GB1319173A - 7-acylated-3-substituted cephalosporin compounds - Google Patents

Abstract

1319173 7 - Acylated - 3 - substituted cephalosporins FUJISAWA PHARMACEUTICAL CO Ltd 17 June 1971 28462/71 Heading C2A The invention comprises cephalosporins of the general Formula I wherein R is hydrogen, optionally substituted alkyl having 1 to 4 carbon atoms, optionally substituted aryl, thenyl or furyl radicals, R<SP>2</SP> is an acyl radical containing more than one carbon atom, R<SP>3</SP> is a hydrogen atom, an azido group or a heterocyclic-thio radical and M is a hydrogen atom or a pharmaceutically acceptable cation. A process for the preparation of compounds of Formula I comprises acylating a compound of Formula II with a disubstituted acetic acid of Formula III or with a reactive derivative thereof. A further process for the preparation of compounds of Formula I comprises reacting a compound of Formula IV with a nucleophile of formula R<SP>3 1</SP>-H wherein R<SP>3 1</SP> is azido or a heterocyolic-thio radical or with an alkali metal salt thereof. A third process for the preparation of compounds of Formula I comprises reacting a compound of Formula VI with a silylating agent, reacting the resulting silylated compound with a halogenating agent to give a halogenated compound which is reacted with an alkanol or alkali metal alkoxide. These reactions are followed by acylation with a disubstituted acetic acid of Formula III or with a reactive derivative thereof and hydrolysis of the acylated product. A fourth process for preparing the compounds of Formula I comprises reacting a compound of Formula VIII with a carboxylic acid of formula R<SP>2</SP>-OH or with a reactive derivative thereof. Pharmaceutical preparation containing compounds of Formula I may be prepared which are suitable for oral or parenteral administration.