NEW CEPHALOSPORIN COMPOUNDS AND THE PRODUCTION THEREOF

摘要

A class of new caphalosporin compounds (syn-isomer) is now provided, which is useful as antibacterial agent and is represented by the general formula (I) wherein R1 is an amino group or a protected amino group; R2 is a lower alkyl group, a carboxymethyl group or a protected carboxymethyl group; R3 is a hydrogen atom, a salt-forming cation or a carboxyl-protecting group; A is an unsubstituted or substituted phenyl group, an unsubstituted or substituted furyl group, an unsubstituted or substituted thiazolyl group or an unsubstituted or substituted 3-lower-alkylthiazolio group, and a pharmaceutically acceptable salt or ester thereof.