8009:7056
8009:7057
8009:7058
8009:7059
8009:7060
8009:7061
8009:7062
8009:7063
8009:7064
8009:7065
8009:7066
8009:7067
8009:7068
8009:7069
8009:7070
8009:7071
8009:7072
8009:7073
8009:7074
8009:7075
8009:7076
8009:7077
8010:7000
8010:7001
8010:7002
8010:7003
8010:7004
8010:7005
8010:7006
8010:7007
8010:7008
8010:7009
8010:7010
8010:7011
8010:7012
8010:7013
8010:7014
8010:7015
8010:7016
8010:7017
8010:7018
8010:7019
8010:7020
8010:7021
8010:7022
8010:7023
8010:7024
8010:7025
8010:7026
8010:7027
8010:7028
8010:7029
8010:7030
8010:7031
8010:7032
8010:7033
8010:7034
8010:7035
8010:7036
8010:7037
8010:7038
8010:7039
8010:7040
8010:7041
8010:7042
8010:7043
8010:7044
8010:7045
8010:7046
8010:7047
8010:7048
8010:7049
8010:7050
8010:7051
8010:7052
8010:7053
8010:7054
8010:7055
8010:7056
8010:7057
8010:7058
8010:7059
8010:7060
8010:7061
8010:7062
8010:7063
8010:7064
8010:7065
8010:7066
8010:7067
8010:7068
8010:7069
8010:7070
8010:7071
8010:7072
8010:7073
8010:7074
8010:7075
8010:7076
8010:7077
8011:7000
8011:7001
8011:7002
8011:7003
8011:7004
8011:7005
8011:7006
8011:7007
8011:7008
8011:7009
8011:7010
8011:7011
8011:7012
8011:7013
8011:7014
8011:7015
8011:7016
8011:7017
8011:7018
8011:7019
8011:7020
8011:7021
8011:7022
8011:7023
8011:7024
8011:7025
8011:7026
8011:7027
8011:7028
8011:7029
8011:7030
8011:7031
8011:7032
8011:7033
8011:7034
8011:7035
8011:7036
8011:7037
8011:7038
8011:7039
8011:7040
8011:7041
8011:7042
8011:7043
8011:7044
8011:7045
8011:7046
8011:7047
8011:7048
8011:7049
8011:7050
8011:7051
8011:7052
8011:7053
8011:7054
8011:7055
8011:7056
8011:7057
8011:7058
8011:7059
8011:7060
8011:7061
8011:7062
8011:7063
8011:7064
8011:7065
8011:7066
8011:7067
8011:7068
8011:7069
8011:7070
8011:7071
8011:7072
8011:7073
8011:7074
8011:7075
8011:7076
8011:7077
8012:7000
8012:7001
8012:7002
8012:7003
8012:7004
8012:7005
8012:7006
8012:7007
8012:7008
8012:7009
8012:7010
8012:7011
8012:7012
8012:7013
8012:7014
8012:7015
8012:7016
8012:7017
8012:7018
8012:7019
8012:7020
8012:7021
8012:7022
8012:7023
8012:7024
8012:7025
8012:7026
8012:7027
8012:7028
8012:7029
8012:7030
8012:7031
8012:7032
8012:7033
8012:7034
8012:7035
8012:7036
8012:7037
8012:7038
8012:7039
8012:7040
8012:7041
8012:7042
8012:7043
8012:7044
8012:7045
8012:7046
8012:7047
8012:7048
8012:7049
8012:7050
8012:7051
8012:7052
8012:7053
8012:7054
8012:7055
8012:7056
8012:7057
8012:7058
8012:7059
8012:7060
8012:7061
8012:7062
8012:7063
8012:7064
8012:7065
8012:7066
8012:7067
8012:7068
8012:7069
8012:7070
8012:7071
8012:7072
8012:7073
8012:7074
8012:7075
8012:7076
8012:7077
8013:7000
8013:7001
8013:7002
8013:7003
8013:7004
8013:7005
8013:7006
8013:7007
8013:7008
8013:7009
8013:7010
8013:7011
8013:7012
8013:7013
8013:7014
8013:7015
8013:7016
8013:7017
8013:7018
8013:7019
8013:7020
8013:7021
8013:7022
8013:7023
8013:7024
8013:7025
8013:7026
8013:7027
8013:7028
8013:7029
8013:7030
8013:7031
8013:7032
8013:7033
8013:7034
8013:7035
8013:7036
8013:7037
8013:7038
8013:7039
8013:7040
8013:7041
8013:7042
8013:7043
8013:7044
8013:7045
8013:7046
8013:7047
8013:7048
8013:7049
8013:7050
8013:7051
8013:7052
8013:7053
8013:7054
8013:7055
8013:7056
8013:7057
8013:7058
8013:7059
8013:7060
8013:7061
8013:7062
8013:7063
8013:7064
8013:7065
8013:7066
8013:7067
8013:7068
8013:7069
8013:7070
8013:7071
8013:7072
8013:7073
8013:7074
8013:7075
8013:7076
8013:7077
8014:7000
8014:7001
8014:7002
8014:7003
8014:7004
8014:7005
8014:7006
8014:7007
8014:7008
8014:7009
8014:7010
8014:7011
8014:7012
8014:7013
8014:7014
8014:7015
8014:7016
8014:7017
8014:7018
8014:7019
8014:7020
8014:7021
8014:7022
8014:7023
8014:7024
8014:7025
8014:7026
8014:7027
8014:7028
8014:7029
8014:7030
8014:7031
8014:7032
8014:7033
8014:7034
8014:7035
8014:7036
8014:7037
8014:7038
8014:7039
8014:7040
8014:7041
8014:7042
8014:7043
8014:7044
8014:7045
8014:7046
8014:7047
8014:7048
8014:7049
8014:7050
8014:7051
8014:7052
8014:7053
8014:7054
8014:7055
8014:7056
8014:7057
8014:7058
8014:7059
8014:7060
8014:7061
8014:7062
8014:7063
8014:7064
8014:7065
8014:7066
8014:7067
8014:7068
8014:7069
8014:7070
8014:7071
8014:7072
8014:7073
8014:7074
8014:7075
8014:7076
8014:7077
8015:7000
8015:7001
8015:7002
8015:7003
8015:7004
8015:7005
8015:7006
8015:7007
8015:7008
8015:7009
8015:7010
8015:7011
8015:7012
8015:7013
8015:7014
8015:7015
8015:7016
8015:7017
8015:7018
8015:7019
8015:7020
8015:7021
8015:7022
8015:7023
8015:7024
8015:7025
8015:7026
8015:7027
8015:7028
8015:7029
8015:7030
8015:7031
8015:7032
8015:7033
8015:7034
8015:7035
8015:7036
8015:7037
8015:7038
8015:7039
8015:7040
8015:7041
8015:7042
8015:7043
8015:7044
8015:7045
8015:7046
8015:7047
8015:7048
8015:7049
8015:7050
8015:7051
8015:7052
8015:7053
8015:7054
8015:7055
8015:7056
8015:7057
8015:7058
8015:7059
8015:7060
8015:7061
8015:7062
8015:7063
8015:7064
8015:7065
8015:7066
8015:7067
8015:7068
8015:7069
8015:7070
8015:7071
8015:7072
8015:7073
8015:7074
8015:7075
8015:7076
8015:7077
8016:7000
8016:7001
8016:7002
8016:7003
8016:7004
8016:7005
8016:7006
8016:7007
8016:7008
8016:7009
8016:7010
8016:7011
8016:7012
8016:7013
8016:7014
8016:7015
8016:7016
8016:7017
8016:7018
8016:7019
8016:7020
8016:7021
8016:7022
8016:7023
8016:7024
8016:7025
8016:7026
8016:7027
8016:7028
8016:7029
8016:7030
8016:7031
8016:7032
8016:7033
8016:7034
8016:7035
8016:7036
8016:7037
8016:7038
8016:7039
8016:7040
8016:7041
8016:7042
8016:7043
8016:7044
8016:7045
8016:7046
8016:7047
8016:7048
8016:7049
8016:7050
8016:7051
8016:7052
8016:7053
8016:7054
8016:7055
8016:7056
8016:7057
8016:7058
8016:7059
8016:7060
8016:7061
8016:7062
8016:7063
8016:7064
8016:7065
8016:7066
8016:7067
8016:7068
8016:7069
8016:7070
8016:7071
8016:7072
8016:7073
8016:7074
8016:7075
8016:7076
8016:7077
—
—

TABLE C
Example combinations of a compound X with a compound Y.
X:Y
6000:8000
6001:8000
6002:8000
6003:8000
6004:8000
6005:8000
6006:8000
6007:8000
6008:8000
6009:8000
6010:8000
6011:8000
6012:8000
6013:8000
6014:8000
6015:8000
6016:8000
6017:8000
6018:8000
6019:8000
6020:8000
6021:8000
6022:8000
6023:8000
6024:8000
6025:8000
6026:8000
6027:8000
6028:8000
6029:8000
6030:8000
6031:8000
6032:8000
6033:8000
6034:8000
6035:8000
6036:8000
6037:8000
6038:8000
6039:8000
6040:8000
6041:8000
6042:8000
6043:8000
6044:8000
6045:8000
6046:8000
6047:8000
6048:8000
6049:8000
6050:8000
6051:8000
6052:8000
6053:8000
6054:8000
6055:8000
6056:8000
6057:8000
6058:8000
6059:8000
6060:8000
6061:8000
6062:8000
6063:8000
6064:8000
6065:8000
6066:8000
6067:8000
6068:8000
6069:8000
6070:8000
6071:8000
6072:8000
6073:8000
6074:8000
6075:8000
6076:8000
6077:8000
6078:8000
6000:8001
6001:8001
6002:8001
6003:8001
6004:8001
6005:8001
6006:8001
6007:8001
6008:8001
6009:8001
6010:8001
6011:8001
6012:8001
6013:8001
6014:8001
6015:8001
6016:8001
6017:8001
6018:8001
6019:8001
6020:8001
6021:8001
6022:8001
6023:8001
6024:8001
6025:8001
6026:8001
6027:8001
6028:8001
6029:8001
6030:8001
6031:8001
6032:8001
6033:8001
6034:8001
6035:8001
6036:8001
6037:8001
6038:8001
6039:8001
6040:8001
6041:8001
6042:8001
6043:8001
6044:8001
6045:8001
6046:8001
6047:8001
6048:8001
6049:8001
6050:8001
6051:8001
6052:8001
6053:8001
6054:8001
6055:8001
6056:8001
6057:8001
6058:8001
6059:8001
6060:8001
6061:8001
6062:8001
6063:8001
6064:8001
6065:8001
6066:8001
6067:8001
6068:8001
6069:8001
6070:8001
6071:8001
6072:8001
6073:8001
6074:8001
6075:8001
6076:8001
6077:8001
6078:8001
6000:8002
6001:8002
6002:8002
6003:8002
6004:8002
6005:8002
6006:8002
6007:8002
6008:8002
6009:8002
6010:8002
6011:8002
6012:8002
6013:8002
6014:8002
6015:8002
6016:8002
6017:8002
6018:8002
6019:8002
6020:8002
6021:8002
6022:8002
6023:8002
6024:8002
6025:8002
6026:8002
6027:8002
6028:8002
6029:8002
6030:8002
6031:8002
6032:8002
6033:8002
6034:8002
6035:8002
6036:8002
6037:8002
6038:8002
6039:8002
6040:8002
6041:8002
6042:8002
6043:8002
6044:8002
6045:8002
6046:8002
6047:8002
6048:8002
6049:8002
6050:8002
6051:8002
6052:8002
6053:8002
6054:8002
6055:8002
6056:8002
6057:8002
6058:8002
6059:8002
6060:8002
6061:8002
6062:8002
6063:8002
6064:8002
6065:8002
6066:8002
6067:8002
6068:8002
6069:8002
6070:8002
6071:8002
6072:8002
6073:8002
6074:8002
6075:8002
6076:8002
6077:8002
6078:8002
6000:8003
6001:8003
6002:8003
6003:8003
6004:8003
6005:8003
6006:8003
6007:8003
6008:8003
6009:8003
6010:8003
6011:8003
6012:8003
6013:8003
6014:8003
6015:8003
6016:8003
6017:8003
6018:8003
6019:8003
6020:8003
6021:8003
6022:8003
6023:8003
6024:8003
6025:8003
6026:8003
6027:8003
6028:8003
6029:8003
6030:8003
6031:8003
6032:8003
6033:8003
6034:8003
6035:8003
6036:8003
6037:8003
6038:8003
6039:8003
6040:8003
6041:8003
6042:8003
6043:8003
6044:8003
6045:8003
6046:8003
6047:8003
6048:8003
6049:8003
6050:8003
6051:8003
6052:8003
6053:8003
6054:8003
6055:8003
6056:8003
6057:8003
6058:8003
6059:8003
6060:8003
6061:8003
6062:8003
6063:8003
6064:8003
6065:8003
6066:8003
6067:8003
6068:8003
6069:8003
6070:8003
6071:8003
6072:8003
6073:8003
6074:8003
6075:8003
6076:8003
6077:8003
6078:8003
6000:8004
6001:8004
6002:8004
6003:8004
6004:8004
6005:8004
6006:8004
6007:8004
6008:8004
6009:8004
6010:8004
6011:8004
6012:8004
6013:8004
6014:8004
6015:8004
6016:8004
6017:8004
6018:8004
6019:8004
6020:8004
6021:8004
6022:8004
6023:8004
6024:8004
6025:8004
6026:8004
6027:8004
6028:8004
6029:8004
6030:8004
6031:8004
6032:8004
6033:8004
6034:8004
6035:8004
6036:8004
6037:8004
6038:8004
6039:8004
6040:8004
6041:8004
6042:8004
6043:8004
6044:8004
6045:8004
6046:8004
6047:8004
6048:8004
6049:8004
6050:8004
6051:8004
6052:8004
6053:8004
6054:8004
6055:8004
6056:8004
6057:8004
6058:8004
6059:8004
6060:8004
6061:8004
6062:8004
6063:8004
6064:8004
6065:8004
6066:8004
6067:8004
6068:8004
6069:8004
6070:8004
6071:8004
6072:8004
6073:8004
6074:8004
6075:8004
6076:8004
6077:8004
6078:8004
6000:8005
6001:8005
6002:8005
6003:8005
6004:8005
6005:8005
6006:8005
6007:8005
6008:8005
6009:8005
6010:8005
6011:8005
6012:8005
6013:8005
6014:8005
6015:8005
6016:8005
6017:8005
6018:8005
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