CEPHALOSPORIN DERIVATIVES, PROCESS FOR THEIR PREPARATION AND ANTIBACTERIAL AGENTS

摘要

A cephalosporin derivative having the formula: (I) wherein R1 is a substituted amino group, R2 is an aryl or heterocyclic group which may be substituted, R3 is a hydrogen atom, a negative charge or a residue of an ester which can form a pharmaceutically acceptable hydrolyzable in a living body and X is an alkylene group; or a pharmaceutically acceptable salt thereof, a process for its preparation and an antibacterial agent comprising thereof. The cephalosporin of this invention is useful in the pharmaceutical fields and, particularly, as antibacterial agents.