US 4,041,232 AGrant
Amphotericin B Methyl Ester Salts
Issue Date:1977-08-09
•10 Claims
Abstract
Amphotericin B methyl ester salts, such as salts formed by reaction with mono and dicarboxylic amino acids (such as aspartic acid, or glutamic acid or pyroglutamic acid), hydroxy carboxylic acids (such as lactic acid) and mono and dicarboxylic acids (such as acetic acid) are provided and have been found to be readily water-soluble and at least as stable and active as the parent ester compound.
Metadata
Assignee
- E. R. Squibb & Sons, Inc.
Inventors
- Frank Sipos
- Adam J. Keseleski
Application Information
Application Number:US 6605982
Filing Date:1976-02-23
Priority Date:1976-02-23
Art Unit:124
Classifications
IPC:
C07H 1708
Field of Search:
53617;4
Patent Drawings
This patent does not have any drawings.
Description
The present invention relates to water-soluble salts of the methyl ester of amphotericin B.
The methyl ester of amphotericin B which has the formula ##STR1## has been prepared by mixing amphotericin B starting material with dimethylsulfoxide and methanol to form a solution of the amphotericin B. The dissolved amphotericin B is then esterified by reaction with diazomethane and the resulting reaction mixture treated with ethyl ether to precipitate the methyl ester.
While the methyl ester of amphotericin B is particularly valuable for its antifungal properties and in the apparent inability of fungus organisms to develop strains or forms that are resistant to amphotericin B methyl ester, its use has been limited by lack of adequate water solubility.
The present invention provides new more soluble forms of the methyl ester of amphotericin B which are salts thereof formed by reaction with monocarboxylic amino acids, dicarboxylic amino acids, hydroxy acids, hydrocarbon monocarboxylic acids and hydrocarbon polycarboxylic acids.
The mono and dicarboxylic amino acids (natural or synthetic) which are suitable for use herein include alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, sarcosine, serine, threonine, tryptophan, tyrosine and valine and all optical isomers and derivatives thereof, with glutamic acid, aspartic acid and pyroglutamic acid being preferred.
The hydroxy acids suitable for use herein may contain one or two hydroxy groups and up to 12 carbons, and include, but are not limited to, glycolic acid, lactic acid, hydroxybutyric acid, malic acid, and tartaric acid, including isomers thereof, with lactic acid being preferred.
The hydrocarbon mono and dicarboxylic acid may contain one, two or three carboxyl groups and (up to 15 carbons and) include alkanoic acids, alkenoic acids or aromatic acids. Such acids suitable for use herein include, but are not limited to, formic acid, acetic acid, butyric acid, valeric acid, caproic acid, caprylic acid, capric acid, octanoic acid, palmitic acid, stearic acid, glutaric acid, adipic acid, malonic acid, succinic acid, oxalic acid, crotonic acid, oleic acid, acrylic acid, vinylacetic acid, maleic acid, fumaric acid, benzoic acid, phenylacetic acid, hydrocinnamic acid, cinnamic acid, mellitic acid, o- or p-toluic acid, phthalic acid, terephthalic acid or naphthoic acids, with acetic acid being preferred.
Preferred salts of the amphotericin B methyl ester in accordance with the present invention include the glutamic acid salt, pyroglutamic acid salt, aspartic acid salt, and the acetic acid salt.
In general, aqueous solutions containing from 0.1 to 10% by weight of the salts of the invention will have a pH within the range of from about 5 to about 6.5 and preferably from about 6 to about 6.4.
The salts of the invention are readily water soluble, that is, have a solubility of 10% or more, and are as stable as and may be more stable than, and as active as the methyl ester of amphotericin B.
The salts of the invention may be easily prepared by simply adding portions of the amphotericin B methyl ester to an aqueous solution or suspension of the particular acid (0.2 to 2% by weight acid) to be employed. Where the acid is a mono carboxylic acid, it is preferred that 1:1 molar ratios of the acid and ester be employed. However, where dicarboxylic acids are employed, it is preferred that a weight ratio of acid:ester of within the range of from about 1:1 to about 1:2 and more preferably 1:2 be employed.
The salts of the invention retain the antifungal activity of amphotericin B methyl ester, are stable in the dry form as well as in solution, and are readily soluble in water so as to permit the preparation of concentrated aqueous solutions in the range of from about 2 g to 12 g per liter. Such concentrated aqueous solutions may be used, for example, to control fungal growths in the digestive tract of fowl by supplying it to the drinking water.
The following Examples represent preferred embodiments of the present invention.
EXAMPLE 1
Amphotericin B Methyl Ester-L-Glutamate ##STR2##
Amphotericin B methyl ester (9.36 g 0.01 Mol) is added in portions to a suspension of the L-glutamic acid (1.47 g 0.01 Mole) in 300 ml of water and the mixture is stirred until complete dissolution. The clear solution is thereafter freeze dried. The yield is quantitative. The product has a solubility in water of about 10% or more at RT.
EXAMPLE 2
Amphotericin B Methyl Ester-Pyroglutamate ##STR3##
Amphotericin B methyl ester (9.36 g, 0.01 Mol) is added in portions to a solution of pyroglutamic acid (1.30 g, 0.01 Mol) in 500 ml of water and stirred until dissolution (5-10 minutes). The clear solution is thereafter lyopholized. The resulting product is found to be very soluble in water (more than 10% soluble at RT).
EXAMPLE 3
Amphotericin B Methyl Ester-L-Glutamate ##STR4##
Amphotericin B methyl ester (9.36 g, 0.01 Mol) is added in portions to a solution of L-glutamic acid (0.81 g, 0.0055 Mol) in 500 ml of water and stirred until complete dissolution (1 hour). The clear solution is then lyopholized. The yield is 88.9%. The product is soluble in water even at concentrations of 10% at RT and when dissolved in water to form a 1% solution is found to have a pH of 6.02.
EXAMPLE 4
Amphotericin B Methyl Ester-L-Aspartate ##STR5##
Amphotericin B methyl ester (9.36 g, 0.01 Mol) is added in portions to a solution of L-aspartic acid (0.73 g, 0.0055 Mol) in 500 ml of water and stirred until dissolution (1 hour). The clear solution is thereafter freeze-dried. The product when dissolved in water (1%) has a pH of 6.25 and a solubility of greater than 10% at RT.
EXAMPLE 5
Amphotericin B Methyl Ester-L-Aspartate ##STR6##
Amphotericin B methyl ester (9.36 g, 0.01 Mol) is added in portions to a solution of L-aspartic acid (1.33 g, 0.01 Mol) in 500 ml of water and stirred until complete dissolution. The clear solution is then lyopholized. The product has a solubility of more than 10% water at RT.
EXAMPLE 6
Amphotericin B Methyl Ester Acetate ##STR7##
Amphotericin B methyl ester (9.36 g, 0.01 Mol) is added in portions to a solution of acetic acid (0.60 g, 0.01 Mol) in 500 ml of water and stirred until complete dissolution. The clear solution is then lyopholized. The product when dissolved in water (1%) has a pH of 6.4 and a solubility greater than 10% at R.T.
EXAMPLE 7
Amphotericin B Methyl Ester Propionate
Amphotericin B methyl ester is added in portions to a solution of propionic acid in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 8
Amphotericin B Methyl Ester Octanoate
Amphotericin B methyl ester is added in portions to a solution of octanoic acid in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 9
Amphotericin B Methyl Ester Laurate
Amphotericin B methyl ester is added in portions to a solution of lauric acid in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 10
Amphotericin B Methyl Ester Formate
Amphotericin B methyl ester is added in portions to a solution of formic acid in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 11
Amphotericin B Methyl Ester Lactate
Amphotericin B methyl ester is added in portions to a solution of lactic acid in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 12
Amphotericin B Methyl Ester Alaninate
Amphotericin B methyl ester is added in portions to a solution of alanine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 13
Amphotericin B Methyl Ester Carbamate
Amphotericin B methyl ester is added in portions to a solution of carbamic acid in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 14
Amphotericin B Methyl Ester Glycinate
Amphotericin B methyl ester is added in portions to a solution of glycine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 15
Amphotericin B Methyl Ester Sarcosinate
Amphotericin B methyl ester is added in portions to a solution of sarcosine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 16
Amphotericin B Methyl Ester Valinate
Amphotericin B methyl ester is added in portions to a solution of valine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 17
Amphotericin B Methyl Ester Leucinate
Amphotericin B methyl ester is added in portions to a solution of leucine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 18
Amphotericin B Methyl Ester Isovalinate
Amphotericin B methyl ester is added in portions to a solution of isovaline in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 19
Amphotericin B Methyl Ester Phenylalaninate
Amphotericin B methyl ester is added in portions to a solution of phenylalanine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 20
Amphotericin B Methyl ESter Serinate
Amphotericin B methyl ester is added in portions to a solution of serine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 21
Amphotericin B Methyl Ester Cysteinate
Amphotericin B methyl ester is added in portions to a solution of cysteine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 22
Amphotericin B Methyl Ester Methioninate
Amphotericin B methyl ester is added in portions to a solution of methionine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 23
Amphotericin B Methyl Ester Lysinate
Amphotericin B methyl ester is added in portions to a solution of lysine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 24
Amphotericin B Methyl Ester Ornithinate
Amphotericin B methyl ester is added in portions to a solution of ornithine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 25
Amphotericin B Methyl Ester Asparaginate
Amphotericin B methyl ester is added in portions to a solution of asparagine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 26
Amphotericin B Methyl Ester Histidinate
Amphotericin B methyl ester in added in portions to a solution of histidine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 27
Amphotericin B Methyl Ester Tryptophanate
Amphotericin B methyl ester is added in portions to a solution of tryptophan in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 28
Amphotericin B Methyl Ester Prolinate
Amphotericin B methy ester is added in portions to a solution of proline in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 29
Amphotericin B Methyl Ester Hydroxyprolinate
Amphotericin B methyl ester is added in portions to a solution of hydroxyproline in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 30
Amphotericin B Methyl Ester Threoninate
Amphotericin B methyl ester is added in portions to a solution of threonine 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 31
Amphotericin B Methyl Ester Isoleucinate
Amphotericin B methyl ester is added in portions to a solution of isoleucine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 32
Amphotericin B Methyl Ester Norleucinate
Amphotericin B methyl ester is added in portions to a solution of norleucine in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 33
Amphotericin B Methyl Ester Norvalinate
Amphotericin B methyl ester is added in portions to a solution of norvaline in 1:1 molar ratio of water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 34
Amphotericin B Methyl Ester Tartrate
Amphotericin B methyl ester is added in portions to a solution of tartaric acid in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 35
Amphotericin B Methyl Ester Valerate
Amphotericin B methyl ester is added in portions to a solution of valeric acid in 1:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 36
Amphotericin B Methyl Ester Glutarate
Amphotericin B methyl ester is added in portions to a solution of glutaric acid in 2:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 37
Amphotericin B Methyl Ester Adipate
Amphotericin B methyl ester is added in portions to a solution of adipic acid in 2:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 38
Amphotericin B Methyl Ester Malonate
Amphotericin B methyl ester is added in portions to a solution of malonic acid in 2:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 39
Amphotericin B Methyl Ester Succinate
Amphotericin B methyl ester is added in portions to a solution of succinic acid in 2:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
EXAMPLE 40
Amphotericin B Methyl Ester Oxalate
Amphotericin B methyl ester is added in portions to a solution of oxalic acid in 2:1 molar ratio in water and stirred until dissolution. The clear solution is then lyopholized.
Claims
What is claimed is:
1. A salt of the methyl ester of amphotericin B, said salt being selected from mono and dicarboxylic amino acid salts of the methyl ester of amphotericin B.
2. The salt as defined in claim 1 wherein said salt is a salt of a monocarboxylic amino acid.
3. The salt as defined in claim 2 wherein said monocarboxylic amino acid is selected from the group consisting of carbamic acid, glycine, glycin, alanine, valine, leucine, isovaline, phenylalanine, tyrosine, sarcosine, serine, cysteine, methionine, norvaline, norleucine, isoleucine, threonine, thyroxine, arginine, lysine, ornithine, asparagine, citrulline, histidine, tryptophan, proline and hydroxyproline.
4. The salt as defined in claim 3 wherein said amino acid is pyroglutamic acid.
5. The salt as defined in claim 1 wherein said salt is a salt of a dicarboxylic amino acid.
6. The salt as defined in claim 5 wherein said amino acid is selected from the group consisting of glutamic acid and aspartic acid.
7. The salt as defined in claim 1 having the name amphotericin B methyl ester glutamate.
8. The salt as defined in claim 1 having the name amphotericin B methyl ester aspartate.
9. The salt as defined in claim 1 having the name amphotericin B methyl ester pyroglutamate.
10. The salt as defined in claim 1 having a pH when dissolved in water at 1% concentration ranging from about 5 to about 6.5.
Patent Citations (1)
| Patent | Date | Inventor | Cited By |
|---|---|---|---|
| US3945993 | 1976-03-01 | Schaffner et al. |