[go: up one dir, main page]

WO2012117410A1 - A process for the preparation of n-[2-[(acetylthio) methyl]-1-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof - Google Patents

A process for the preparation of n-[2-[(acetylthio) methyl]-1-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof Download PDF

Info

Publication number
WO2012117410A1
WO2012117410A1 PCT/IN2011/000132 IN2011000132W WO2012117410A1 WO 2012117410 A1 WO2012117410 A1 WO 2012117410A1 IN 2011000132 W IN2011000132 W IN 2011000132W WO 2012117410 A1 WO2012117410 A1 WO 2012117410A1
Authority
WO
WIPO (PCT)
Prior art keywords
formula
compound
preparation
racecadotril
mole
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/IN2011/000132
Other languages
French (fr)
Inventor
Dodda Mohan Rao
Pingili Krishna Reddy
Tarnikanti PRAKASH
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Symed Labs Ltd
Original Assignee
Symed Labs Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Symed Labs Ltd filed Critical Symed Labs Ltd
Priority to PCT/IN2011/000132 priority Critical patent/WO2012117410A1/en
Publication of WO2012117410A1 publication Critical patent/WO2012117410A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00Medicinal preparations containing organic active ingredients
    • A61K31/21Esters, e.g. nitroglycerine, selenocyanates
    • A61K31/215Esters, e.g. nitroglycerine, selenocyanates of carboxylic acids
    • A61K31/22Esters, e.g. nitroglycerine, selenocyanates of carboxylic acids of acyclic acids, e.g. pravastatin
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C231/00Preparation of carboxylic acid amides
    • C07C231/02Preparation of carboxylic acid amides from carboxylic acids or from esters, anhydrides, or halides thereof by reaction with ammonia or amines
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C327/00Thiocarboxylic acids
    • C07C327/20Esters of monothiocarboxylic acids
    • C07C327/32Esters of monothiocarboxylic acids having sulfur atoms of esterified thiocarboxyl groups bound to carbon atoms of hydrocarbon radicals substituted by carboxyl groups
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C68/00Preparation of esters of carbonic or haloformic acids
    • C07C68/02Preparation of esters of carbonic or haloformic acids from phosgene or haloformates

Definitions

  • the present invention relates to a process for the preparation of N-[2-[(acetylthio) methyl]- l-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof.
  • the present invention relates to a process for the preparation of intermediate compound 2-(benzyl acrylolyl amino) acetic acid benzyl ester.
  • Racecadotril is a neutral endopeptidase inhibitor used as antidiarrheal in the treatment of chronic cardiac insufficiency and is available under the brand names Hidrasec and Tiorfan. Racecadotril is chemically known as N-[2-[(acetylthio) methyl] -l-oxo-3-phenylpropyl] glycine phenyl methyl ester, (herein after referred by its generic name racecadotril) and represented by the formula (I).
  • HOBT hydroxyl benzotriazole
  • DCC dicyclohexyl amine carbodiimide
  • the process of present invention is simple, cost effective, eco-friendly, reproducible, robust and is well suited on commercial scale.
  • the present invention relates to a process for the preparation of N-[2-[(acetylthio) methyl]- l-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof.
  • the present invention relates to a process for the preparation of intermediate compound 2-(benzyl acrylolyl amino) acetic acid benzyl ester.
  • the present invention relates to a process for the preparation of 2-(benzyl acrylolyl amino) acetic acid benzyl ester of formula (la)
  • R is C1-C6 alkyl branched or straight chain or aryl.
  • HX is acid addition salts, such as those made with hydrochloric, hydrobromic, hydroiodic, methylsulfonic, perchloric, sulfuric, nitric, phosphoric, acetic, propionic, glycolic lactic pyruvic, malonic, succinic, maleic, fumaric, maleic, tartaric, citric, benzoic, carbonic cinnamic, mandelic, methanesulfonic, ethanesulfonic, benezenesulfonic,
  • Fig. 1 is a schematic representation of an embodiment of the process of present invention.
  • the present invention is directed to a process for the preparation of N-[2-[(acetylthio) methyl] -l-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof.
  • the present invention relates to a process for the preparation of intermediate compound 2-(benzyl acrylolyl amino) acetic acid benzyl ester.
  • R is C1-C6 alkyl branched or straight chain or aryl.
  • HX is acid addition salts, such as those made with hydrochloric, hydrobromic, hydroiodic, methylsulfonic, perchloric, sulfuric, nitric, phosphoric, acetic, propionic, glycolic, lactic pyruvic, malonic, succinic, maleic, fumaric, maleic, tartaric, citric, benzoic, carbonic cinnamic, mandelic, methanesulfonic, ethanesulfonic, benezenesulfonic,
  • the suitable base that can be used in step a) include inorganic or organic base.
  • Inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, ammonia and the like; and the organic bases such as triethylamine, tripropylamine, pyridine, dimethyl amino pyridine, diisopropylamine, diisopropylethylamine and the like, or mixture thereof, preferably triethylamine.
  • the organic solvents that can be used in step a) is selected from the group consisting of halogenated solvents such as dichloromethane, ethylene dichloride , chloroform, chlorobenzene, and the like; hydrocarbon solvents such as toluene, xylene, cyclohexane, n- hexane and the like; esters such as ethyl acetate, isopropyl acetate and the like: or mixtures thereof in various proportions without limitation.
  • halogenated solvents such as dichloromethane, ethylene dichloride , chloroform, chlorobenzene, and the like
  • hydrocarbon solvents such as toluene, xylene, cyclohexane, n- hexane and the like
  • esters such as ethyl acetate, isopropyl acetate and the like: or mixtures thereof in various proportions without limitation.
  • dichloromethane is being used.
  • the reaction temperature and time should be suitable to bring the reaction to completion at a minimum time, without the production of unwanted side products.
  • the reaction temperature is from about -20°C to about 40°C. Preferably at about -5°C to about 10 °C.
  • the time required for the reaction may also vary widely, depending on many factors, notably the reaction temperature and the nature of the reagent and solvent(s) employed. The time period is from about 1 hour to about 10 hours, preferably from about 1 hour to 5 hours.
  • the molar equivalent of base used can be from about 0.5 mole to about 10 moles on weight of the compound of formula V taken. Preferably, 1 mole is being used.
  • the molar equivalent of formula IV used can be from about 0.5 mole to about 5 moles on weight of the compound of formula V taken. Preferably, 1 mole is being used.
  • step b) the compound of formula II is being used in acid addition salt form that can be organic or inorganic acid salt namely hydrobromic acid salt, iodic acid salt, hydrogen sulfate salt, besylate salt, paratoluene sulfonate salt, mesylate salt, tartarate salt and the like.
  • acid addition salt form can be organic or inorganic acid salt namely hydrobromic acid salt, iodic acid salt, hydrogen sulfate salt, besylate salt, paratoluene sulfonate salt, mesylate salt, tartarate salt and the like.
  • paratoluene sulfonate is being prepared.
  • the R groups in the compounds of formula III and IV can be Ci-C 6 alkyl straight chain or branched or aryl namely methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, isopropyl, isobutyl, allyl, cyclohexyl, benzyl, phenyl, para nitro phenyl etc. preferably the R- group is ethyl.
  • the preferable compounds suitable for the preparation of compounds of formula III and IV include but are limited to ethyl chloro formate, benzyl chloro formate, isobutyl chloro formate, allyl chloro formate, phenyl chloro formate, paranitro phenyl chloro formate or mixtures thereof.
  • ethyl chloro formate Preferably ethyl chloro formate.
  • the reaction temperature is from about -20°C to about 40°C. preferably at about -5°C to about 10 °C.
  • the time required for the reaction may also vary widely, depending on many factors, notably the reaction temperature and the nature of the reagent and solvent(s) employed. The time period is from about 1 hour to about 10 hours, preferably from about 1 hour to 5 hours.
  • the intermediate compound of formula III is optionally isolated as and when needed.
  • reaction mixture can be carried out by common operation, but in consideration of the physical properties of the desired compound, crystallization, extraction, washing, column chromatography, etc. may be combined.
  • the processes of present invention can be carried out by one pot synthesis.
  • the intermediate compounds can be optionally purified by recrystallisation, using a solvent or mixture of solvents; or by converting into their corresponding acid addition salt and then processed back to the respective free base or free acid compounds.
  • the process of present invention provides the intermediates with higher yields and purities thus leading to higher yields and purities of final product.
  • a process according to the present invention by using the intermediates prepared by the processes of present invention preferably yields racecadotril (I) substantially pure form.
  • the racecadotril obtained by the process of present invention has purity at least about 98 area % by HPLC , preferably at least about 99 area%. More preferably at least about 99.5 area % by HPLC.
  • the intermediate compound of formula (la) obtained by the above described process of present invention can be further converted into Racecadotril of formula I by processes described in the art. Illustratively, by the process described in U.S. Patent No. US 6,835,851 B2.
  • the present invention provides a simple, ecofriendly, inexpensive, reproducible, robust processes for preparation intermediates of racecadotril, which forthwith are viably adaptable on a commercial scale.
  • reaction mass was brought to about 25 °C and stirred for 30min. he reaction mass was washed with 250ml. of water followed by 250ml. of 4% sodium bicarbonate solution and again with 250ml. of water. The organic layer was separated and washed with 4 gms of carbon. The resulted reaction solution was distilled ordinarily and then finally under vacuum. Then charged 75ml. of isopropyl alcohol and distilled under vacuum upto 80°C to obtain 2-(benzylacryloyl amino)acetic acid benzyl ester as the residue.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Emergency Medicine (AREA)
  • Medicinal Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Epidemiology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

The present invention relates to a process for the preparation of N-[2-[(acetylthio) methyl]-1-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof. More particularly the present invention relates to a process for the preparation of intermediate compound 2-(benzyl acrylolyl amino) acetic acid benzyl ester.

Description

A PROCESS FOR THE PREPARATION OF N-[2-[(ACETYLTHIO) METHYL]-1- OXO-3-PHENYLPROPYL] GLYCINE PHENYL METHYL ESTER AND
INTERMEDIATES THEREOF BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to a process for the preparation of N-[2-[(acetylthio) methyl]- l-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof.
More particularly the present invention relates to a process for the preparation of intermediate compound 2-(benzyl acrylolyl amino) acetic acid benzyl ester.
2. Description of the Related Art
Racecadotril is a neutral endopeptidase inhibitor used as antidiarrheal in the treatment of chronic cardiac insufficiency and is available under the brand names Hidrasec and Tiorfan. Racecadotril is chemically known as N-[2-[(acetylthio) methyl] -l-oxo-3-phenylpropyl] glycine phenyl methyl ester, (herein after referred by its generic name racecadotril) and represented by the formula (I).
Figure imgf000002_0001
U.S. Patent No. US 4,513,009 describes amino acid derivatives including racecadotril, a pharmaceutical composition and a method of treatment.
The US'009 patent also discloses a process for the preparation of racecadotril which is
Figure imgf000003_0001
U.S. Patent No. US 6,835,851 B2 discloses a process for the preparation of racecadotril which is illustrated by scheme below:
Figure imgf000004_0001
The processes described above involves expensive reagents such as hydroxyl benzotriazole (HOBT) and dicyclohexyl amine carbodiimide (DCC) and hazardous reagent like thionyl chloride thus rendering the processes expensive and not applicable on industrial scale.
Hence there is a need in the art for an improved process for the preparation of racecadotril and its intermediates, which avoids the use of hazardous and expensive reagents, while enhancing the desired product racecadotril with high yield and purity.
The process of present invention is simple, cost effective, eco-friendly, reproducible, robust and is well suited on commercial scale.
SUMMARY OF THE INVENTION
The present invention relates to a process for the preparation of N-[2-[(acetylthio) methyl]- l-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof.
More particularly the present invention relates to a process for the preparation of intermediate compound 2-(benzyl acrylolyl amino) acetic acid benzyl ester.
In an aspect, the present invention relates to a process for the preparation of 2-(benzyl acrylolyl amino) acetic acid benzyl ester of formula (la)
Figure imgf000005_0001
(la)
comprising :
a) reacting the compound 2-benzyl acrylic acid of formula V
COT
V
with the compound alkyl chloro formate of formula IV
Figure imgf000005_0002
Where R is C1-C6 alkyl branched or straight chain or aryl.
in the presence of suitable base and an organic solvent to give the compound 2-benzylacrylic (alkyl carbonic) anhydride of formula III which is optionally isolated
Figure imgf000005_0003
III
Where R is same as defined above,
b) reacting the compound of formula III with the compound glycine benzyl ester
thereof of formula II
Figure imgf000005_0004
II
Wherein HX is acid addition salts, such as those made with hydrochloric, hydrobromic, hydroiodic, methylsulfonic, perchloric, sulfuric, nitric, phosphoric, acetic, propionic, glycolic lactic pyruvic, malonic, succinic, maleic, fumaric, maleic, tartaric, citric, benzoic, carbonic cinnamic, mandelic, methanesulfonic, ethanesulfonic, benezenesulfonic,
hydroxyethanesulfonic, p-toluene sulfonic, cyclohexanesulfamic, salicyclic, p- aminosalicylic, 2-phenoxybenzoic, and 2-acetoxy benzoic acid
to give the compound of formula (la).
BRIEF DESCRIPTION OF THE DRAWING
Fig. 1 : is a schematic representation of an embodiment of the process of present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is directed to a process for the preparation of N-[2-[(acetylthio) methyl] -l-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof.
More particularly the present invention relates to a process for the preparation of intermediate compound 2-(benzyl acrylolyl amino) acetic acid benzyl ester.
In an embodiment of the present invention, there is provided a process for the preparation of 2-(benzyl acrylolyl amino) acetic acid benzyl ester of formula (la)
Figure imgf000006_0001
(la)
comprising :
a) reacting the compound 2-benzyl acrylic acid of formula V
Figure imgf000006_0002
V
with the compound alkyl chloro formate of formula IV
Figure imgf000006_0003
IV
Where R is C1-C6 alkyl branched or straight chain or aryl.
in the presence of suitable base and an organic solvent to give the compound 2-benzylacrylic (alkyl carbonic) anhydride of formula III which is optionally isolated
Figure imgf000007_0001
III
Where R is same as defined above.
b) reacting the compound of formula III with the compound glycine benzyl ester
thereof of formula II
Figure imgf000007_0002
II
Wherein HX is is acid addition salts, such as those made with hydrochloric, hydrobromic, hydroiodic, methylsulfonic, perchloric, sulfuric, nitric, phosphoric, acetic, propionic, glycolic, lactic pyruvic, malonic, succinic, maleic, fumaric, maleic, tartaric, citric, benzoic, carbonic cinnamic, mandelic, methanesulfonic, ethanesulfonic, benezenesulfonic,
hydroxyethanesulfonic, p-toluene sulfonic, cyclohexanesulfamic, salicyclic, p- aminosalicylic, 2-phenoxybenzoic, and 2-acetoxy benzoic acid
to give the compound of formula (la).
The suitable base that can be used in step a) include inorganic or organic base.
Inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, ammonia and the like; and the organic bases such as triethylamine, tripropylamine, pyridine, dimethyl amino pyridine, diisopropylamine, diisopropylethylamine and the like, or mixture thereof, preferably triethylamine.
The organic solvents that can be used in step a) is selected from the group consisting of halogenated solvents such as dichloromethane, ethylene dichloride , chloroform, chlorobenzene, and the like; hydrocarbon solvents such as toluene, xylene, cyclohexane, n- hexane and the like; esters such as ethyl acetate, isopropyl acetate and the like: or mixtures thereof in various proportions without limitation. Preferably, dichloromethane is being used.
The reaction temperature and time should be suitable to bring the reaction to completion at a minimum time, without the production of unwanted side products. The reaction temperature is from about -20°C to about 40°C. Preferably at about -5°C to about 10 °C. The time required for the reaction may also vary widely, depending on many factors, notably the reaction temperature and the nature of the reagent and solvent(s) employed. The time period is from about 1 hour to about 10 hours, preferably from about 1 hour to 5 hours.
The molar equivalent of base used can be from about 0.5 mole to about 10 moles on weight of the compound of formula V taken. Preferably, 1 mole is being used.
The molar equivalent of formula IV used can be from about 0.5 mole to about 5 moles on weight of the compound of formula V taken. Preferably, 1 mole is being used.
In step b) the compound of formula II is being used in acid addition salt form that can be organic or inorganic acid salt namely hydrobromic acid salt, iodic acid salt, hydrogen sulfate salt, besylate salt, paratoluene sulfonate salt, mesylate salt, tartarate salt and the like. Preferably paratoluene sulfonate is being prepared.
The R groups in the compounds of formula III and IV can be Ci-C6 alkyl straight chain or branched or aryl namely methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, isopropyl, isobutyl, allyl, cyclohexyl, benzyl, phenyl, para nitro phenyl etc. preferably the R- group is ethyl.
The preferable compounds suitable for the preparation of compounds of formula III and IV include but are limited to ethyl chloro formate, benzyl chloro formate, isobutyl chloro formate, allyl chloro formate, phenyl chloro formate, paranitro phenyl chloro formate or mixtures thereof. Preferably ethyl chloro formate.
The reaction temperature is from about -20°C to about 40°C. preferably at about -5°C to about 10 °C. The time required for the reaction may also vary widely, depending on many factors, notably the reaction temperature and the nature of the reagent and solvent(s) employed. The time period is from about 1 hour to about 10 hours, preferably from about 1 hour to 5 hours.
The intermediate compound of formula III is optionally isolated as and when needed.
After completion of the reaction, isolation of the desired compound from the
reaction mixture can be carried out by common operation, but in consideration of the physical properties of the desired compound, crystallization, extraction, washing, column chromatography, etc. may be combined.
Optionally the processes of present invention can be carried out by one pot synthesis. The intermediate compounds can be optionally purified by recrystallisation, using a solvent or mixture of solvents; or by converting into their corresponding acid addition salt and then processed back to the respective free base or free acid compounds.
Advantageously, the process of present invention provides the intermediates with higher yields and purities thus leading to higher yields and purities of final product.
A process according to the present invention by using the intermediates prepared by the processes of present invention preferably yields racecadotril (I) substantially pure form. Thus the racecadotril obtained by the process of present invention has purity at least about 98 area % by HPLC , preferably at least about 99 area%. More preferably at least about 99.5 area % by HPLC.
The intermediate compound of formula (la) obtained by the above described process of present invention can be further converted into Racecadotril of formula I by processes described in the art. Illustratively, by the process described in U.S. Patent No. US 6,835,851 B2.
The present invention provides a simple, ecofriendly, inexpensive, reproducible, robust processes for preparation intermediates of racecadotril, which forthwith are viably adaptable on a commercial scale.
Having described the invention with reference to certain preferred embodiments, other embodiments will become apparent to one skilled in the art from consideration of the specification. The invention is further defined by reference to the following examples describing in detail the preparation of the composition and methods of use of the invention.
It will be apparent to those skilled in the art that many modifications, both to materials and methods, may be practiced without departing from the scope of the invention.
EXAMPLES
Example -1 : Preparation of 2-(benzyl acrylolyl amino) acetic acid benzyl ester (la) using ethyl chloro formate
50gms of 2-benzyl acrylic acid, 500ml. of dichloromethane and 34.3 gms of triethylamine were charged in a clean and dry 1 lit. 4 neck R.B. flask. The reaction mass was cooled to about -5° C and 36.84 gms of ethylchloroformate was added drop-wise at about -5° C and stirred for about 30min. at the same temperature . After completion of the reaction, 104.03gr. of glycine benzyl ester p-tosylate, 34.3gr. of triethylamine and 200ml. of dichloromethane were added at -5° C and stirred for 1 hr 30min. at the same temperature. After completion of reaction, the reaction mass was brought to about 25 °C and stirred for 30min. he reaction mass was washed with 250ml. of water followed by 250ml. of 4% sodium bicarbonate solution and again with 250ml. of water. The organic layer was separated and washed with 4 gms of carbon. The resulted reaction solution was distilled ordinarily and then finally under vacuum. Then charged 75ml. of isopropyl alcohol and distilled under vacuum upto 80°C to obtain 2-(benzylacryloyl amino)acetic acid benzyl ester as the residue.
Wt: 104gr.
To the 104gr. of residue, added 104ml. of isopropyl alcohol and 104ml. of n-hexane at ambient temperature. The resulted solution was cooled to 0-5°C and stirred for 30min. at the same temperature. The resulted solution was filtered and washed with 50ml. of n-hexane to obtain the 2-(benzylacryloyl amino)acetic acid benzyl ester as a pure solid.
Yield: 50-53gr. Purity by HPLC: 99.8%.
Example-2: Preparation of 2-(benzyl acrylolyl amino) acetic acid benzyl ester (la) using benzyl chloro formate
The process is performed in the similar manner as described in the above Ex 1 by replacing ethyl chloro formate with benzyl chloro formate.
Yield: lOgms. (% Yield: 42%); Purity by HPLC: 98.3%.
Example-3: Preparation of 2-(benzyl acrylolyl amino) acetic acid benzyl ester (la) using isobutyl chloro formate
The process is performed in the similar manner as described in the above Ex 1 by replacing ethyl chloro formate with isobutyl chloro formate .
Yield: 9.8gms. (%Yield: 41%); Purity by HPLC: 99.1%.
Example-4: Preparation of 2-(benz I acrylolyl amino) acetic acid benzyl ester (la) using allyl chloro formate
The process is performed in the similar manner as described in the above Ex 1 by replacing ethyl chloro formate with allyl chloro formate.
Yield: 1 lgms. (% Yield: 46%); Purity by HPLC: 98.5%.
Example-5: Preparation of 2-(benzyI acrylolyl amino) acetic acid benzyl ester (la) using phenyl chloro formate
The process is performed in the similar manner as described in the above Ex 1 by replacing ethyl chloroformate with phenyl chloro formate.
Yield: 20.5gms (% Yield: 43%); Purity by HPLC: 98.7%. Example-6: Preparation of 2-(benzyl acrylolyl amino) acetic acid benzyl ester (la) using p-nitro phenyl chloroformate
The process is performed in the similar manner as described in the above Ex 1 by replacing ethyl chloro formate with p-nitro phenyl chloro formate.
Yield : 10.5 gms (% Yield: 44%); Purity by HPLC: 99.3%

Claims

We Claim:
1) A process for the preparation of 2-(ben2yl acrylolyl amino) acetic acid benzyl ester of formula (la)
Figure imgf000012_0001
(la)
comprising :
a) reacting the compound 2-benzyl acrylic acid of formula V
Figure imgf000012_0002
with the compound alkyl chloro formate of formula IV
Figure imgf000012_0003
Where R is Ci-Ce alkyl branched or straig t chain or aryl.
in the presence of suitable base and an organic solvent to give the compound 2- benzylacrylic (alkyl carbonic) anhydride of formula III which is optionally isolated
Figure imgf000012_0004
III
Where R is same as defined above,
b) reacting the compound of formula III with the compound glycine benzyl ester or a salt thereof of formula II
Figure imgf000013_0001
II
Wherein HX is is acid addition salts, such as those made with hydrochloric, hydrobromic, hydroiodic, methylsulfonic, perchloric, sulfuric, nitric, phosphoric, acetic, propionic, glycolic, lactic pyruvic, malonic, succinic, maleic, fumaric, maleic, tartaric, citric, benzoic, carbonic cinnamic, mandelic, methanesulfonic, ethanesulfonic, benezenesulfonic, hydroxyethanesulfonic, p-toluene sulfonic, cyclohexanesulfamic, salicyclic, p- aminosalicylic, 2-phenoxybenzoic, and 2-acetoxy benzoic acid
to give the compound of formula (la).
2) The process of claim 1, wherein the suitable base that can be used in step a) is selected from the group consisting of inorganic bases like as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, ammonia, organic bases like triethylamine, tripropylamine, pyridine, dimethyl amino pyridine,
diisopropylamine, diisopropylethylamine or mixture thereof, preferably triethylamine.
3) The process of claim 1 , wherein the organic solvents that can be used in step a) is selected from the group consisting of halogenated solvents like dichloromethane, ethylene dichloride chloroform, chlorobenzene, hydrocarbon solvents like toluene, xylene, cyclohexane, n- hexane and the like; esters such as ethyl acetate, isopropyl acetate and the like: or mixtures thereof in various proportions without limitation. Preferably, dichloromethane is being used. 4) The process of claim 1, wherein the molar equivalent of base used is from about 0.25
mole to about 10 moles on weight of the compound of formula V taken, preferably, 1 mole is being used.
5) The process of claim 1, wherein the molar equivalent of formula IV used is from about
0.25 mole to about 5 moles on weight of the compound of formula V taken, preferably, 1 mole is being used.
6) A process of claim 1, wherein organic solvent is selected form the group consisting of alcohols like methanol, ethanol, propanol, isopropanol, butanol, esters like ethyl
acetate, methyl acetate, n-butyl acetate, chlorinated solvents like methylene dichloride.
ethylene dichloride, chloroform; aprotic polar solvents dimethyl formamide, dimethyl acetamide and dimethyl sulfoxide, preferably dimethyl sulfoxide.
7) A process of claim 1, wherein reaction steps are carried out at temperatures from about - 20°C to about 40°C, preferably from about -5°C to about 10°C.
8) Racecadotril (I) of preceding claims has a purity of at least about 98 area % by HPLC.
9) Racecadotril (I) of claim 8, has a purity of at least about 99 area % by HPLC.
10) Racecadotril (I ) of preceding claims has less than about 0.1 area % of individual impurity and 0.5 area % of total impurities by HPLC .
PCT/IN2011/000132 2011-03-02 2011-03-02 A process for the preparation of n-[2-[(acetylthio) methyl]-1-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof Ceased WO2012117410A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/IN2011/000132 WO2012117410A1 (en) 2011-03-02 2011-03-02 A process for the preparation of n-[2-[(acetylthio) methyl]-1-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/IN2011/000132 WO2012117410A1 (en) 2011-03-02 2011-03-02 A process for the preparation of n-[2-[(acetylthio) methyl]-1-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof

Publications (1)

Publication Number Publication Date
WO2012117410A1 true WO2012117410A1 (en) 2012-09-07

Family

ID=46757408

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IN2011/000132 Ceased WO2012117410A1 (en) 2011-03-02 2011-03-02 A process for the preparation of n-[2-[(acetylthio) methyl]-1-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof

Country Status (1)

Country Link
WO (1) WO2012117410A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107129450A (en) * 2017-06-05 2017-09-05 山东裕欣药业有限公司 A kind of racecadotril crystalline compounds and preparation method thereof
CN107486096A (en) * 2016-06-12 2017-12-19 景津环保股份有限公司 A kind of instant mixed stirring device of drum type brake medicinal powder
CN110272363A (en) * 2019-06-11 2019-09-24 扬子江药业集团江苏海慈生物药业有限公司 A kind of synthetic method of racecadotril

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2736728A (en) * 1954-12-06 1956-02-28 Lilly Co Eli Preparation of lysergic acid amides
US20020055645A1 (en) * 2000-11-09 2002-05-09 Thierry Monteil Process for synthesizing N-(mercaptoacyl) amino acid derivatives from alpha-substituted acrylic acids
US20020077481A1 (en) * 1996-12-11 2002-06-20 Martin Karpf Process for the preparation of mixed anhydrides
US6610880B1 (en) * 1999-10-13 2003-08-26 Akzo Nobel Nv Process for preparing peroxides using mixed anhydrides

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2736728A (en) * 1954-12-06 1956-02-28 Lilly Co Eli Preparation of lysergic acid amides
US20020077481A1 (en) * 1996-12-11 2002-06-20 Martin Karpf Process for the preparation of mixed anhydrides
US6610880B1 (en) * 1999-10-13 2003-08-26 Akzo Nobel Nv Process for preparing peroxides using mixed anhydrides
US20020055645A1 (en) * 2000-11-09 2002-05-09 Thierry Monteil Process for synthesizing N-(mercaptoacyl) amino acid derivatives from alpha-substituted acrylic acids

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107486096A (en) * 2016-06-12 2017-12-19 景津环保股份有限公司 A kind of instant mixed stirring device of drum type brake medicinal powder
CN107486096B (en) * 2016-06-12 2023-05-02 景津装备股份有限公司 Instant mixing stirring device of drum formula powder
CN107129450A (en) * 2017-06-05 2017-09-05 山东裕欣药业有限公司 A kind of racecadotril crystalline compounds and preparation method thereof
CN107129450B (en) * 2017-06-05 2019-05-03 山东裕欣药业有限公司 A kind of racecadotril crystalline compounds and preparation method thereof
CN110272363A (en) * 2019-06-11 2019-09-24 扬子江药业集团江苏海慈生物药业有限公司 A kind of synthetic method of racecadotril

Similar Documents

Publication Publication Date Title
US20130041180A1 (en) Process for preparing (r)-2-acetamido-n-benzyl-3-methoxy-propionamide
CA2476022C (en) A process for preparing a phenylalanine derivative and intermediates thereof
US20170226047A1 (en) Process for the purification of melphalan
CN107810189B (en) Method for preparing nitrogen mustard derivatives
WO2016024284A2 (en) A process for the preparation of mirabegron and its intermediates
EP2970102B1 (en) An improved process for the synthesis of melphalan and the hydrochloride salt
WO2012117410A1 (en) A process for the preparation of n-[2-[(acetylthio) methyl]-1-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof
US20110039937A1 (en) Novel process for the preparation of vorinostat
TWI634100B (en) Process for the preparation of lacosamide
WO2007112613A1 (en) Preparation of n-substituted isothiazolinone derivatives
US9790170B2 (en) Method for preparing lacosamide
IT201800006337A1 (en) LIFITEGRAST PREPARATION PROCEDURE
US20240262805A1 (en) Method for producing compound or pharmaceutically acceptable salt thereof
RU2512591C2 (en) Method of producing pleuromutilins
US12077484B2 (en) Process for the synthesis of melphalan
JP5704763B2 (en) Production of trans-4-aminocyclopent-2-ene-1-carboxylic acid derivative
WO2013098826A1 (en) "a process for the preparation of n-[2-[(acetylthio) methyl]-1-oxo-3-phenylpropyl] glycine phenyl methyl ester and intermediates thereof"
JP5709101B2 (en) Method for producing hydroxyproline derivative
EP3260442B1 (en) Process for preparation of optically pure n-substituted-3-methoxypropionic acid derivatives
US20160214927A1 (en) Process for the preparation of nepafenac
CA3108358C (en) Preparation method for (1r,3s)-3-amino-1-cyclopentanol and salts thereof
JP2024117554A (en) New dehydration condensation agent
CN111247127B (en) Method for producing intermediate compounds used in the synthesis of drugs
US20110144346A1 (en) Method for producing n-phenyl-n-(4-piperidinyl) amide salts
US20180237377A1 (en) Process for the Synthesis of Melphalan and the Hydrochloride Salt

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 1327/CHENP/2012

Country of ref document: IN

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11859828

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11859828

Country of ref document: EP

Kind code of ref document: A1