| abstract |
A compound of the formula; ##STR1## wherein R 0 stands for hydrogen atom, nitrogen-containing heterocyclic group, acyl group or esterified carboxyl group, Z stands for S, S→O, O or CH 2 , R 4 stands for hydrogen atom, methoxy group or formamido group, R 13 stands for hydrogen atom, methyl group, hydroxyl group or halogen atom and A stands for an optionally substituted imidazol-1-yl group forming a condensed ring at the 2,3- or 3,4-position or a physiologically or pharmaceutically acceptable salt or ester thereof. n This compound is novel and has excellent antibacterial activity. |