3-PYRAZOLO(1,5-A)PYRIDINIUM CEPHEM COMPOUNDS, THEIR PRODUCTION AND USE

摘要

A compound of the formula; Wherein R<0> stands for hydrogen atom, nitrogencontaining heterocyclic group, acyl group or aminoprotecting group, Z stands for S, S->O, O or CH2, R<4> stands for hydrogen atom methoxy group or formamido group, R<1><3> stands for hydrogen atom, methyl group, hydroxyl group or halogen atom and A stands for an optionally substituted pyrazol-2-yl group forming a fused ring at the 1,5-position or a physiologically or pharmaceutically acceptable salt or ester thereof. This compound is novel and has excellent antibacterial activity.