[EN] PROCESS FOR PREPARING PURE CEPHALOSPORINE INTERMEDIATES<br/>[FR] PROCEDE DE PREPARATION D'INTERMEDIAIRES DE CEPHALOSPORINE PURES
申请人:HETERO DRUGS LTD
公开号:WO2006008749A1
公开(公告)日:2006-01-26
The present invention relates to a process for preparing key intermediates for cephalosporin antibiotics substantially free of undesired delta A2 isomer. Thus, 7-aminocephalosporanic acid (7-ACA) is silylated with hexamethyldisilazane in cyclohexane at reflux temperature. (6R,7R)-3-[(Acetyloxy)methyl]-7-(trimethylsilyl)aminoceph-3-em-4-oic acid obtained is reacted with the mixture of N-methylpyrrolidine and trimethylsilyliodide in cyclohexane, desilylated with isopropyl alcohol and treated with hydrochloric acid to obtain [6R-(6a,7b)]-1-[[7-Amino-2-carboxy-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-3-yl]methyl]-1-methylpyrrolidinium inner salt hydrochloride. [6R-(6a,7b)]-1-[[7-Amino-2-carboxy-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-3-yl]methyl]-1-methylpyrrolidinium inner salt hydrochloride is N-acylated with syn-2-(2-aminothiazol-4-yl)-2-methoxyimino acetic acid 2-benzothiazolyl thioester (MAEM) followed by treatment with hydrochloric acid to give cefepime dihydrochloride monohydrate.
[EN] A NEW PROCESS FOR THE PREPARATION OF CEFDITOREN USING THE THIOESTER OF THIAZOLYLACETIC ACID<br/>[FR] NOUVELLE METHODE DE PREPARATION DE CEFDITORENE UTILISANT LE THIOESTER D'ACIDE THIAZOLYLACETIQUE
申请人:ORCHID CHEMICALS & PHARM LTD
公开号:WO2003099826A1
公开(公告)日:2003-12-04
The present invention provides a process for the preparation of Cefditoren of formula (I) which comprises acylating 7-amino-cephem carboxylic acids of the general formula (IV), where R3 is hydrogen or trimethylsilyl with thioester derivatives of the formula (II), where R1 represents C1 - C4 alkyl or phenyl in an organic solvent in the presence of an organic base at a temperature in the range of -10 °C to 30 °C.
Process for the preparation of cefditoren using the thioester of thiazolylacetic acid
申请人:——
公开号:US20030225265A1
公开(公告)日:2003-12-04
The present invention provides a process for the preparation of Cefditoren of formula (I)
1
which comprises acylating 7-amino-cephem carboxylic acids of the general formula (IV), where R
3
is hydrogen or trimethylsilyl with thioester derivatives of the formula (II), where R
1
represents C
1
-C
4
alkyl or phenyl in an organic solvent in the presence of an organic base at a temperature in the range of −10 ° C. to 30 ° C.
[EN] PROCESS FOR THE PREPARATION OF CEPHALOSPORIN ANTIBIOTICS<br/>[FR] PROCEDE DE PREPARATION D'ANTIBIOTIQUES CEPHALOSPORINES
申请人:ORCHID CHEMICALS & PHARM LTD
公开号:WO2004037833A1
公开(公告)日:2004-05-06
The present invention more particularly relates to a process for the preparation of cephalosporin antibiotics of the formula (I) wherein R1 represents hydrogen, trityl, CH3, CRaRbCOORYc where Ra and Rb independently represent hydrogen or methyl and Rc represents hydrogen or (C1-C6)alkyl; R2 is carboxylate ion or COORd, where Rd represents hydrogen, ester or a counter ion which forms a salt; R3 represents hydrogen, CH3, CH2OCOCH3, CH=CH2.
Process for the preparation of cephalosporin antibiotic
申请人:Deshpande Balwant Pandurang
公开号:US20050080070A1
公开(公告)日:2005-04-14
A process for the preparation of cephalosporin antibiotic of the formula (I)
which comprises:
(i) activating the compound of formula (III) as acid halide in an organic solvent
(ii) treating the reaction mass obtained from step (i) with water (iii) separating the organic layer containing the reactive derivative of formula (III) and condensing it with 7-amino cephalosporin derivative by maintaining the pH in the range 5.0-10.0 using an inorganic base of the formula (XV), and
iv) cyclizing the compound of formula (XVI)
with thiourea in the presence of solvent and salt of organic or inorganic acid at a temperature in the range of −50 to +50° C. to produce compound of formula (I).