Cyclitolamines

U.S. Pat. No. 3,894,031, issued July 8, 1975, discloses, inter alia, that compounds having the formula ##STR3## wherein R' and R" are the same or different and can be hydrogen, alkyl, haloalkyl, cycloalkyl, cycloalkyl-alkyl, aryl, arylalkyl, or heterocyclic, or the group --NR'R" can be a heterocyclic group, are useful for the treatment of hypertension.

U.S. Pat. No. 3,971,823, issued on July 23, 1976, discloses that compounds having the structure ##STR4## wherein R.sub.1 is alkyl or arylalkyl, are useful for the treatment of hypertension.

Compounds having the formula ##STR5## and the pharmaceutically acceptable acid-addition salts thereof, are useful for the treatment of hypertension. In formula I, and throughout the specification, the symbols are as defined below.

R.sub.1 is alkyl or arylalkyl;

R.sub.2 is --C.tbd.N, --C.tbd.CH or ##STR6## wherein R.sub.4 is hydrogen, alkyl, aryl, or arylalkyl;

R.sub.3 is alkanoyl;

M IS 1, 2, 3, OR 4;

N IS 1, 2, OR 3; AND P IS 0, 1, 2, OR 3.

The term "aryl", as used throughout the specification, refers to phenyl or phenyl substituted with one or two halogen, alkyl or alkoxy groups.

The terms "alkyl" and "alkoxy", as used throughout the specification, refer to groups having 1 to 6 carbon atoms.

The term "alkanoyl", as used throughout the specification, refers to groups having the formula ##STR7## wherein Y is alkyl as defined above.

The products of formula I can be prepared from compounds having the structure ##STR8## The compounds of formula II are known; see, for example, U.S. Pat. No. 3,894,031 issued July 8, 1975.

Reaction of a compound of formula II with a compound having the formula

wherein X is chlorine or bromine, yields the corresponding compound of formula I. The reaction can be run in an organic solvent, e.g., benzene, in the presence of an organic base, e.g., triethylamine. Reaction conditions are not critical, but the reaction will most preferably be run at room temperature.

Those compounds of formula I, wherein p is 2 and R.sub.2 is --C.tbd.N, are most conveniently prepared by reacting a compound of formula II with acrylonitrile. The reaction is preferably run under reflux conditions.

The compounds of formula I can be converted to their pharmaceutically acceptable acid-addition salts using methods well known in the art. Exemplary salts are hydrohalides (e.g., hydrochloride and hydrobromide), nitrate, phosphate, borate, acetate, tartrate, methanesulfonate, benzenesulfonate, toluenesulfonate and the like.

The compounds of formula I, and the pharmaceutically acceptable acid-addition salts thereof, inhibit the conversion of angiotensin I to angiotensin II. They are useful as hypotensive agents in mammals, e.g., domestic animals such as dogs, cats, etc. Daily doses of from 5 to 50 mg/kg of animal body weight, preferably about 5 to 25 mg/kg of animal body weight can be administered in single or divided doses.

The active compounds of the present invention are administered orally, for example, with an inert diluent or with an assimilable edible carrier, or they may be enclosed in hard or soft gelatin capsules, or they may be compressed into tablets, or they may be incorporated directly with the food of the diet. For oral therapeutic administration, the active compounds of this invention may be incorporated with excipients and used in the form of tablets, troches, capsules, elixirs, suspensions, syrups, wafers, chewing gum, and the like. Such compositions and preparations should contain at least 0.1% of active compound. The percentage in the compositions and preparations may, of course, be varied and may conveniently be between about 5% to about 75% or more of the weight of the unit. The amount of active compound in such therapeutically useful compositions or preparations is such that a suitable dosage will be obtained. Preferred compositions or preparations according to the present invention are prepared so that an oral dosage unit form contains between about 5 and 250 milligrams of active compound.

Compounds having the structure ##STR9## are specifically contemplated. Compounds of formulas IV, V and VI wherein R.sub.3 is acetyl are preferred.

The following examples are specific embodiments of this invention.

3a,7a-trans-5,6-trans-Hexahydro-1-[3-(methylamino)- propyl]-3a,5,6,7a-indantetrol, tetraacetate ester (10.0 g.), triethylamine (2.6 g) and allyl bromide (3.0 g) are dissolved in 100 ml benzene and stirred at room temperature for 3 hours. The solid (6.6 g) is removed by filtration; indicating this is largely the hydobromide of the starting tetraacetate. The filtrate is washed twice with water, dried, and the solvent is removed in vacuo leaving 5.45 g of crystalline material. This is recrystallized once from benzene-hexane and once from ether-hexane to give 2.85 g of the title compound, melting point 106.degree.-108.5.degree. C.

3a,7a-trans-5,6-trans-Hexahydro-1-[3-(methylamino)propyl]3a,5,6,7a-indantet rol, tetraacetate ester (8.54 g) and cinnamyl bromide (2.2 g) are dissolved in benzene (100 ml) and stirred for about 16 hours at room temperature. The crystalline hydrobromide (4.3 g) of the starting material is removed by filtration. The filtrate is washed twice with water. The benzene solution is dried, filtered and the solvent is removed in vacuo leaving 6.0 g of viscous material. Attempts to crystallize this material are not successful. The material is dissolved in ether and a solution of hydrogen chloride in isopropanol is added. The gummy hydrochloride is washed several times with ether, dissolved in water and the solution is extracted twice with ether. The aqueous layer is then basified with concentrated ammonium hydroxide and the free base is extracted into ether. After drying and removal of solvent 4.26 of foam remains. Two crystallizations from ether give 1.05 g of the title compound, melting point 96.degree.-105.degree. C.

3a,7a-trans-5,6-trans-Hexahydro-1-[3-(methylamino)propyl]3a,5,6,7a-indantet rol, tetraacetate ester

3a,7a-trans-5,6,-trans-Hexahydro-1-[3-(methylamino)propyl]-3a,5,6,7a-indant etrol, tetracetate ester (10.0 g), triethylamine (3.0 g) and propargyl bromide (3.0 g) are dissolved in 100 ml of benzene and the mixture is stirred for about 16 hours at room temperature. The resulting precipitate is removed by filtration. The filtrate is washed twice with water, dried, and the solvent is removed in vacuo leaving 6.85 g of partially crystalline material. This is recrystallized from ether-hexane to yield 4.85 g of the title compound, melting point 112.degree.-120.degree. C.

A mixture of 3a,7a-trans-5,6-trans-Hexahydro-1-[3(methylamino)propyl]-3a,5,6,7a-indante trol, tetraacetate ester (8.54 g) and acrylonitrile (50 ml) is heated under reflux conditions for about 16 hours in a nitrogen atmosphere. After cooling, ether is added and a small amount of insoluble material is removed by filtration. The solvent is removed in vacuo leaving 9.9 g of viscous material. Crystallization from ether gives a first crop of 3.79 g. This is recrystallized from ether-ethyl acetate to give 2.43 g of the title compound, melting point 95.degree.-116.degree. C.

Following the procedure of Example 3, but substituting the compound listed in column I for 3a,7a-trans-5,6-trans-hexahydro-1-[3-(methylamino)propyl]-3a,5,6,7a-indant etrol, tetraacetate ester and the compound listed in column II for allyl bromide, yields the compound listed in column III.

Following the procedure of example 3, but substituting the compound listed in column I for 3a,7a-trans-5,6-trans-hexahydro-1-[3-(methylamino)propyl]-3a,5,6,7a-indant etrol, tetra-acetate ester and the compound listed in column II for propargyl bromide, yields the compound listed in column III.

Following the procedure of example 4, but substituting the compound listed in column I for 3a,7a-trans-5,6-trans-hexahydro-1- [3-(methylamino)propyl]-3a,5,6,7a-indantetrol, tetraacetate ester, yields the compound listed in column II.