NOVEL DELTA3-CEPHEM DERIVATIVE AND ITS PREPARATION

摘要

NEW MATERIAL:A compound of formula I (R<1>, R<2> are lower alkyl, nitro; A is 1-3C alkylene; R<3> is lower alkyl) and its salt. EXAMPLE:7-{alpha-( 2-Tritylamino-4-thiazolyl )-alpha-[2-( 2-methyl-5-nitro-1-imidazolyl )- ethoxyimi]acetamide}-3-[( 1-methyl-5-tetrazolyl )thiomethyl]-DELTA<3>-cephem-4-carboxylic diphenylmethyl ester. USE:A powerful antibacterial against gram-positive and -negative bacteria, in particular against Pseudomanas areugiosa and anaerobic bacteria. PREPARATION:The reaction between a substituted oxyiminothiazolylacetic acid derivative of formula III (R<4> is amino-protecting group) and a 7-amino-DELTA<3>-cephem derivative of formula IV (R<5> is H, carboxyl-protecting group) is followed by deptrotection. The compound of formula III as a starting substance is novel and obtained from (Z)-alpha-hydroxyimino-alpha-(2-tritylamino-4-thiazolyl)-acetic ethyl ester hydrochloride.