Process for Purification of 3-Alkenylcephem Carboxylic Acid
摘要:
The present report describes a novel and efficient method for enrichment of 7-aniino-3-[(Z)-propen-1-yl]-3-cephem-4-carboxylic acid (1) in a mixture of (Z/E) 7-amino-3[(Z/E)-propen-1-yl]-3-cephem-4-carboxylic acid via formation of 7-beta-isopropylideneammonium salt in acidic conditions. This method provides high yield and 7-amino-3-[(Z)-propen-1-yl]-3-cephem-4-carboxylic acid (1) having a low E-isomer content from a mixture containing very high proportion of E-isomer. The usage of these isopropylidene ammonium salts provides a method for separation of mixtures of cephalosporins where geometric isomerism about a double bond exists.
Process for the preparation of 3-propenyl cephalosporin DMF solvate
申请人:ORCHID CHEMICALS & PHARMACEUTICALS LIMITED
公开号:US20040087786A1
公开(公告)日:2004-05-06
The present invention relates to an improved process for the preparation of 3-propenyl cephalosporin DMF solvate, more particularly, the present invention relates to an improved process for the preparation of cefprozil DMF solvate of the formula (I), which is useful for the preparation of cefprozil of the formula (XIV).
1
The present report describes a novel and efficient method for enrichment of 7-aniino-3-[(Z)-propen-1-yl]-3-cephem-4-carboxylic acid (1) in a mixture of (Z/E) 7-amino-3[(Z/E)-propen-1-yl]-3-cephem-4-carboxylic acid via formation of 7-beta-isopropylideneammonium salt in acidic conditions. This method provides high yield and 7-amino-3-[(Z)-propen-1-yl]-3-cephem-4-carboxylic acid (1) having a low E-isomer content from a mixture containing very high proportion of E-isomer. The usage of these isopropylidene ammonium salts provides a method for separation of mixtures of cephalosporins where geometric isomerism about a double bond exists.