CS228118B2 - Production of mercaptoacylderivatives of substitutes prolines - Google Patents

Abstract

New mercaptoacyl derivatives of substituted prolines which have the general formula <IMAGE> or salts thereof may be used as hypotensive agents. In the formula X-R1 group is located at the 3- or 4- position of the proline ring; X is oxygen or sulfur; R is hydrogen or lower alkyl; R1 is lower alkyl, lower alkenyl, lower alkynyl, phenyl, substituted phenyl, phenyl-lower alkylene, or substituted phenyl-lower alkylene; R2 and R3 are independently selected from hydrogen, lower alkyl and trifluoromethyl; R4 is hydrogen, <IMAGE> or <IMAGE> R5 is lower alkyl, phenyl, or phenyl-lower alkylene; and n is 0, 1 or 2.

Description

The present invention relates to a process for the preparation of the novel mercaptoacylproline ethers and thioethers of general formula (I)

wherein the X-R 1 group is attached at the 3 or 4 position of the proline ring,

X represents oxygen or sulfur,

R represents a hydrogen atom or a (C1-C4) alkyl group,

R 1 represents a C 1 -C 4 alkyl or phenyl group optionally substituted by a halogen atom, a methyl group or a methoxy group,

R2 represents a hydrogen atom or an alkyl group having 1 to 7 carbon atoms;

R a represents a hydrogen atom, a C 1 -C 4 alkanoyl group or a benzoyl group and their base salts.

Examples of the above-mentioned alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl and tert-butyl, with methyl and ethyl being the most preferred groups of this type.

The term "halogen atom" includes four conventional members of this group, i.e., chlorine, bromine, fluorine and iodine atoms, with chlorine, bromine and fluorine being preferred halogens.

The compounds of formula I contain an asymmetric center on the carbon atom at the 2-position of the proline ring.

Of course, an additional center of asymmetry may be present in the mercapto-containing side chain, depending on the R 2 substituent. Accordingly, the products of formula I may exist in stereoisomeric forms or in racemic mixtures thereof. All such forms are within the scope of the invention. In the synthesis described below, the racemate or one of the enantiomers may be used as starting material. When a racemic starting material is used in the synthesis, the stereoisomers contained in the resulting product can be separated by conventional chromatography or traction crystallization. Cis-trans isomerism may also occur due to the presence of the X-R1 moiety.

Preferably, the center of asymmetry is in pro228118

The 220-line ring in the L-configuration and if there is an asymmetric center in the mercaptoacyl side chain, this additional asymmetric center is preferably in the D-configuration.

Preferred compounds are those compounds of formula (I) wherein:

R is hydrogen,

R 1 represents an alkyl group having 1 to carbon atoms or a phenyl group optionally substituted by a methyl group, a methoxy group, a chlorine or fluorine atom,

R2 is hydrogen or methyl or trifluoromethyl and

R 1 represents a hydrogen atom.

Also preferred as intermediates are the above compounds in which R a represents an acetyl or benzoyl group, in particular an acetyl group.

Most preferred are those compounds of formula I above

X is an oxygen atom,

R 1 represents a methyl or ethyl group, in particular a methyl group,

R2 represents a hydrogen atom or a methyl group, in particular a methyl group,

R4 represents a hydrogen atom and the —XR1 group is attached at the 4-position of the proline ring, and especially those compounds in which the —XR1 group is in the cis configuration.

In accordance with the invention, the compounds of formula (I) and their base salts are prepared by producing a proline derivative of formula (II) wherein:

R, R 1 and X are as defined above, condensed with an acid of formula III

R2

R1‘ — S — CH2 — CH — COOH (ΠΙ) in which

R 2 is as defined above and

R 1 'represents a C 1 -C 10 alkanoyl or benzoyl group, the resulting product in which R d represents a C 1 -C 4 alkanoyl or benzoyl group is optionally hydrolyzed to the corresponding hydrogen compound R 4 and the resulting product optionally converted to its base salt.

The reaction of the compounds of formulas II and III may be carried out in the presence of a condensing agent such as dicyclohexylcarbodiimide or the like, or the starting acid of the formula III may be activated by conversion to a mixed anhydride, symic acid, acid halide, activated ester, or Woodward reagents, Κ, N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline, etc. An overview of the acylation methods is given, for example, in Methoden der Organischen Chemie (Houben-Weyl), Volume XV, Part II, p. 1 and others (197-4). Preferably, the acid chloride of formula III is reacted with a compound of formula II.

The ester derivatives of the above general formula I, i.e. those in which R represents a C 1 -C 4 alkyl group, can be converted to the free acids, i.e. to the hydrogen atom R, in a conventional manner. For example, when R is tert-butyl, the corresponding free acid is obtained by treatment with trifluoroacetic acid and anisole.

The product of formula (I) is preferably isolated and purified by crystallization, for example by converting it to the dicyclohexylammonium salt, which salt is then converted to the free acid again by treatment with an aqueous solution of an acid or acidic agent such as potassium hydrogen sulphate.

The hydrolysis or ammonolysis leading to the compounds of the formula I with a hydrogen atom R @ 4 is carried out in a conventional manner.

Esters of formula (I) in which R is C1 -C4 alkyl may be obtained from the corresponding carboxylic acids, i.e., from the above compounds in which R is hydrogen by conventional esterification procedures, for example esterification with a diazoalkane such as diazomethane 1-alkyl-3-p-tolyttriazene, such as 1-n-butyl-3-p-tolyltriazene, and the like.

The starting proline derivatives of formula (II) can be prepared by various methods. For example, the hydroxy- or mercaptoproline of the general formula (V) may be used

A HN — C — COOH ^H (V) to acylate a nitrogen atom is acylated with an acylating agent such as acetic anhydride, acetyl chloride, propionic anhydride, butyric anhydride, • benzyl chloroformate, etc. By reacting a compound of formula V with a protected nitrogen atom

Or, where hal is a halogen atom, preferably iodine, in the presence of silver oxide, sodium hydroxide, sodium hydroxide, and the like, a R 1 moiety is introduced to form the intermediate of formula (VI)

Alkaline hydrolysis of the intermediate of formula (VI) with a base such as barium hydroxide, sodium hydroxide, potassium hydroxide and the like. first, the corresponding free acid (COOH) is obtained and then mineral hydrolysis. of an acid such as sulfuric acid, a starting material of formula II is obtained.

Another method for preparing the starting proline derivatives of formula (II) consists in reacting an ester, preferably a methyl ester, of a nitrogen-protected tosyloxyproline derivative of formula (VII): chr-N-C-C (() represents an alkyl group and

Ts is as defined below, with the sodium salt of formula VIII

R 1 -X-Na (VIII) to form intermediate IX

chrN — C

XR-COOa-1k

H (IX)

In formula VII, Ts is a residue of the formula and the nitrogen protecting group is either benzyloxycarbonyl, which is preferred, or any other commonly used acyl protecting group. In this reaction, when the tosyloxy group is in the cis configuration, the product containing the XRi moiety is in the trans configuration, and when the tosyloxy group is in the trans configuration, a product containing the XRi moiety is in the cis configuration. The alkyl ester group is then removed from the intermediate of formula (IX) and the hydrobromide of the starting proline derivative of formula (II) is obtained by treatment with hydrogen bromide, which can then be condensed with the acid of formula (III) or preferably with the acid chloride. .

The starting proline derivatives of the formula II in which X is a sulfur atom and the XR 1 moiety is attached at the 3-position of the proline moiety can also be obtained by reacting an ester, preferably tert-butyl ester, of 1,2-dehydroproline of the formula X

(X) with an acylating agent such as benzyl chloroformate, acetyl chloride and the like to form a 4,5-dehydroderivative of formula XI chromium (XI) which is then reacted with mercaptan of formula

R 1 -SH to give the product of formula XII chr-N-1-COOaXk (λ v) wherein the group -S-R 1 is in the trans-configuration. . The nitrogen protecting group and the alkyl group are then removed to give the desired starting material.

The starting proline derivatives of the general formula (II) in which R 1 represents a phenyl group. optionally substituted as described above,. can also be obtained by reacting an N-protected proline benzyl ester of formula V with an appropriate alcohol of formula R1-OH in the presence of triphenylphosphine and diethyl azodicarboxylate, according to the procedure described by Bittner et al. in Chemistry and Industry, p. ). Cleavage of the nitrogen protecting group and the benzyl ester group then provides the starting material of formula II.

For further illustrative information regarding the preparation of the starting materials and intermediates, reference may also be made to the following publications: Ondetti et al., U.S. Pat. Nos. 4,046,889, 4,105,776 and U.S. Pat.

154 935; Neuberger, J. Chem. Soc., 1945, pp. 429-432; Patchett et al., J. Amer Chem. Soc. 79, pp. 185-192 (1957); Baer et al., Can. J. Biochem. and Phys., 37, 583 (1959); Sheehan et al., J. Amer. Chem. Soc. 85, 3863-3865 (1963); Magerlein, J. Med. Chem. 10, pp. 1161-1163 (1967). The procedures described in these publications can be used as general methods for the synthesis and stereoconversion of compounds used in the present invention.

Further experimental details are set forth in the Examples below which describe preferred embodiments and also serve as model procedures for the preparation of other compounds of the invention.

The compounds of the present invention form salts with a wide variety of inorganic or organic bases. The salt-forming ions derived from these bases may be metal ions, for example aluminum, alkali metal, such as sodium or potassium, alkaline earth metal, such as calcium or magnesium, or amine-derived ions, many of which are known for this purpose, for example aralkylamines such as dibenzylamine, N, N-dibenzylethylenediamine, lower alkylamines such as methylamine, tert-butylamine, procaine, lower alkylpiperidines such as N-ethylpiperidine, cycloalkylamines such as cyclohexylamine or dicyclohexylamine, 1-adamantanamine or benzathine. Salts derived from amino acids such as arginine, lysine and the like are also contemplated. Physiologically acceptable salts such as sodium or potassium salts may be used in medicine as described below, and these salts are preferred. These and other salts, which are not necessarily physiologically acceptable, are useful for the isolation and purification of products suitable for the purposes described below, as illustrated in the Examples with dicyclohexylamine and cyclohexylamine. The salts are prepared by reacting the acid compound with a base equivalent to give the desired basic ion, in a salt precipitating medium or in an aqueous medium followed by lyophilization. The free acid product may be obtained from the salt by conventional neutralization, for example with potassium bisulfate, hydrochloric acid and the like.

The compounds of the invention inhibit the conversion of the angiotensin I decapeptide to angiotensin II and are therefore useful in the control or alleviation of hypertension. The compounds of the invention interfere with the renin-angiotensinogen-> angiotensin I-angiontensin II process by inhibiting the enzyme converting angiotensin I to angiontensin II and suppressing or eliminating the formation of the angiotensin II presoric agent. Thus, administration of a hypotensively effective amount of a composition comprising one or more compounds of Formula I or physiologically acceptable salts thereof results in a reduction or amelioration of hypertension in a mammal suffering from the disease.

For lowering blood pressure is appropriate one •

a shock dose, or preferably two to four sub-daily doses, ranging from about 0.1 to 100 mg of active ingredient per kilogram per day, preferably from about 1 to about 50 mg / kg / day, as indicated by model experiments on animals described by SL Engel, TR Schaeffer, Μ. H. Waugh and B. Ruby in Proc. Soc. Exp. Biol. Copper. 143, 483 (1973). The active compounds are preferably administered orally, but can also be administered parenterally, such as subcutaneously, intramuscularly, intravenously or intraperitoneally.

The compounds of the invention may be used to lower blood pressure in the form of compositions such as tablets, capsules or elixirs for oral administration or sterile aqueous solutions or suspensions for parenteral administration. For the preparation of a unit dose, commonly known in pharmaceutical practice, about 10 to 500 milligrams of a compound or mixture of compounds of Formula I, or a physiologically acceptable salt thereof, is combined with a physiologically acceptable diluent, carrier, binder, preservative, stabilizer, flavoring. or another excipient. Said compositions or preparations contain an amount of active ingredient such that, when administered, a suitable dosage will be obtained within the above range.

Illustrative of materials that can be used for the preparation of tablets, capsules and the like include binders such as gum arabic, gum tragacanth, corn starch or gelatin, carriers such as secondary calcium phosphate or microcrystalline cellulose, tablet disintegrating agents such as corn starch, potato starch, alginic acid and the like; glidants such as magnesium stearate; sweeteners such as sucrose, lactose or saccharin; flavorings such as peppermint oil, oil of wintergreen or sour cherry flavor. When the unit dosage form is a capsule, it may contain, in addition to materials of the above type, a liquid carrier such as a fatty oil. Various other materials may be used to coat or otherwise modify the physical properties of the unit dosage forms. For example, tablets may be coated with a sheat, sugar, or both. Syrups or elixirs may contain the active ingredient, sucrose as a sweetening agent, methyl and propylparabens as preservatives, a coloring agent and flavoring agents such as cherry or orange flavor.

Sterile injectable preparations may be prepared according to conventional pharmaceutical practice by dissolving or suspending the active ingredient in a vehicle such as water for injection, in a natural vegetable oil such as sesame oil, cocoa oil, peanut oil, cottonseed oil and the like.

Preferred embodiments of the method of the invention are illustrated by the following examples. These examples also serve as exemplary examples for the preparation of other compounds which can be prepared by substituting appropriately substituted analogs for the reagents in the examples.

Example 1

- (3-Acylthio-1-oxopropyl) -trans-4-methoxy-L-proline

a) N-acetyl-trans-4-hydroxy-L-proline

To a suspension of 26.2 g (0.2 mol) of trans-4-hydroxy-L-probnu in 400 ml of acetic acid was added 26 ml of acetic anhydride with stirring. After stirring at room temperature for 2 hours, the solid material gradually dissolved. Evaporate the solvent to a 2 L flask and evaporate the solvent on a rotary evaporator at a bath temperature of 45 ° C. The syrupy residue weighing 57.5 g is diluted with 100 ml of ether to give a crystalline solid. The material thus obtained, weighing 35.7 g, is sprayed and suspended in 100 ml of ether, cooled and filtered to give 33.8 g (98%) of N-acetyl-trans-4. m.p. 128-131 [deg.] C. After recrystallization of 0.5 g of this product from 5 ml of acetonitrile, 0.45 g of a colorless solid is obtained, m.p. _d 25 ~ -92 ° (c = 1% in ethanol) nolu).

b) N-Acetyl-trans-4-methoxy-L-proline methyl ester

A mixture of 30.0 g (0.17 mol) of N-acetyl-trans-4-hydroxy-L-proline and 130 g of silver oxide is sprayed in a mortar and the resulting homogeneous mixture is added to a 1 liter flask containing 300 ml of acetone. To the suspension. 130 ml of methyl iodide are added in portions while stirring, the temperature below 40 ° C being determined by cooling in the water bath. After stirring for 7 hours, the mixture was allowed to stand overnight, the solid material was filtered off, washed thoroughly with acetone, and the filtrate was concentrated on a rotary evaporator. The syrup residue, 38.3 g, was redissolved in 350 ml of acetone and treated again with 130 g of silver oxide and 130 ml of methyl iodide to give 41 g of residue. The latter residue distilled to give 32.2 g of distillate boiling at 130-140 ° C / Pa. After trituration in 30 ml of cyclohexane and cooling, 31.4 g of an almost colorless solid N-acetyl-trans-4-methoxy-L-proline methyl ester of melting point 71-75 ° C are obtained, which recrystallized from 31 ml of ethyl acetate. 76 g (66%) of a colorless solid, m.p. 76 DEG-77 DEG C. and optical rotation [.alpha.] D @ ²⁵ = -83 DEG (c = 1% in ethanol).

c) trans -4-methoxy-L-proline

To a solution of 27.0 g · [0.085 mol] of barium hydroxide octahydrate in 525 ml of water (ca. 3.3 N) is added with stirring 11.0 g (0.05 mol) of N-methyl-trans-4-methoxy-L- proline. The resulting solution was stirred at 18-20 ° C for 3 hours, then cooled and dilute sulfuric acid (8.8 g of concentrated sulfuric acid in 20 mL of water) was added. The acid suspension was allowed to stand overnight, then filtered through a pad of diatomaceous earth. The resulting milky-cloudy filtrate is concentrated on a rotary evaporator at 50 ° C using a high-efficiency vacuum pump. 121 g of a milk residue are obtained, to which dilute sulfuric acid (19.0 g of concentrated sulfuric acid in 75 ml of water) is added, and the resulting mixture is stirred at reflux for 3 hours. After cooling to 30 ° C, 48 g of barium hydroxide octahydrate are added in portions and then the pH is adjusted to 6.0-4.0 with dilute sulfuric acid. The mixture was allowed to stand overnight, then filtered through a pad of diatomaceous earth and the milky cloudy filtrate was concentrated as above. 50 g of a colorless dry residue are obtained which is triturated with 200 ml of hot chloroform. The mixture was filtered through a pad of diatomaceous earth to remove barium sulfate and the slightly cloudy filtrate was concentrated on a rotary evaporator. The gelatinous residue, 17.7 g, was suspended in 100 ml of ether and filtered to give 7.5 g (94%) of an almost colorless solid melting at 185-190 ° C with decomposition. This material was suspended in warm acetonitrile (30 ml), cooled and filtered. 4.0 g (50%) of a colorless solid trans-4-methoxy L-proline melting under decomposition at 209 DEG -211 DEG C. with optical rotation [ _{.alpha.] D} @ 25 = -75 DEG (c = 1% in ethanol) are obtained. .

d) 1- (3-acetylthio-1-oxopropyl) -trans-4-methoxy-L-rolin

To a solution of 3.5 g (0.024 mol) of trans-4-methoxy-L-proline in 50 ml of water was added 3 g of sodium carbonate while stirring and cooling to 5 ^° C. A solution of 4.0 g (0.024 mole of 3-acetylthiopropionic chloride in 5 ml of ether) was then added over 10 minutes, while 3 g of sodium carbonate was added during the addition to maintain the pH at about 8.0. After stirring for an additional hour under ice-cooling, 25 ml of water were added, followed by a solution of 5 ml of concentrated hydrochloric acid in 25 ml of water (carbon dioxide evolution), and the resulting strongly acidic solution was saturated with sodium chloride and extracted four times. The organic phases were combined, dried (MgSO4), filtered and the solvent was evaporated to give 6.0 g (90%) of a colorless syrup-like 1- (3-acetylthio-1-oxo-propyl) triazole. - _m ei ^ of ^ o ^ X ^^ - L-proline. · the acid is dissolved in 25 ml ethyl acetate and treated with 4.7 g dicyclohexyl

2.2 B11 8

12 amine. The mixture becomes a solution which solidifies rapidly. Add another 15 ml. ethyl acetate, digested with heating on a steam bath, cooled and filtered. 8.7 g are obtained. 170 DEG-172 DEG C., which, after crystallization from 00 ml of acetonitrile, gives 8.3 g (75 DEG C.) of a colorless solid, m.p. 171 DEG-173 DEG C. and an optical rotation of [.alpha.] D @ ²⁵ = - ⁰ ^ -35 (c = 1% V: ethanol).

Dicyclohexylaraonium salt is converted to 1- (Z-асеЬуИЬю-Ьох.оргору!) .- trans-4-ethoxy-L-proline so that. with 8.0 g of the salt is suspended in 60 ml of ethyl acetate; the suspension is cooled in ice and 60 ml of a 0% hydrogen sulphate solution are added in portions. potassium ,. The clear layers were separated and the aqueous phase was separated. extracted twice with 60 ml of ethyl acetate. The phases are combined, dried over magnesium sulphate and, after filtration, the solvent is evaporated. 4.6 g (80%) of a colorless syrup product are obtained.

Example 2

1- (3-mercapto-1-oxopropyl) -trans-4-methoxy-L-proline

To the 4.6 g (0.017 mol) of 1- (3-acetylthio-1-oxopropyl) -trans-4-methoxy-L-proline obtained in Example 1 was added a cold solution of 9 ml of concentrated ammonia in 22 ml of water. The base dissolved in about 30 minutes and the resulting solution was allowed to stand at room temperature for 2 hours under argon. The reaction solution was cooled, extracted. twice with 25 ml of ethyl acetate, ethyl ^e fathers extracts were discarded znovu.převrství solution and 25 ml of ethyl acetate, acidified to 17th mL of water and hydrochloric acid (1: 1). The mixture is shaken, the layers are separated and the aqueous phase is extracted three times with 25 ml of ethyl acetate. The organic phases are combined; After evaporation of the solvent on a rotary evaporator, 2.3 g (59%) of a colorless solid are obtained; syrup-1- (3-mercapto-1-oxopropyl jrans- J 1 = methoxy-L-proline optical. rotation [ «jo ^05.02. = -60 ° (с = 1% in ethanol) and Rf = 0. 49 (silica gel, methanol, nitroproside reagent detection).

Analysis for:

CaHisNOdS. 1/4 H2O:

calculated:

C: 45.46%, H: 6.57%, N: 5.87%,

W: 13.48%;

found:

C: 45.42%, H: 6.78%, N: 5.96%,

S: 13.27 O / o.

An additional 1.1 g of product (total yield 3.4 g, i.e. 87%) is obtained by saturating the aqueous phase with sodium chloride and extracting twice with 25 ml of ethyl acetate.

'The sodium salt is prepared by treating the syrupy material with a sodium bicarbonate solution and lyophilizing the mixture.

Example 3 trans-1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -3-methoxy-L-proline

A solution of 4.3 g (0.029 mole; trans-4-methoxy-L-proline in 50 ml of water) is cooled to 5 ° C with stirring and 3.0 g of sodium carbonate are added thereto. 5.2 g (0.029 mol) D -3- (acetylthio) -2-methylpropionyl chloride in 5 ml of ether was added while maintaining the pH at 8.0 by periodic addition of 3 g of sodium carbonate. After stirring for 5 hours under cooling, 25 ml of water were not added first and then a solution of 6 ml of concentrated hydrochloric acid in 25 ml of water (evolution of carbon dioxide) was added. The solution was extracted four times with 50 ml ethyl acetate, the organic phases were combined, dried over magnesium sulphate and after filtration the solvent was evaporated. Yield: 6.1 g (73%). 3- (acetylthio) -2-methyl-1-oxo-propyl] -4-methoxy-L-proline in the form of a pale yellow syrup residue which was dissolved in 50 ml of ethyl acetate. To the solution was added a solution of 4.0 g of dicyclohexylamine in 20 ml of ethyl acetate. After cooling overnight, the almost colorless solid material was filtered off and dried. 6.7 g of product are obtained, m.p. 175 to 177 ^Q C and optical rotation [Ь ²⁵ = s =. —55 ° (с - 1% in ethanol). After crystallization from 60 ml of acetonitrile, 5.6 g of an almost colorless solid dicyclohexylammonium salt (41%) having a melting point of 179 DEG-181 DEG C. and an optical rotation of [.alpha.] D @ 20 were obtained. ⁵ - 62 ^° (с = 1% in ethanol).

The dicyclohexylammonium salt is converted to the free acid by suspending 5.5 g of the salt in 50 ml of ethyl acetate, cooling the suspension in ice and adding 50 ml of 10% potassium hydrogen sulphate solution. The layers were separated and the aqueous layer was extracted twice with 50 mL of ethyl acetate. The organic phases are combined, dried over magnesium sulphate. The mixture was filtered and the solvent was evaporated to give 3.4 g (41 percent) of an almost colorless syrupy trans-1- [3- (3-c (acetylthio) -4-methyl-1-oxo-propylene)]. 1,4-Methoxy-h-proline.

EXAMPLE 4 Trans-4-Methoxy-1 (PT3-percapto-2-methyl-1-oxopropyl) -L-proline

To 3.4 g of trans-1- [D-3- (acetylthio) -2-methyl-1-oxopropylindan-3-methoxy-piperidine, a cold solution of 8 ml of concentrated ammonia in 20 ml of water was added. The base dissolved in about 10 minutes, the resulting solution was dissolved. The mixture was allowed to stand at room temperature for 2 hours, then cooled, extracted twice with 20 ml of ethyl acetate, overlaid with 20 ml of ethyl acetate and acidified with 15 ml of a 1: 1 mixture of water and hydrochloric acid. The resulting mixture was saturated with sodium chloride, the layers were separated, and the aqueous phase was extracted three times with 20 mL of ethyl acetate. The organic phases were combined, dried over magnesium sulphate and after filtration the solvent was evaporated. 2.9 g (100%) of an almost colorless trans-4-methoxy-1- [D-3-mercapto-2-methyl-1-oxopropyl] -L-proline are obtained with an optical rotation [α] = ²⁵ = -80 ° (c = 1% in ethanol) and R f = 0.53 (methanol, silica gel, nitroprusside reagent detection).

Analysis for:

C10H17NO4S. 1/4 HžO:

calculated:

C: 47.69%, H: 6.83%, N: 5.56%,

S: 12.73%;

found:

0: 47.90 0/0, H: 6.84%, N: 5.85%,

S: 12.76%.

Example 5 trans-1- [D-3- (acetylthm) -2-methyl-Toxopropyl] -4-ethoxy-L-proline

Using the procedure described in Example 3, substituting trans-4-methoxy-L-proline with an equivalent amount of trans 4-ethoxy-L-proline [J. Copper. Chem., 10, 1161 (1967)] yields trans-1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -4-ethoxy-L-proline. The product is purified by conversion to the dicyclohexylammonium salt, m.p. crystallization from isopropanol at 170-172 ° C, optical rotation [ «] d ² 5 = -64 ° (c = 1% in ethanol).

7.75 g of this salt was converted to the free acid by treatment with potassium bisulfate solution using the procedure described in Example 4. 4.85 g of an almost colorless syrup-like trans-1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -4-ethoxy-L-proline are obtained.

Example 6 trans-4-ethoxy-1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-proline

To 4.85 g of the product obtained in Example 5 was added a cold solution of 9 ml of concentrated ammonia in 22 ml of water under argon. Analogously treating the mixture as in Example 4, 4.2 g (100 percent) of an almost colorless syrup-like trans-4-ethoxy-1- (D-3-carcapto-2-methyl-1-oxopropyl) -L-proline are obtained with an optical rotation [α] ²⁵ = -80 ° (c = 1% in ethanol) and Rf equals 0.64 (methanol, silica gel, nitroprusside reagent detection).

Analysis for:

C11H19NO4S:

calculated:

C: 50.55 0/0, H: 7.33%, N: 5.36%,

S: 12.27 ° / o;

found:

C: 50.34%, H: 7.34%, N: 5.39%,

S: 12.11%.

Example 7 cis-1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -4-methoxy-L-proline a] N-benzyloxycarbonyl-cis-4-hydroxy-Lproline g (0.038 mol) N The benzyloxycarbonyl-4-keto-L-proline is dissolved in 300 ml of methanol and reduced according to the procedure described in J. Am. Chem. Soc., 79, 189 (1957) using 5.8 g (0.15 mol) of sodium borohydride in methanol. 20 ml of water were obtained, 8.7 g of a foamy product were dissolved in 30 ml of ethanol, 3.5 g of cyclohexylamine in a small amount of ethanol were added thereto, and the resulting solution was diluted with ether to a volume of 500 ml. Crystallized cyclohexylammonium salt precipitated rapidly with a glass rod, yielding 10.8 g, m.p. 163 DEG-165 DEG C. The cyclohexylammonium salt was treated with 30 ml of 2 N hydrochloric acid and extracted four times with 50 ml of ethyl acetate each time. 8 g of N-benzyloxycarbonyl-cis-4-hydroxy-L-proline as a glassy material.

b] N-Benzyloxycarbonyl-cis-4-methoxy-L-proline methyl ester

In an analogous manner to that. in Example 1 (b), 13.9 g (0.052 mol) of N-benzyloxycarbonyl-cis-4-hydroxy-L-profin were treated twice with 40 g of silver oxide and 40 ml of methyl iodide, first in 100 ml of acetone; then in 120 ml of acetone

17.5 g (100%) of N-benzyloxycarbonyl-cis-4-methoxy-L-proline methyl ester as a yellow oil.

c] N-benzyloxycarbonyl-cis-4-methoxy-L-proline

17.5 g (ca. 0.052 mol) of N-benzyloxycarbonyl-cis-4-methoxy-L-proline methyl ester are dissolved in 135 ml of methanol, 32 ml [0.064 mol] are added thereto at a temperature of from -1 to 4 ° C. The mixture was allowed to stand for 1 hour at 0 ° C and then overnight at room temperature. After evaporating about half of the solvent on a rotary evaporator, the resulting solution was diluted with 300 mL of water, washed with ether (the washings were discarded), acidified with 12.5 mL of water / hydrochloric acid (1: 1) to pH 2 while cooling, and extracted. ethyl acetate (4 x 150 ml). The extracts were combined, dried (MgSO4), filtered and the solvent was evaporated. 15 g of an orange-yellow syrup are obtained, which is dissolved in 60 ml of ethanol. 6 g of cyclohexylamine in 10 ml of ethanol are added to the solution and the mixture is diluted with ether to a volume of 900 ml. After inoculation and scratching the walls of the container with a glass rod, the crystals of N-benzyloxycarbonyl-cis-4-methoxy-L-proline are cyclo-cyclohexylammonium salt. After cooling overnight, 10.2 g of the product are obtained. 148 DEG-150 DEG C. (melting at 144 DEG C.) and optical rotation [.alpha.] D @ ²⁶ = -35 DEG (c = 1% in ethanol) which, after recrystallization from 40 ml. m.p. 15.0-152 degrees. Celsius (melts at 145 ° C) and _; Optical rotation [α] D ⁶² - 34 ° (c - 1% in ethanol).

Treatment of the cyclohexylammonium salt with hydrochloric acid afforded 6.9 g. (48 percent) of N-benzyloxycarbonyl-cis-4-m ethoxy-L-proline as a pale yellow viscous syrup with an optical rotation [ «Id ²⁶ = -32 DEG (с = 1% in ethanol).

d) cis-4-methoxy-L-proline

A mixture of 6.8 g of N-benzyloxycarbonyl-cis-4-methoxy-L-proline, 210 ml of a mixture of methanol and water (2: 1) and 2.3 g of 5-palladium on carbon was hydrogenated in a hydrogenation apparatus for 4 hours. hydrogen pressure 0.3. MPa. The resulting mixture was filtered to remove the catalyst and the filtrate was evaporated. 3.15 g of an off-white solid melting at 218-220 ° C with decomposition. After crystallization of a sample of the product from a methanol mixture, a colorless cis-4-methoxy-L-proline melting under decomposition at 224 to 226 ° C is obtained with an optical rotation of [α] ²⁵ = -42 ° (c = 1% in methanol).

Analysis for:

CeHnNOó:

calculated:

C: 49.64%, H: 7.64%, N: 9.65%;

ΓΊ Q 1 Л7 βΤΊ ΓΥ ·

C: 49.63%, H: 7.71%, N: 9.54%.

e) cis-1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -4-methoxy-L-proline

The procedure described in Example 3 was 3 g (0.021 mol). cis-4-methoxy-1-proline and 4.2 g (0.023 mol) of D-3-acetylthio-2-methylpropionyl chloride in 5 ml of ether, reacted in 60 ml of water, in the presence of sodium bicarbonate, K, adjusting the pH initially about 8.5 ml and about 20 ml (25% v / v) of sodium carbonate are required to maintain the pH value during the acylation of 7.5 to 8.4. The resulting crude viscous product (6.4 g) is dissolved in 3.9 g of dicyclolyloxylamine in 20 ml of ethyl acetate are added to 50 ml of ethyl acetate and to the solution. The product which crystallizes from the solution is filtered off and dried, yielding 6.6 g _; dicyclineexylampni; salts having a melting point of 172 and? 174 DEG C. (at 170 DEG C.). λ optical rotation, [α] ¹² D = - 60 ° (с = 1% in ethanol); 6.5 g of this material, after recrystallization from 35 ml of acetonitrile, gave 6 g of a colorless solid dicyclohexylammonium salt, m.p. 173-175 ° C. (rotates at 170 degrees Celsius) with an optical rotation of [ _.alpha. ] _D @ ²³ = -60 DEG (c = 1% in ethanol).

Analysis for:

C12H19NO0S. C12H23N;

calculated:

C: 61.24%, H: 9.00%, N: 5.95%,

S: 6.81%;

found:

C: 61.16%, H: 8.81%, N: 5.95%,

S: 6.67%.

Using the procedure described in Example 3, the dicyclohexylammonium salt is converted to the free acid by suspending 5.9 g of the salt in 60 ml of ethyl acetate, cooling the suspension in ice and adding 60 ml of a 10% hydrogen solution. potassium sulfate. The layers were separated and the extracted phase was extracted four times with 50 ml of ethyl acetate each time. The organic phases are combined, dried with magnesium sulphate and, after filtration, the solvent is evaporated. 3.5 g (60%) of colorless cis-1- [D-3 (acetylthio) -2-methyl-1-oxopropyl] -4-methoxy-t-proline are obtained, melting after trituration with ether at 90 DEG-90 DEG. 92 ° C. optical rotation [ajo ²⁶ = -139 DEG (c = 1% in ethanol) and R _f = 0.63 (methanol, silica gel).

Analysis for:

C12H19NO5S;

calculated:

C, 49.81%, H1 6.62%, N: 4.84%;

found:

C: 49.85%, H: 6.66%, N: 4.97%.

Example 8 cis-4-methoxy-1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-proline

As described in Example 4, 2.9 g (0.01 mol) of cis-1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -4-methoxy-L-proline are hydrolyzed in 15 ml. water containing 6.5 ml of concentrated ammonia. 2.3 g (93 percent) of an extremely viscous cis-4-methoxy-1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-proline are obtained, which on standing is converted to a waxy mass. The product has an optical rotation of [α] D ²⁶ = -88 ° (c = 1% in ethanol).

Example 8a

Cis-4-methoxy-1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-proline 1-adamantanammonium salt

To a solution of 0.55 g (0.0022 mol) of cis-4-methoxy-1- (D-3-mercapto-2-methyl-1-oxopropylpropyl) -L-proline in 15 ml of ethyl acetate was added a warm solution under argon. 0.34 g (0.0022 mol) of 1-adamantanamine in 10 ml of ethyl acetate precipitates the salt. After cooling for 3 hours, the colorless solid product was filtered off under argon (the material stubbornly retains the solvent), washed with a small amount of cold ethyl acetate, and dried in vacuo for 20 hours. 0.7 g (79%) of cis-4-methoxy-1- (D-3-methyl-cap-2-yl) -ethyl-1-propyl) -L-proline 1-adamantanammonium salt, m.p. 215 up to 217 degrees Celsius (sintered at 210 ° C, decomposes at 220 ° C) with an optical rotation of [α] _D ² = -60 ° (c = 1% in methanol).

Example 9 cis-4- (4-fluorophenoxy) -1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-proline

a) C ^'s-4- (4-fluorophenoxy-L-proline

To a solution of 8.4 g (0.024 mol) of N-benzyloxycarbonyl-trans-4-hydroxy-L-proline benzyl ester [see Baer et al. Can. J. Biochem. and Phys, 37, 583 (19519)], 4.0 g (0.036 mol) of 4-fluorophenol and 9.27 g (0.036 mol) of triphenylphosphine in 75 ml of dry trtrahydrecurane are added dropwise over 1 hour to 6.2 g (0.036 mol) mol) of dirthylazodicarboxylate in 25 ml of tetrahydrofuran. The reaction mixture was stirred at room temperature overnight, then evaporated to dryness and ether (100 ml) added. The precipitated triphenylphosphine and diethyl azodicarboxylate are filtered off and chromatographed on a silica gel column to give 8.1 g of a mixture containing about 70% of N-benzyloxycarbonyl-cis-4- (4-fluorophenoxy) -L-proline benzyl ester.

A solution of 7.5 g of the above benzyl ester mixture is hydrogenated at room temperature under 100 psi in the presence of 0.8 g of 10% palladium on carbon catalyst.

A white precipitate forms during the reaction. After the hydrogen consumption has subsided, the mixture is filtered and the filter cake is digested three times with 125 ml of hot methanol each time. Evaporation OF AN · methanol solution to dryness affording 3.2 ^GC: S-4-r4-flucгfrncxy) -L-pгclinu mp 235-236 ° C.

Analysis for:

C11H12FNO3. 1/3 H2O:

calculated:

C: 57.14%, H: 5.48%, N: 6.06%,

F 8.22%, found:

C: 56.94%, H: 5.19%, N: 5.94%,

F: 7.97%.

b] 1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -cis-4- (4-fluorophenoxy) -L-prc-m

To a suspension of 2.25 g (0.01 mol) of cis-4- (4-fluorfrnoxy) ^{-L-PI-morpholine} in 125 ml dry pyridine was added at room temperature 1.0 g (0.01 mol) and 2 trirthylaminu G (0.011 mol) of D-3- (acetylthio) -2-methylpropyl chloride. The reaction mixture was stirred at room temperature overnight, then evaporated to dryness, the residue was taken up in water, the solution was layered with ether and acidified with 10% hydrochloric acid. The aqueous layer was extracted again with ether, the ether layers were combined, washed with water and dried over sodium sulfate and evaporated to dryness. 3.9 g of residue are obtained, which is chromatographed on 250 ml of silica gel with ether as the eluent to give the fraction containing the desired product. The column was washed with methanol and the methanolic eluate was rechromatographed on a short silica gel column to give additional product. This procedure is repeated once more. A total of 1.2 g of No ^: 1- [D-3-

- (acetylthio) -2-methyl-1-oxopropyl] -cis-4-

- (4-fluoro-phenoxy) -L-proline.

c) cis-4- (4-fluoro-phenoxy) -1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-proline

1.2 g of - [[D-3- (acetylthiol-2-methyl-11-oxo-propyl) (4-fluorophenyl) -L-proline] are dissolved in 25 ml of methanol and the solution is treated with argon for 40 minutes under argon. 5 ml of concentrated ammonia solution, the volatiles were evaporated, the residue was overlaid with ethyl acetate and the aqueous layer was acidified with 10% hydrochloric acid, the layers were separated and the acidic layer was washed with ethyl acetate. Evaporation of the solvent gave 1.1 g of a solid foam-like residue containing cis-4- (4-: fluorophenoxy) -1- (D-3-mercapto-2-methyl-1-methoxypropyl) - L-proline.

Analysis for:

C15H18FNO4S. 1/3 H2O:

calculated:

C: 54.05%, H: 5.70%, N: 4.20%,

F: 5.70%, S: 9.60%, found:

G: 54.04%, H: 5.71%, N: 4.05%,

F: 5.40%, S: 9.61%.

TLC: _Rf = 0.30 (detection by UV light, SH reagent (yellow spot) and vanillin (yellow spot)); [ _.alpha. ] _D @ ²⁵ = -80 DEG (c = 1% in chloroform).

Example 10

1- (D-3-mercapto-2-methyl-1-oxopropyl) -cis-4-phenylthio-L-proline

(a) N-Benzyloxycarbonyl-cis-4-phenylthio-L-proline methyl ester

0.85 g (0.037 mol) of sodium metal is dissolved in 40 ml of absolute ethanol, and 3.7 ml (0.036 mol) of thiophenol are added to the solution with stirring, followed by 7.5 g (0.017 mol) of N-benzyloxycarbonyl-trans-methyl ester. -4-tosyloxy-L-proline [see J. Am. Chem. Soc., 79, 191 (1957)]. The latter gradually goes into solution, but soon thereafter a solid product begins to precipitate. After stirring for four hours and then standing overnight at room temperature, most of the ethanol was rotovapped and the predominantly solid was stirred with 120 ml of dichloromethane and 60 ml of water. The layers were separated (a small amount of methanol was added to break the emulsion) and the aqueous phase was extracted twice with 60 ml of dichloromethane each time. The combined organic phases were washed with 100 ml of saturated sodium chloride solution, dried over magnesium sulphate and the solvent was evaporated. 6.5 g (100%) of N-benzyloxycarbonyl-cis-4-phenylthio-L-proline methyl ester are obtained in the form of a yellow viscous oil.

b) N-benzyloxycarbonyl-cis-4-phenylthio-L-proline

6.5 g (0.017 mol) of the methyl ester prepared in a) are dissolved in 55 ml of methanol, 13 ml (0.026 mol) of 2 N sodium hydroxide are gradually added thereto at a temperature of from -1 to 4 ° C, the mixture is stirred for 1 hour. The mixture was stirred at 0 ° C and then allowed to stand at room temperature for about 16 hours. After evaporating about half of the solvent on a rotary evaporator, the cooled solution was diluted with 100 ml of water, washed with 60 ml of ether (the wash liquid was discarded), overlaid with 70 ml of ethyl acetate and acidified with 4.8 ml of a mixture of hydrochloric acid and water. 1: 1 ratio. After phase separation, the aqueous layer is extracted three more times with 40 ml of additional ethyl acetate, the combined organic layers are dried over magnesium sulphate and evaporated. 5.9 g of a yellowish viscous oil are obtained, which is dissolved in 30 ml of ethanol, 1.9 g of cyclohexylamine in 3 ml of ethanol are added and the mixture is diluted with ether to a volume of 330 ml. After inoculation, crystalline cyclohexylammonium salt precipitates, melting at 148-151 ° C (sintered at 135 ° C) and weighing 5.3 g after cooling for about 16 hours. This material is combined with 1.5 g of the identical product from the previous experiment, the mixture is stirred with 200 ml of boiling acetonitrile and cooled. 6.3 g of a colorless cyclohexylammonium salt of melting point 152 DEG-155 DEG C. (sintered at 137 DEG C.) and optical rotation [.alpha.] D @ ²⁶ = -24 DEG (c = 1% in ethanol) are obtained.

The cyclohexylammonium salt was suspended in 25 ml of ethyl acetate and 25 ml of 1 N hydrochloric acid was added to the suspension with stirring. Once two clear layers were formed, they were separated and the aqueous phase was extracted three more times with 25 ml of ethyl acetate each time. The combined organic layers were dried over magnesium sulfate and the solvent was evaporated. 5.0 g (65%) of N-benzylcarbonyl-cis-4-phenylthio-L-proline are obtained in the form of an almost colorless, very viscous syrup.

cis-4-phenylthio-L-proline hydrobromide

To 4.9 g (0.014 mol) of N-benzyloxycarbonyl-cis-4-phenylthio-L-proline is added 25 ml of 30-32% hydrogen bromide in acetic acid, the reaction vessel is sealed and the mixture is stirred with a magnetic stirrer. After 1 hour, the orange-yellow solution was diluted with ether to a volume of 250 ml, precipitating the product as a heavy oil which crystallized gradually after seeding, trituration and cooling. After stirring for 1 hour under ice-cooling, the material was filtered off under nitrogen, washed with ether, suspended in fresh ether, cooled for about 16 hours and then filtered again. This gave 3.2 g (77 percent) of a colorless solid cis-4-phenylthio-L-proline hydrobromide with a melting point of 106-109 ° C (sintered at 99 ° C) with an optical rotation of [α] D ²⁶ -3 ° C = 1% in methanol).

d) 1-) D-3- (acetylthio) -2-methyl-1-oxopropyl] -cis-4-phenylthio-L-proline

In an analogous manner to Example 1 (d), by reaction of 3.0 g (0.0094 mol) of cis-4-phenythio-L-prolinhydrohromide and 2.0 g (0.011 mol) of DS-acetylthio-4-methylpropiononyl chloride in 25 ml of water (using about 15 ml of a 20% sodium carbonate solution to maintain a pH of 8.0 to 8.4) gives 3.8 g of a light yellow viscous oil. The dicyclohexylammonium salt of this product (prepared in 30 ml of ethyl acetate using 1.8 g of di-cyclohexylamine), isolated in two portions, is 2.9 g and melts at 184-188 degrees Celsius (sintered at 180 ° C). After trituration with 15 ml of acetonitrile, 2.4 g of a colorless solid dicyclohexylammonium salt of melting point 184 DEG-186 DEG C. (sintered at 180 DEG C.) with an optical rotation of [.alpha.] D @ 26 = -75 DEG ( _c = 1 DEG) are obtained. ethanol).

By analogy to the example, reaction of this dicyclohexylammonium salt with 30 ml of 10% potassium bisulfate solution and extraction with ethyl acetate yielded 2.0 g (59%) of glassy 1- [D-3- (acetylthio) -2-methyl-4-oxopropyl] 1-cis-4-phenylthio-L-proline.

e) 1- (D-S-mercapto-4-methyl-1-oxopropyl) -cis-4-phenylthio-L-proline

In an analogous manner to the example, by reacting 2.0 g (0.0042 mol) of 1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -cis-4-phenylthio-L-proline with 3 0.5 ml of concentrated ammonia in 8.5 ml of water (solid ammonium salt of the product precipitated from the reaction mixture) gave 1.35 g (100%) of a viscous syrupy 1- (D-.alpha.) .Alpha. [ _.alpha. ] _D @ 20 = 10 DEG -124 DEG-cis-4-phenylthio-L-proline with an optical rotation of [ _.alpha. ] _D @ 26 = -43 DEG (c = 1% in ethanol).

Example 11 trans-1- (3-mercapto-1-oxopropyl) -3-methylthio-D, L-proline

a) 1,2-dehydroproline tert-butyl ester

To a solution of proline tert-butyl ester (34.2 g, 0.20 mol) in ether (600 ml) was added dropwise with stirring at -5 to 0 ° C over 10 minutes, 21.7 g (23.9 ml, 0.20 mol). ) of freshly prepared tert-butyl hypochlorite [see Org. Syn., Coll. Vol. V, 184 (1973)]. The temperature is maintained at -5 to 0 ° C during the addition. After the addition was complete, the solution was stirred at the above temperature for an additional 5 minutes.

A solution of 7.8 g (0.20 mol) of potassium in freshly distilled tert-butanol dried over calcium hydride is then added rapidly (about 3-5 minutes) to the vigorously stirred solution. After the addition was complete, the temperature of the reaction mixture was about 18 ° C. The reaction flask was removed from the cooling bath and stirred for 30 minutes. The reaction mixture was filtered through diatomaceous earth and the filtrate was concentrated in vacuo. The residue was taken up in ether and the solution was washed several times with water. The ether solution is dried and concentrated in vacuo to a yellow liquid residue of 31.6 g. After addition of a trace amount of hydroquinone, the crude product is distilled to give 22.4 g (66%) of proline tert-butyl ester at boiling point 60. to 62 ° C 13 Pa.

b) 1-Benzyloxycarbonyl-4,5-dihydro-1H-pyrrole-4-carboxylic acid tert-butyl ester

A solution of 1,2-yehoproproline tert-butyl ester (16.9 g, 0.1 mol) in dichloromethane (70 ml) was cooled to -10 ° C under argon and a 14.2 ml (0.1 ml) solution was added dropwise over 30 minutes. mol) of freshly distilled benzyl chloroformate (bp 62-64 ° C / 53 · Pa) in 70 ml of dichloromethane. After stirring for a further 30 minutes, a solution of 15.22 g (0.1 mol) of 1,5-diazabicyclo [5.4.0] undec-5-ene in ml of dichloromethane was added over 20 minutes. The cooling bath was removed, the mixture was stirred at room temperature for 1 hour, washed twice with cold dilute hydrochloric acid and once with saturated sodium carbonate solution, and the resulting solution was evaporated in vacuo to give 18.2 g (60%) of tert-butyl ester 1. benzyloxycarbonyl-4,5-iro-1H-pyrrole-2-carboxylic acid as a light yellow oil.

c) trans-1-benzyloxycarbonyl-3-methylthio-D, L-proline tert-butyl ester

To a solution of 18.2 g (0.06 mol) of tert-butyl 1-benzyloxycarbonyl-4,5-dihydro-1H-pyrrole-2-carboxylic acid tert-butyl ester in 180 ml of dry methanol is added 3.24 g (0.06 mol) of sodium methoxide The mixture was cooled in ice and methanthiol gas was slowly added over 30 minutes. The resulting mixture was stirred overnight at room temperature under argon and diluted aqueous acetic acid was added until a slightly acidic reaction. After one hour of argon flow, the solution was evaporated in vacuo to near dryness, ethyl acetate was added to the residue, the resulting solution was washed twice with saturated sodium carbonate solution, dried and the solvent was evaporated under vacuum. 17 g of a yellow oil are obtained which is chromatographed on 300 g of silica gel with petroleum ether / ether (4: 1) to give 11.1 g of trans-1-benzyloxycarbonyl-3-methylthio-D, L-proline as a colorless oil.

d) trans-3-methylthio-D, L-proline

To 8.4 g (0.024 mol) of trans-1-benzyloxycarbonyl-3-methylthio-D, L-proline was added 45 ml of 4 N hydrobromic acid in acetic acid. After stirring at room temperature for 1 hour, the resulting solution was evaporated in vacuo and the residue was washed twice with ether after addition of a small amount of water. The aqueous solution is applied to a column of 300 ml of ion exchanger and the column is washed with water until the eluate no longer reacts strongly acidic. The product was then washed with aqueous pyridine acetate buffer pH 6.5. The ninhydrin-positive fractions were combined and lyophilized to give 3.4 g (88%) of the material as a white fluff. A small sample of this material was crystallized from methanol to give trans-3-methylthic-D, L proline melting with decomposition at 196-200 ° C (sintering at 192 ° C).

Analysis for:

CeHnOzNS:

calculated:

C: 44.70%, H: 6.88%, N: 8.69%,

S: 19.89%;

found:

C: 44.53%, H: 7.10%, N: 8.61%, S: 19.95%.

e] trans-1- [3- (acetylthio) -1-oxopropyl] -3-methylthio-D, L-proline

3.05 g (0.019 mol) of trans-3-methylthio-D, L-proline are dissolved in 19 ml of 1 N sodium carbonate solution and the solution is diluted to 10 ml with water. The solution was cooled in ice and a solution of 3-acetylthiopropionyl chloride in 20 mL of ether was added with rapid stirring while maintaining the pH at 8 by addition of 1 N sodium carbonate. After 30 minutes the pH was no longer changed and the reaction mixture was added. ml of sodium carbonate solution. The layers were separated, the aqueous layer was washed once more with ether, then acidified with 10% potassium hydrogen sulfate solution, and the product was extracted with ethyl acetate. The extract was dried and evaporated in vacuo. 5.2 g of oily material are obtained which, after chromatography on 150 g of silica gel with ethyl acetate as eluent, yields 3.85 g of still somewhat impure trans-1- [3- (acetylthio) -1-oxopropyl] -3-methylthio- D, L-proJinu.

A small sample of the product was dissolved in ether and converted to the dicyclohexylammonium salt, which was recrystallized from ethyl acetate. It is obtained. trans-1- [3- (acetylthio) -1-oxopropyl] -3-methylthio-D, L-proline dicyclohexylammonium salt, melting at 153-175 ° C.

Analysis for:

C11H17O1NS. (CeHn) 2NH:

calculated:

C: 58.44%, N: 8.53%, N: 5.83%,

S: 13.57%;

found:

C: 58.77%, H: 8.57%, N: 5.68%, S: 13.74%.

f) trans-1- (3-mercapto-1-oxopropyl) -3-methylthio-D, L-proline

2.05 g (0.007 mol) of trans-1- [3- (acetylthio) -1-oxopropyl] -3-methylthio-D, L-proline are cooled in ice under argon and cold, argon saturated mixture 7 is added thereto. ml of water and 7 ml of concentrated ammonia. After stirring at 0 ° C for 30 min, the solution was acidified with hydrochloric acid and the product was extracted with ethyl acetate. The extract is dried and the solvent is evaporated off under vacuum. 1.85 g of material are obtained, which crystallizes on standing. After trituration with ether, 1.0 g (57%) of a white crystalline product is obtained which, after recrystallization from 5 ml of ethyl acetate, yields 0.85 g of trans-1- (3-mercapto-1-oxopropyl) -3-methylthio-D, L-proline, m.p. 89-93 ° C.

Analysis for:

C9H15O3NS2:

calculated:

C: 43.35%, H: 6.06%, N: 5.62%,

S: 25.72%;

found:

C: 43.35%, H: 6.27%, N: 5.54%,

S: 25.91%.

Example 12 cis-4- (1,1-dimethylethoxy) -1- (D -3-mercapto-2-methyl-1-oxopropyl) -L-proline

(a) N-benzyloxycarbonyl-cis --- (1,1-dimethylethoxy) -L-proline methyl ester

A Parr autoclave is charged with a solution of 6.0 g (0.021 mol) of methyl ester of N-benzylooylcarbonyl-cis-4-hydroxy-L-proline in 60 ml of methylene chloride, cooled with a magnetic stirrer in a solid carbon dioxide bath in isopropyl alcohol. 40 ml of liquefied isobutylene and then 0.75 ml of concentrated sulfuric acid are introduced. The autoclave is sealed and the reaction mixture is allowed to warm to room temperature while stirring, with no measurable pressure rise. The reaction mixture was stirred at room temperature for 4 days, then the autoclave was opened, the reaction solution of 80 ml was diluted with 120 ml of methylene chloride and washed with a solution of 5 g of sodium hydrogen carbonate in 100 ml of water. The aqueous phase was extracted with 50 ml of methylene chloride, the organic layers were combined, dried over magnesium sulfate and the solvent was evaporated. It is obtained

7.5 g of N-benzyl-oxycarbonyl-c's-4 - (-, 1-dimethylthoxy) -L-pro] nine methyl ester in the form of a pale yellow oil having an optical rotation of [ab ²⁵ - = - ⁴⁶ ° (c - 1% in chloroform) ). TLC on silica gel had Rf = 0.62 (toluene) and Rf = 0.43 (benzene-acetic acid 7: 1). Detection is by iodine pairs and UV-radiation.

b) N-benzyloxycarbonyl-cis-4- [1,1-dimethylethoxy] -L-proline

A solution of 7.2 g (0.02 mol) of the methyl ester prepared in a) in 15 ml of ether was cooled in ice-water and 42 ml [0.042 mol) of ice-cold 1 N sodium hydroxide solution was added portionwise. The mixture was stirred under cooling for a total of 6 hours, then the cooling bath was removed and stirring was continued overnight at room temperature. The resulting clear solution was washed with 40 ml of ether (the washings were discarded), layered with 40 ml of ethyl acetate and acidified with 8 ml of 6 N hydrochloric acid with stirring and cooling. After separation the aqueous phase is extracted three times with '40 ml of ethyl acetate, the organic layers were combined, dried over magnesium sulfate and about ¹ rozpou.š'těd evaporated. 6.8 g of a light yellow viscous oil is obtained, which is dissolved in 50 ml of acetonitrile and a warm solution of 3.2 g of 1-adamantanamine in 20 ml of acetonitrile is added to the solution, whereupon a solid adamantanammonium salt precipitates rapidly. After cooling overnight, the colorless salt was filtered off under nitrogen, washed with cold acetonitrile and ether, and dried in vacuo. 8.8 g adamantamoniové salt of N-benzyloxycarbonyl-cis-4- (71-dimethyleíhoxy JL-proline, melting point 228-230 DEG C., optical ro-tation (a] ² 5 n - -28 ° ( c == 1% in methanol).

Analysis for:

C1.7H23NO5. C20H17N. 0,25 HO:

calculated:

С: 67.96%, H: 8.56%, N: 5.87%;

found:

С: 67.77%, H: 8.54%, N: 5.93%.

Treatment of the acid with 8.5 g of the above-mentioned adamantanammonium salt afforded 5.5 g of N-benzyloxycarbonyl-cis-4- (1,1-dimethylethoxy) -L-proline as an almost colorless viscous syrup which was subjected to thin layer chromatography on silica gel. in a toluene-acetic acid (85: 15) system, it has an Rf of 0.20 (iodine vapor or phosphomolybdic acid detection and heating).

c) cis -4- (7,7-dimethylethoxy) -L-proline

5.5 g (0.017 mol) of the N-benzyloxycarbonylderivative prepared in b) are hydrogenated in 165 ml of a 2: 7 mixture of methanol and water under a hydrogen pressure of 0.3 MPa in the presence of 1.7 g of 5% palladium on carbon catalyst. . 3.2 g of a sticky, partially solid product are obtained. This material was suspended in 30 mL of acetonitrile and cooled after trituration overnight. 1.35 g of cis-4- (1,1-dimethylethoxy) -L-poline are obtained in the form of a colorless solid, melting with decomposition at 24 DEG to 242 DEG C., the melting being preceded by darkening and sintering. [α] ²⁵ D = -36 ° (c == 0.5% in methanol).

Analysis' for:

C9Hi7NO3.0,25 IfeO:

calculated:

С: 56.37%, H: 9.20%, N: 7.31%;

found ¹ :

С: 56.26%, II: 9.27%, N: 7.26%.

d) 1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -cis-4- (1,7-dimethylethoxy) -L-proline

In analogy to Example 3, 1.3 g (0.0069 mol) of cis-4- (7,7-dimethylethoxy) -L-proline from c) were reacted with 1.4 g (0.0078 mol) of D 3-acetylthio-2-methylpropionyl chloride in 20 mL of water in the presence of sodium bicarbonate. 2.2 g of an almost colorless viscous oil are obtained. This crude product was dissolved in 50 ml of ethyl acetate and 1.3 g of dicyclohexylamine in 20 ml of ethyl acetate was added to the solution. The product crystallized from the reaction solution was filtered off and dried. 2.65 g of dicyclohexylammonium salt of melting point 181 DEG-183 DEG C. (sintered from 170 DEG C.) with an optical rotation of [ _.alpha. ] _D @ 25 = -62 DEG (c = 1% in ethanol) are obtained. Trituration of this material with 15 ml of hot acetonitrile followed by quenching gave 2.4 g of a colorless solid dicyclohexylammonium salt, m.p. 183-185 ° C (sintered from 175 ° C), with an optical rotation ()) d ²⁵ = - -65 ^o ( c = 1 in ethanol).

Analysis for:

C75H25NO5S. C12H23N:

calculated:

С: 63.24%, H: 9.44%, N: 5.46%,

S: 6.25%;

found:

С: 63.22%, H; 9.61%. N: 5.41%,

S: 6.02%.

Using the procedure described in Example 3, 2.4 g of this dicyclohexylammonium salt is converted to the free acid by suspending the salt in ethyl acetate and adding 30 ml of 10% sodium hydrogen sulphate solution while cooling in ice. The layers were separated and the aqueous phase was extracted four times with 25 ml of ethyl acetate each time. After evaporation of the solvent, the residue, which on standing, partially crystallizes, is triturated under 10 ml of ether to complete crystallization, then the mixture is diluted with 20 ml of hexane and cooled after trituration. 1.3 g of 7- (3-3- (acetylthio) -4- (4-methyl-1-oxopropyl) cis-4- (7,1-dimethylethoxy) -L-proline are obtained. in the form of a colorless solid, m.p. 96-98 ° C (sintered from 93 ° C), optical rotation [α] _D ²⁵ = -109 ° (c = 1% in ethanol).

Analysis for:

CisHžsNOjS:

calculated:

C: 54.36%, H: 7.60%, N: 4.23%,

S: 9.68%.

found:

C: 53.92%, H: 7.73%, N: 4.30%,

S: 9.29%.

e) cis-4- (1,1-dimethylethoxy) -1- (D -3-mercapto-2-methyl-1-oxopropyl) -L-proline

1.3 g (0.0039 mol) of 1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -cis-4- (1,1-dimethylethoxy) -L-proline of part d) are hydrolyzed 2.6 ml of concentrated ammonium hydroxide in 6 ml of water, yielding 1.1 g of a glassy residue in which seed crystals appear on standing, this product is overlaid with 8 ml of ether, seeded and triturated. After 2 hours at room temperature, 20 ml of hexane were added and the mixture was cooled under argon overnight. After evaporation of the solvent, 1.0 g of colorless solid cis-4- (1.1 g) was obtained. -dimethylethoxy) -1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-proline, m.p. 106 DEG-108 DEG C., optical rotation [ _.alpha .] _D @ 25 = -78 DEG (c) - 1% in ethanol).

Analysis for:

C15H23N4S. 0,25 H2O:

calculated:

C: 53.12%, H: 8.06%, N: 4.77%,

S: 10.91%;

found:

C: 53.30%, H: 8.28%, N: 4.76%,

S: 10.70 θ / о.

Example 13

Cis-4 - [(4-Fluorophenyl) thio] -1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-p.LO-line salt with L-arginine - (1: 1)

a) Trans --- [D-3- (benzoylthio) -2-methyl-1-oxopropyl] -4-hydroxy-L-proline methyl ester

Dissolve 56.05 g (0.25 mol) of D-3- (benzo-ШORЗ-methylpropanoic acid) in

62.5 ml toluene. The temperature is lowered to 15 ° C, 0.386 ml of dimethylformamide is added to the suspension, and then 32.7 g (0.25 mol of 4- 10% excess) of thionyl chloride are added in a single portion. The temperature of the reaction mixture is lowered to 12 ° C, the vessel used for measuring thionyl chloride is rinsed with 21.2 ml of toluene, which is added to the reaction mixture, the temperature of which is gradually raised to 35 ° C and kept at this temperature for 1 hour. The resulting mixture was stirred at room temperature overnight, then the solvent and excess thionyl chloride were distilled off, the residue was stirred twice with 100 ml of toluene and the toluene was evaporated. 63.4 g of D-3- (benzoylthio) -2-methylpropanoic acid chloride are obtained.

32.7 g (0.25 mol) of L-4-hydroxy-proline are dissolved in 250 ml of water at pH 5.8, and the pH is adjusted to 9.3 by the addition of approximately 60 ml of 10% sodium carbonate and the solution is heated to 30 ° C. 75 ml of a toluene solution containing 63 g of D-3- (benzoylthio) -2-methylpropanoic acid chloride and a 10% solution of sodium carbonate in water are simultaneously added over 1 hour at 30 DEG C. and maintaining the pH at 9.0. The resulting solution was stirred at pH 9 for 1.5 hours, then the toluene layer was separated and the aqueous layer was strongly acidified with concentrated hydrochloric acid.The crystalline solid material was filtered off, washed with water and air dried to give 71.4 g. 195 DEG-196 DEG C. traDS-1- [D-3- (benzoylthio-2-methyl-1-oxopropyl-1-hydroxy-L-proline), m.p. 195-196 DEG C. After recrystallization from alcohol, the melting point was increased to 196-197. DEG. The product has - «] d ²⁵ = -139 - DEG (c = 1%, methanol).

Analysis for:

C16H19NO0S:

calculated:

N: 4.15%, C: 56.95%, H: 5.67%,

S: 9.50%;

found:

N; 3.96%, C: 56.56%, H: 5.77%,

S: 9.50%.

The solution - - 33.7 g (0.1 mo ¹⁾ trans - l- [D-3- (benzoy.lthio ·) -2-methyl-N-oxopropyl] -4 - hydroxy-L-.prolinu and 500 mg of p -toluenesulfonic acid in 1 liter of methanol is gently refluxed for about 18 hours. Evaporation of the methanol yielded 37 g of a viscous residue which was dissolved in 1400 ml of ether. The ethereal solution was washed twice with 250 ml of water, twice with 250 ml of 5% sodium bicarbonate solution and once with 250 ml of brine, dried over magnesium sulfate and the ether was evaporated. Trituration with petroleum ether gave 27.3 g of crystalline product, m.p. 64-65 ° C. This product, after recrystallization from ether, yields trans-1- [D-3- (benzoylthio) -2-methyl-4-hydroxy-4-hydroxy-4-hydroxy-methyl ester, m.p. optical rotation [α] ²⁵ D -158 ° (c = -1%, methanol).

Analysis for:

C17H21NO5S:

calculated:

C: 58.10%, II: 6.02%, N: 3.99%,

S: 9.12 0 / _o; found:

C: 57.96%, II: 6.09%, N: 3.96%,

S: 9.11 0/0.

b) N- (p-fluorophenylthio) succinimide

Using the procedure described by Y. Abe et al. in Bull. Chem. Soc. Japan, Vol. 46, p. 1898 (1973), a suspension of 12.1 g (90.8 mmol) of N-chlorosuccinimide in 500 ml of benzene under nitrogen is treated with a solution of 9.7 g (75.7 mmol) of p-fluorothiophenol in 90 ml of benzene. A slight increase in temperature occurred and the reaction mixture turned yellow-orange. After 75 minutes, the solution was cooled to 15 ° C and 9.19 g (90.8 mmol) of triethylamine in 90 ml of benzene was added over 25 minutes. The cooling bath was removed, the reaction mixture was stirred for 45 minutes, then filtered, the organic solution was washed three times with 150 ml of water each, brine, dried over magnesium sulfate and the solvents evaporated in vacuo. 15.8 g of crude product are obtained, which, after recrystallization from a mixture of chloroform and hexane, gives 11.6 g of N- (p-fluorophenylthio) succinimide, m.p. 130-138 ° C.

c) cis-1- [D-3- (Benzoylthio) 2-methyl-1-oxopropyl] -4 - [(4-fluorophenyl) thio] -L-proline methyl ester

To a solution of N- (p-fluorophenylthio) succinimide (11.0 g, 48.8 mmol) in benzene (200 mL) was added tri-n-butylphosphine (9.87 g, 48.8 mmol) in benzene (25 mL) under a nitrogen atmosphere. The solution was stirred at room temperature for 10 minutes, then treated with 15.6 g (44.4 mmol) of trans-1- [D-3- (benzoylthio) -2-methyl-1-oxopropyl] -4- methyl ester. The reaction mixture is stirred at room temperature overnight, diluted with 200 ml of ether, washed four times with 75 ml of water each, brine, dried over magnesium sulfate and the solvent is evaporated off under vacuum.

32.6 g of crude product, which is adsorbed onto about 70 g of silica gel and chromatographed on a column of 450 g of silica gel prepared in a mixture of equal parts of diethyl ether and hexane. The column is eluted first with two liters of a mixture of equal parts of diethyl ether and hexane and then with two liters of a 2: 1 mixture of diethyl ether and hexane and finally with ether alone. The best fractions containing the product were combined and evaporated to give 16.7 g of cis-1- [D-3- [benzoylthio) -Z-methyl-4-oxo-propyl-4 - [(4-fluorophenyl) thio] methyl ester. ] -L-proliuu as an oil opťcké rotation [<s _[r / 25 = -30.2 ° (c - = - 1%, chloroform).

d] cis-4 - [(4-fluorophenyl) thio] -1- (D-3-mercapto-2-methyl-1-oxorropyl) -L-proline salt with L-arginine (1: 1)

A solution of 15.7 g (34.0 mmol) of cis-1- [D-3- (beuzoylthi) -2-methyl-1-oxopropyl] -4 - [(4-fluorophenyl) thio] -L-proline methyl ester in a mixture 50 ml of methanol and 150 ml of tetrahydrofuran were cooled in ice under nitrogen and 71.4 ml of 1 N aqueous sodium hydroxide solution were added over 10 minutes to this cold solution. Remove the cooling bath, stir the reaction at room temperature for 5.5 hours, then dilute with 300 mL of water and wash three times with 200 mL of ether each time. The aqueous layer was cooled in ice under nitrogen, acidified with concentrated aqueous hydrochloric acid to pH 1-2 and extracted with ether (3 x 200 mL). The combined organic extracts were washed first with 200 ml of water, then with brine, dried over magnesium sulfate and the solvent was evaporated in vacuo to give 11.7 g of crude product which was dissolved in ether and treated with methanolic solution 5.66 g. (37.4 mmol) of 1-adamantanamine After dilution with ether, 15.2 g of the adamantanammonium salt is obtained, which is recrystallized by dissolving in a mixture of equal parts of chloroform and methanol, and then diluting with ether. 3 g of adamantanammonium salt melting at 238 DEG-240 DEG C. decomposed after further two crystallizations from the chloroform-methanol-ether solvent system.

10.6 g of cis-4 - [(4-fluorophenyl) th adamantanammonium salt ^; o] -1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-proline, m.p. 242 DEG-243 DEG C. (decomposition) and optical rotation [.alpha.] D @ ²⁵ = -51.13 DEG (c = 0.5%, methanol).

A sample of this adamantanammonium salt was extracted with ethyl acetate from 1 N aqueous hydrochloric acid to give cis-4 - [(4-fluorophenyl) thio-] -1- (D-3-mercapto-2-methyl-1-oxopropyl) -L- proline optical rotation [a] D = ² 5 -42.5 ° (c = 1% in absolute ethanol).

To a vigorously stirred mixture of 20 ml of 1N hydrochloric acid, 40 ml of water and 60 ml of ethyl acetate was added portionwise 8.0 g (16.2 mmol) of the adamantanamine salt of cis-4 - [(4-fluorophenyl) thio-) - 1- (D-3-mercapto-2-methyl-1-oxopropyl) -1-proline This procedure was carried out under nitrogen with cooling in ice, and the aqueous layer was extracted twice more with 60 ml of ethyl acetate each time and the combined organic extracts were washed Dilute aqueous hydrochloric acid, water and brine, dried over magnesium sulfate

The solvent was evaporated in vacuo. 5.78 g of the liberated acid are obtained in the form of a crude oil which is dissolved in a mixture of 40 ml of ethyl acetate and 10 ml of ether. The solution is shaken in a separatory funnel with a solution of 2.68 g (15.4 mmol) of L-arginine in 50 ml of water, the aqueous layer is washed again with ether, evaporated on a rotary evaporator under low pressure for 15 minutes and then lyophilized overnight. . 7.97 g of the salt of cis-4 - [(4-fluorophenyl) thiol] -1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-propene with L-arginine (1: 1) are obtained. optical rotation [.alpha.] D @ ²⁵ = -42.7 DEG (c = 1%, water).

Analysis for:

CuHuFNOjSs. C6H14N4O2:

calculated:

C: 47.08%, H: 6.40%, N: 13.08%,

S: 11.97%, F: 3.55%, SH: 6.17%;

found:

C: 47.21%, H: 6.74%, N: 13.28%,

S: 11.71%, F: 3.38%, SH: 5.98%.

Example 14

Cis-4- (4-chlorophenyl) thlo] -1- (D-3-mercapio-2-methyl-1-oxopropyl) -L-proline salt with L-arginine (1: 1)

a) N- (p-chlorophenylthio) sncininide analogously to Y. Aba et al. (see above), to 4.3 g (33.2 mmol) of N-chlorosuccinimide and 1800 ml of benzene was added a solution of 40.0 g (27.7 mmol) of p-chlorothiolenol in 360 ml of benzene. After 1 hour, the resulting orange-colored solution was cooled to 15 ° C and 33.6 g (33.2 mmol) of triethylamine in 360 ml of benzene was added over 15 minutes. Remove the cooling bath and stir the reaction mixture at room temperature for a further 45 minutes. The resulting mixture is filtered, the organic phase is washed three times with 500 ml of water, 500 ml of brine, dried over magnesium sulfate and the solvent is evaporated off under vacuum. 55.1 g of crude product are obtained, which trituration with 900 ml of petroleum ether gives 42.0 g of N- (p-chlorophenylthio) succinimide, m.p. 135-152 ° C.

b) cis-1- [D-3- (Benzoylthio) -2-methyl-1-oxopropyl] -4 - [(4-chlorophenyl) thio] -L-proline methyl ester

To a solution of 15.1 g (62.3 mmol) of N- (p-chlorophenylthio) succinimide in 250 mL of benzene was added a solution of 12.6 g (62.3 mmol) of tri-n-butylphosphine under nitrogen at room temperature. in 25 ml benzene. After 10 minutes, 20 g (56.9 mmol) of methyl 1 'and 5'-1- [D-3- (benzoylthio) -1-methyl-1-oxopropyl] -4-hydroxy-L-proline methyl ester are added and the reaction is carried out. The reaction mixture was diluted with 300 ml of ether, washed four times with 100 ml of water each, brine, dried (MgSO4) and the solvent was evaporated in vacuo to give 46 g of crude material, which was evaporated to dryness. adsorbed to about 75 g of silica gel and chromatographed on a column of 450 g of silica gel, the column was prepared in ether and eluted with ether, and the product containing fractions were combined and evaporated to give 27.2 g of product, 48 g is flash chromatographed on 25 g of silica (EM9385) This column is prepared in methylene chloride and eluted first with methylene chloride and then with methylene chloride / ethyl acetate 18: 1 to give 0.28 g of cis-1- [D] methyl ester. -3- (benzoylthio) • 2-methyl-1-oxopropyl) -4 - [(4-chloro) -benzyl Phenyl) thio] -L-proline with optical rotation [α] _D 25 = -86.6 ° (c = 1%, chloroform).

c) cis-4 - [(4-chlorophenyl) -1- (D-3-mercapto-2-methyl-1-oxopropyl) -L-proline salt with L-arginium (1: 1)

A solution of 24.3 g (50.8 mmol) of cis-1- [D-3- (benzoylthio) -2-methyl-1-oxopropyl] -4 - [[4-chlorophenyl] thio] · L-proline methyl ester in A mixture of 80 ml of methanol and 220 ml of tetrahydrofuran was cooled in ice under nitrogen and 106 ml of 1 N aqueous sodium hydroxide solution were added over 10 minutes. The cooling bath was removed and the reaction mixture was stirred at room temperature for 5.5 hours. The reaction solution was diluted with 500 ml of water and washed three times with 300 ml of ether each time, the aqueous solution was cooled under nitrogen in ice and concentrated hydrochloric acid, acidified to pH 1-2. The mixture was extracted three times with 500 ml of ether each time. washed with 400 ml of water and brine, dried over magnesium sulfate and concentrated in vacuo to give 18.2 g of a crude product which was dissolved in ether and treated with methanolic solution of 8.5 g (55.9 mmol). The mixture was diluted with ether to a volume of about 1 liter for 1.5 hours The mixture was cooled in a refrigerator and then filtered to give 20.1 g of the adamantanammonium salt, m.p. 239-242 ° C. This material was dissolved in a mixture of equal parts of chloroform and methanol and diluted with ether to give 15.3 g of cis-4 - [(4-chlorophenyl) thio] -1- (D-3-mercapto) 1-adamantanammonium salt. -mnthylι -2 - oxopropyl) -L-proline, m.p. 240-241 C (dec) optical rotation [a / r ⁵ - -55, -4 ° (c-0.5% methanol).

A small sample of this adamantanammonium salt (0.5 g; 0.98 mmol) was partitioned between aqueous hydrochloric acid and ethyl acetate to give the corresponding free acid with an optical rotation of [α] D = -38.1 ° (c - 1%, absolute) ethanol).

To a vigorously stirred mixture of 18.8 mL of 1 N aqueous hydrochloric acid, 3030 mL of water and 50 mL of ethyl acetate was added portionwise 8 g (15.6 mmol) of the adamantanammonium salt prepared above. The solution is cooled in ice and kept under a nitrogen atmosphere. After all solids had dissolved, the aqueous layer was extracted twice with 50 ml of ethyl acetate each time, the organic extracts were combined / washed with 30 ml of 0.5 N aqueous hydrochloric acid, 30 ml of water and finally with brine. The solution was dried (MgSO 4) and concentrated in vacuo to give 5.6 g of the liberated acid. This acid was dissolved in a mixture of 50 mL of ethyl acetate and 15 mL of ether and shaken with a solution of 2.57 g (14.8 mmol) of L-arginine in 65 mL of water. The aqueous layer was washed with ether (50 mL) and lyophilized overnight. 8.0 g of cis-4 - [(4-chlorophenyl) thio] -1- (D-3-mercapto-2-methyl-oxopropyl) -L-proline salt with L-arginine (1: 1) are obtained, m.p. optical rotation [α] _D ²⁵ = -44.3 degrees (с 1 ° / o, water).

Analysis for:

C15H18CINO5S2. CsHnNdOj:

calculated:

C: 45.09%, H: 6.27 θ / ο, N: 12.52%,

S: 11.46%, Cl: 6.34%, SH: 5.91%;

found:

C: 45.34 0/0, Η: 6.34%, N: 12.57%,

S: 11.48%, Cl: 6.12%, SH: 5.44%.

Example 15

Cis-1- (D-2-mercapto-2-methyl-loxopropyl) -4 - [(4-methylphenyl) thio] -L-proline salt with L-arginine (1: 1)

a) cis 1- [D-3- (Benzoylthio) -2-methyl-1-oxopropyl] -4 - [(4-methylphenyl) thio] -L-proline methyl ester

To a solution of 20 g (56.8 mmol) of trans-1- [D-3- (benzoylthio) -2-methyl-1-oxopropyl] -4-hydroxy-L-proline methyl ester and 15.4 g (62.5 mmol) of p-tolyldisulfide in 120 ml of benzene was added a solution of 12.6 g (62.5 mmol) of tri-butylphosphine in 20 ml of benzene over 5 minutes under nitrogen at room temperature. The reaction mixture is allowed to stand overnight, then diluted with 300 ml of diethyl ether, the organic solution is washed three times with 100 ml of water each and brine, dried over magnesium sulphate and concentrated in vacuo. 49 g of crude product are obtained. This material is adsorbed onto 75 g of silica gel and applied to a 450 grams silica gel column prepared in a mixture of equal parts of hexane and ether. The column is eluted first with a mixture of equal portions of hexane and ether (3 liters), then with 2 liters of a 2: 1 mixture of ether and hexane and finally with pure ether. The best fractions containing the product were combined to give 14.6 g of cis-1- [D-3- (benzoylthio) 2-methyl-1-oxopropyl] methyl ester | 4 - [(4-methylphenyl) thio] -L-proline. A small sample of this material was flash chromatographed on silica gel (EM9385) eluting with methylene chloride / ethyl acetate. The product thus purified has an optical rotation [.alpha.] D @ ²⁵ = -70.8 DEG (c = 1%, chloroform).

b) cis-1- (D-3-mercapto-2-methyl-1-oxopropyl) -4 - [(4-methylphenyl) thio] 1-L-proline salt with L-arginine (1: 1)

To an ice-cooled solution of 13.0 g (28.4 mmol) of methyl ester of cis-1- [D-3- (benzoylthio) -2-methyl-1-oxopropyl] -4 - [(4-methylphenyl) thio] -L-proline in a mixture of 40 ml of methanol and 130 ml of tetrahydrofuran, 59.6 ml of 1 N aqueous sodium hydroxide solution are added over 10 minutes under continuous nitrogen flow, after which the cooling bath is removed and the reaction mixture is stirred at room temperature under nitrogen for 5.5 hours. The reaction mixture was diluted with 250 ml of water and washed twice with 200 ml of ether each time, the aqueous layer was cooled under nitrogen in ice, acidified to pH 1-2 with concentrated hydrochloric acid and extracted three times with 200 ml of ether each time. ml of water and brine, dried over magnesium sulphate and concentrated in vacuo to give 10.6 g of a colorless oily product which was almost uniform according to thin layer chromatography, which was dissolved in ether and as a gum. a solution of 4.72 g (31.2 mmol) of 1-aclamantanamine in 20 ml of methanol is added thereto. Precipitation precipitated rapidly, the mixture was diluted with ether to a total volume of about 700 ml and the salt was filtered off. After trituration with a warm mixture of methanol and ether, 12.4 g of the adamantanammonium salt melting at 237 DEG-240 DEG C. decomposes. This salt is recrystallized by dissolving in a minimum amount of a mixture of equal parts of chloroform and methanol, and diluting the solution with ether. After standing for 10 min at room temperature, the solid product was filtered off and dried. 8.2 g of the adamantanammonium salt are obtained, m.p. 240 DEG-241 DEG C. (decomposition) with an optical rotation of [.alpha.] D @ ²⁵ = -58.0 DEG (c = 0.5 DEG / o, methanol).

A small sample of this adamantanammonium salt was partitioned between aqueous hydrochloric acid and ethyl acetate to give cis-1- (D-3-mercapto-2-methyl-11-oxopropyl-4 - [(4-methylphenyl) thio] -1-proline in the form of an oil with optical rotation [α] _υ ²⁵ = -45,1 ° c = 1%, absolute ethanol).

To a mixture of 17.1 ml of 1N aqueous hydrochloric acid, 30 ml of water and 50 ml of ethyl acetate was added in several portions 7.0 g (14.3 mmol) of the above-prepared adarnantanammonium salt. During the addition, the solution is cooled in ice and kept in an argon atmosphere. After all the salt had dissolved, the layers were separated, the aqueous layer was extracted twice more with 50 ml of ethyl acetate each time and the extracts were combined with the ethyl acetate layer. The organic phase was washed with dilute hydrochloric acid, water and brine, dried over magnesium sulfate and concentrated in vacuo to give the free acid which was dissolved in a mixture of 40 mL of ethyl acetate and 10 mL of ether. The solution was shaken with a solution of 2.37 g (13.6 mmol) of L-arginine in 50 mL of water, the aqueous layer was washed with 50 mL of ether and lyophilized. There was obtained the salt of c ^: sl- (D-3-mercapto-2-methyl-1-oxopropyl) -4 - ((4-methylphenyl) thio] -L-proline and L-arginine (1: 1) with optical rotation [.alpha.] D @ ²⁵ = -45.3 DEG (c = 1%, water).

Analysis for:

CiGH21NChS2. C3H1N1O2:

calculated:

C: 49.69%, H: 7.01 ° / o, N: 13.17%,

S: 12.06%, SH: 6.22%;

found:

C: 49.55%, H: 7.04%, N: 13.28%, S: 11.73%, SH: 5.97%.

Example 16

Cis-1- (D-3-mercapto-2-methyl-1-oxopropyl) -4 - [(4-methoxyphenyl) thiol-L-proline salt with L-arginine (1: 1)

a) N- (p-methoxyphenylthio) succinimide

To a mixture of 17.1 g (128 mmol) of N-chlorosuccinimide and 700 ml of benzene was added a solution of 15 g (107 mmol) of p-methoxythiophenol in 125 ml of benzene. After 75 minutes, the resulting orange colored solution was cooled to 15 ° C and 13.0 g (128 mmol) of triethylamine in 125 ml of benzene was added over 25 minutes. Remove the cooling bath, stir the reaction mixture at room temperature for an additional 45 minutes, then filter. the organic solution was washed with water (3 x 200 ml) and brine (200 ml), dried (MgSO4) and the solvent evaporated in vacuo. 27.0 g of crude product are obtained, which, after recrystallization from chloroform-hexane, gives 21.2 g of N- (p-methoxyphenyl) succinimide, m.p. 100-106 ° C.

b) cis-1- [D-3- (Benzoylthio) -2-methyl-1-oxopropyl-1-4 - ((4-methoxyphenyl) thiol-L-proline) methyl ester

12.0 g (59.1 mmol) of tri-n-butylphosphine dissolved in 25 ml of benzene are added to a solution of 14.0 g (59.1 mmol) of N- (p-methyloxyphenylthio) succinimide in 250 ml of benzene at room temperature under nitrogen. After 10 minutes, 18.9 g (53.7 mmol) of trans-1- [D - 3- (benzoylthio) -2-methyl-1-oxopropyl] -4-hydroxy-L-proline methyl ester was added, the reaction mixture was stirred for 18 min. The mixture was allowed to stand at room temperature under nitrogen for 25 hours, then diluted with 300 ml of ether, washed three times with 100 ml of water and brine, dried (MgSO4) and the solvent evaporated in vacuo to give 40 g of crude material which was adsorbed. 80 g of silica gel and chromatographed on a 450 g silica gel column, prepared in hexane / ether (4: 1), eluting first with hexane / ether (2: 1) and then with hexane: The best fractions containing the product were combined to give 20.6 g of product sample of this material (0.5 g) was further purified by flash chromatography on 50 g of silica (EM9385), the column was prepared in ether and the ether are also eluted. From the combined best product-containing fractions, 480 mg of cis-1- [D-3- (benzoylthio) -2-methyl-1-oxopropyl] -4 - [(4-methoxyphenyl) thio] -L-proline methyl ester is obtained. rotation [α] _D ²⁵ = 66.9 ° (c = -1, chloroform).

c) cis-1- (D-3-mercapto-2-methyl-1-oxo-propyl) -4 - [(4-methoxyphenyl) thio] -L-proline salt with L-arginine (1: 1)

A solution of 20.1 g (42.4 mmol) of cis-1- [D 3 (benzoylthio) -2-methyl-1-oxopropyl] -4 - [(4-methoxyphenyl) thio] 1-L-proline methyl ester in a mixture of 70 ml of methanol and 200 ml of telrahydrofuran was cooled in nitrogen under nitrogen and 89 ml of 1 N aqueous sodium hydroxide was added over 10 minutes. The cooling bath was separated, the reaction mixture was stirred at room temperature for 5.5 hours, then diluted with 500 ml of water and washed three times with 300 ml of ether each time. The aqueous solution was cooled in poison under nitrogen, acidified with concentrated hydrochloric acid to pH 1 and extracted three times with 500 ml of ether each time. The combined ether extracts were washed with water (400 mL) and brine, dried (MgSO 4) and concentrated in vacuo. 14.8 g of crude product are obtained, which is dissolved in ether and a solution of 6.34 g (42 mmol) of 1-adamantanamine in methanol is added to this solution. The mixture is diluted with ether to a volume of about 1 liter, allowed to stand at room temperature for 10 minutes and filtered. 17.8 g of adamantanammonium salt are obtained, melting at 235-236 ° C with decomposition. This material was dissolved in a mixture of equal parts of chloroform and methanol under gentle heating and diluted with ether. This recrystallization is repeated two more times. 12.2 g of 1-adamantanammonium salt of cis-1- (D-3-mercapto-2-methyl-1-oxopropyl) -4 - [(4-methoxyphenyl) - is obtained.

2.2 nyi) thio-L-proline temperature. Melting · ·· 237 · 239 ° C (decomposition, optical rotation _[a] ²⁵ = - -52.8 ° (c - 0.5. %, methanol).

A small sample of this 1-adamantanammonium salt 500 mg; 0.99 mmol) was partitioned between aqueous hydrochloric acid · arethylacetát, to yield the corresponding free acid with an optical rotation [Ajo ²⁵ - -36.8 ° (c = 1% in absolute ethanol).

To a vigorously stirred mixture of 27.2 ml of 1 N aqueous hydrochloric acid, 45 ml of water and 75 ml of ethyl acetate are added in portions.

11.5 g (22.7 mmol) of the above obtained 1-adamantanamoniové · Sa · i, wherein - the solution is · .. • CH ¹ ADI ice and kept at ·, · nitrogen atmosphere. After dissolving all of the solid material, the aqueous layer is twice more. extract with 75 ml of ethyl acetate each time, the organic extracts are combined, washed with 50 ml of 0.5N aqueous hydrochloric acid, 50 ml of water and finally with sodium chloride solution. Resulting. The solution was dried (MgSO4) and concentrated in vacuo. 8.2 g of free acid are obtained, which is dissolved in a mixture of 75 ml of ethyl acetate and 20 ml of ether, and the solution is shaken with a solution of 3.76 g. 6 · mmol) · L · arginine in 100 ml water. The aqueous layer was washed with 75 ml of ether and lyophilized overnight. 11.2 g of a salt of cis- (D-3-mercapto-2-methyl-1-oxopropyl) -4 - ((4-methoxyphenyl) thio-1H-proline) with L-arginine (1: 1) are obtained. Optical rotation [° y ² 5 = - 46.0 ° (c · = 1 ·%, water).

Analysis for:

CysHiNOiSШ; 4N4O2:

calculated:

C: 47.93%, H: 6.84%, N: 12.70%,

S: 11.63%, SH: 6.00%;

found:

C: 47.99%, H: 6.61%, N: 12.66%,

S: 11.62%, SH: 6.00%.

Example 17 * cis-1- [D-3- (benzoylthio) -2-methyl-1-oxopropyl] -4- (phenylthio) -L-proline * 9.9 g · (0.031 mol) cis-4- The phenylthio-L-proline is suspended in 100 ml of water (pH 5.6) and the pH is adjusted to 10.2 by the addition of about 20 ml of 10% sodium bicarbonate solution, which makes the suspension a clear solution. The pH is then added approximately

4.5 ml of concentrated hydrochloric acid are adjusted to 9.5 and 8.1 g (0.033 mol) of D-3- (benzoylthio) chloride are added to the solution at 30 ° C. 2-methylpropanoic acid in 30 ml of toluene, together with 100 ml of 10% solution of sodium bicarbonate, to maintain the pH at 9.3. After the addition of about a quarter of the acid chloride is started

118 · mucous: · precipitate that persists in the mixture. throughout the reaction time. . The reaction mixture was stirred at pH 9.3 for 2.5 hours and then in the presence of ethyl acetate. The mixture was acidified by addition of 20% hydrochloric acid. The aqueous layer is extracted twice with 350 ml of ethyl acetate each time. The combined organic layers were washed with 300 ml of saturated sodium chloride solution and dried over magnesium sulfate. Evaporation of the solvent gave 11.8 g of crude product as a foamy solid.

Dissolve 11.8 g (0.027 mol) of this foamed solid in 70 ml of acetonitrile and add about 6 g of dicyclohexylamine in 25 ml of ether, immediately precipitating a white crystalline solid. The mixture was allowed to stand overnight in a cold room, then the solid product was filtered off and washed with ether. The salt of cis-1- [D-3- (benzoylthio) -2-methyl-1-oxopropyl] -4- (phenylthio) -L-proline with dicyclohexylamine (1: 1) was obtained.

Analysis for:

CžxHxsNOjSz. C12H23M:

calculated:

C: 66.85%, H: 7.59%, N: 4.59 ·%;

found:

’C: 66.33%, H: 7.30%, N: 4.48%.

The slightly damp dicyclohexylammonium salt is stirred for 2.5 hours. of a mixture of 300 ml of ethyl acetate and 200 ml of a 10% potassium hydrogen sulphate solution. Two clear layers were obtained. The aqueous layer was extracted twice with 200 ml of ethyl acetate each time, the combined organic layers were dried over magnesium sulfate. and · the solvent is. Evaporate · 10.1 g · Foam solid · cis-1- [D-3- (benzoylthio) -2-methyl-1-oxo-propyne-4- (phenylthio) -L-pr of melting point · 42 to 44. ° C o · optical: rotation [α] _D ²⁵ = == -36.5 0 · (c = · 1%, methanol).

Analysis for:

C22H23NO4S2:

calculated:

C: 60.87%, H: 5.46 ·%, N: 3.23%, found:

C: 60.75%, H: 5.35%, N: 3.17%.

Example 18

Cis-1- [D-3- [benzcylthio) -2-methyl-1-oxopropyl] -4- (phenylthio) -L-proline salt with L-arginine (1: 1)

To a solution of 2.3 g (0.0054 mol) of cis-1- [D-3-

- (Bmzoylthio) -2-methyl-1-oxopropyl] -4- (phenylthio-L-proline) in 100 ml of methanol was added 0.941 g (0.0054 mol) of L-arginine, resulting in a clear solution after stirring for about 10 minutes. After stirring at room temperature for about 5 hours, the solvent was evaporated and the solid residue was filtered with ether to give 2.5 g of the cis-1- salt.

- [D-3- (benzoylthio) · 2-methyl-1-oxopropyl] -4- (phenylthio) -L-proline with L-arginine (1: 1) which softens when heated at 105 ° C and decomposition melts at 110-112 ° C. The product has an optical rotation of [α] -25 = -278 ° (c = 1%, methanol).

Analysis for:

C22H22NO.1S2. C6H14N4O2:

calculated:

C: 54.88%, H: 6.25%, N: 11.43%,

S: 10.47%;

found:

C: 54.44%, H: 6.21%, N: 11.60%,

S: 10.40%.

Example 19

Cis-1- [D- (3-benzoyl-thio) -2-methyl-1-oxopropyl-4-piperidin] -L-proline sodium salt (1: 1)

A solution of 4.29 g (0.01 mol) of cis-1- [D-3- (benzoylthio) -2-methyl-1-oxopropyl] -4- (phenyl) -L-proline in 25 ml of methanol was added to the solution. 0.540 g (0.01 mol) of sodium methoxide in 25 ml of methanol. After adding about 50 ml of ether and stirring for about 10 minutes, a precipitate began to form. The mixture was allowed to stand overnight in a cold room, the gelatinous solid was filtered off, washed with ether and dried in a desiccator. 2.5 g of the sodium salt of cis-1- [D-3- (benzoylthio) -2-methyl-1-oxopropyl-4- (phenylthio) -L-proline (1: 1) are obtained. up to 220 degrees Celsius (decomposition) with optical rotation [α] _D 25 = -105.2 ° (c == 1%, water).

Analysis for:

C22H22NO4S2. On:

calculated:

C: 57.36%, H: 5.03%, N: 3.04%,

Na: 4.99%;

found:

C: 57.62%, H: 5.08%, N: 3.01%,

Na: 4.68%.

Example 20 cis-1- (η 3 -mercapto-2-methyl-1-oxopropyl) -3-phenoxy-D _;

a) 3-Phenoxy-1,2-dehydroproline tert-butyl ester

A mixture of 9.25 g (50 mmol) of ¹ tertbutyloxycarbonyl rsΐrru 1,2-yehodroprOlmu in 70 ml of toluene and 8.9 g (50 mmol) С-bromsukclnimidu 1 hour · heated to reflux under irradiation with a light bulb on a daily light located at a distance of about 5 cm. Succinimide is formed during this time. The reaction mixture was cooled to room temperature, the succinimide was filtered off and the filtrate was evaporated to dryness. Distillation of the residue at 80 ° C gave 3.5 g of crude 3-bromo-1,2-dehydroproline butyl ester.

A mixture of this crude 3-bromo-1H-dehydroproline tert-butyl ester and 3.9 g (13 mmol) of thallium phenoxide in 30 ml of dry dimethylformamide was stirred under argon at room temperature for 24 hours. The solvent was evaporated in vacuo and the residue was diluted with ether to precipitate thallium bromide, which was filtered off. Concentration of the filtrate yielded an oily material which was purified by distillation. After heating at 80 [deg.] C. for 2 hours at a pressure of 0.67 Pa, 1.48 g of 3-phenoxy-1,1-ethyl-proproline are left in a 1-liter flask.

b) cis-3-phenoxy-D, Lproline

A mixture of 1.48 g of 3-phenoxy-1,2-ethyl-propyl-butyl ester tert-butyl ester _? 5 ml of 1 N sodium hydroxide and 20 ml of 80% aqueous dioxane are stirred at room temperature for 4 hours, then the solvent is evaporated off under vacuum, the residue is dissolved in 25 ml of water and 168 mg of sodium borohydride are added at room temperature over 1 hour. The resulting mixture was acidified to pH 6 with 2 N hydrochloric acid, and the reaction solution was cooled to 0 ° C for 16 hours, whereupon about 25 mg of crystalline trans-3-phenoxy-D, L-proline precipitated. These crystals were filtered off and the filtrate was desalted on a Dowex 50 Wx8 ion exchange column (2.5 x 30 cm) using 1 N ammonium hydroxide as eluent. The UV-active fractions were combined and concentrated to give 616 mg of solid cis-3-frnoxy-D, L-proline.

c) cis-1- [D-3- (acetylthio) -2-methyl-1-oxopropyl-3-phenoxy-D, L-proline

616 mg of cis-3-phenoxy-D, L-propene at 5 ° C are suspended in 20 ml of water and the pH is adjusted to 8.0 with solid sodium carbonate. A solution of 550 mg (2.5 mmol) of D-3-acerylthio-2-methylpropanoic acid chloride in 1 ml of ether is added and the pH of the reaction mixture is maintained between 7.3 and 8 for 1.5 hours by addition of sodium carbonate. 2. The resulting mixture was washed with ethyl acetate (2.times.20 ml), acidified to pH 2 with 10% hydrochloric acid and extracted with ethyl acetate (3.times.50 ml). The extracts were combined, dried (MgSO4) and concentrated. 810 mg of an oily material are obtained, which is purified by flash chromatography on 300 ml of silica gel, eluting with toluene / 10-20% acetic acid. 530 mg of cis 1- [D-3- (acetylthio) -2-methyl-1-oxopropyl] -3-phenoxy-D, L-proline are obtained.

d) cis-1 (D-3-mercapto-2-methyl-1-oxopropyl) -3-phenoxy-D, L-proline

530 mg of cis-l- [D-3- (acetylthio] ^{-2-methyl-1-oxopropyl]} -3-phenoxy-D, L-proline was dissolved under argon in a mixture of equal parts of concentrated ammonium hydroxide and water? (Depleted The solution was acidified to pH 6.5 with concentrated hydrochloric acid (slightly warmed) and extracted twice with 25 ml of methylene chloride each time. The extracts were combined and dried (MgSO4) and concentrated to give 410 mg of a glassy material which was crystallized by trituration with chloroform and the solid product was recrystallized from ethyl acetate / hexane to yield 261 mg of cis-1. -

(D-3-mercapto-2-methyl-1-oxopropyl) -3-phenoxy-D, L-proline, m.p. 134-155 ° C.

Analysis for:

C15H19NO4S:

calculated:

C: 58.23%, H: 6.19%, N: 4.53%,

S: 10.36%;

found:

C: 58.07%, H: 6.18%, N: 4.45%, S: 10.16%.

Example 21

From the ingredients listed below, 1000 tablets are prepared, each containing 100 mg of 1-

- (D-3-mercapto-1-oxopropyl) -trans-4-methoxy-L-proline in the form of the sodium salt.

component amount 1- (3-mercapto-1-oxopro-) sodium polyl) -trans-4-methoxy-L-pro linu 100 g cornstarch 50 g gelatine 7,5 g Avicel (microcrystalline cellulose) for) 25 g magnesium stearate 2.5 g

The sodium salt of 1- (D-3-mercapto-1-oxopropyl) -trans-4-methoxy-L-proline and corn starch are mixed with an aqueous gelatin solution, dried and comminuted to a fine powder which, after mixing with Avicel and magnesium stearate granulated. 1000 tablets, each containing 100 mg of active ingredient, are prepared from the granulate on a tablet press.

Example 22

Tablets are prepared as described in Example 21, each containing 200 mg of 1- (D-3'-mercapto-2-methyl-1-oxopropyl) -trans-4-methoxy-L-proline.

Example 23

1000 tablets are prepared from the ingredients below, each containing 200 mg of 1- (D-3-mercapto-2-methyl-1-oxopropyl) -cis-4-methoxy-L-proline sodium salt.

Ingredient amount 1- (D-3-mercapto-2-methyl-1-oxopropyl) -cis-4-methoxy-L-proline sodium salt 50g lactose 25g

Avicel 38g corn starch 15g magnesium stearate 2g

The sodium salt of 1- (D-3-mercapto-2-methyl-1-oxopropyl) -cis-4-methoxy-L-proline, lactose and Avicel are mixed, then corn starch is added to the mixture and finally magnesium stearate is added. 1000 tablets of 130 mg each containing 50 mg of active ingredient are compressed from the dry mixture on a tablet press. The tablets are then coated with a methylcellulose solution (Methocel E 15) containing yellow No. 6 as a colorant.

Example 24

The mixture of the ingredients listed below is filled into No. 2 gelatin capsules such that each capsule contains 100 mg of 1- (D-3-mercapto-2-methyl-1-oxopropyl) -cis-4-methoxy-L-proline sodium salt.

ingredient amount sodium 1- (D-3-mercapto-2-methyl-1-oxopropyl) -cis-4-methoxy-L-proline 100mg magnesium stearate 7mg lactose USP 193mg

Example 25

A solution for injection is prepared from the following ingredients as described below.

quantity component

trans-4-methoxy-1- (D-3-mercapto-2- -methyl-1-oxopropyl) -L- -proline 500 g methylparaben 5 g propylparaben 1 g « sodium chloride 25 g water for injections replenish 1 liter F I will invent the subject

Claims (1)

A process for the preparation of substituted proline mercaptoacyl derivatives of the general formula I RS-CHrCH-CO-N-C-COOR * ^L H (I) wherein the X-R 1 group is attached at the 3 or 4 position of the proline ring, X represents oxygen or sulfur, R represents a hydrogen atom or a (C1-C4) alkyl group, R 1 represents a C 1 -C 4 alkyl or phenyl group optionally substituted by a halogen atom, a methyl group or a methoxy group, R2 represents a hydrogen atom or an alkyl group having 1 to 7 carbon atoms; R 4 represents a hydrogen atom of a C 1 -C 4 alkanoyl group or a benzoyl group and their base salts, characterized in that the proilin derivative of the general formula II The active substance, preservatives and sodium chloride are dissolved in 3 µl of water for injection and the solution is made up to a volume of 5 liters. The solution is filtered through a sterile filter and aseptically filled into pre-sterilized vials which are sealed with sterilized rubber closures. Each vial contains 5 ml of solution for injection at a concentration of 100 mg of active substance in each ml of solution. As in Examples 21 to 25, the products of all of the Examples can be formulated into dosage forms. in which R, R 1 and X are as defined above, condensed with an acid of formula III R2 Rf = S-CH2-CH-COOH (III) in which R2 is as defined above and Rd 'represents a C1 -C4 alkanoyl group or a benzoyl group, which condensation is carried out in the presence of a condensing agent such as dicyclohexylcarbodiimide or by using an activated form of the acid of formula III as the anhydride or halide of the acid, wherein R 1 is C 1 -C 4 alkanoyl or benzoyl and the remaining radicals are as defined above, optionally hydrolyzed to the corresponding product of formula I wherein R a is hydrogen and the remaining radicals are as defined above, and optionally converting the resulting product into its base salt.