SYNTHESIS AND STRUCTURE-ACTIVITY-RELATIONSHIPS OF 1-BETA-METHYLCARBAPENEMS WITH QUATERNARY AMMONIUM SIDE-CHAINS

The synthesis and antibacterial activity of 1 beta-methylcarbapenems w ith quaternary ammonium groups at the C-2 position have been studied. Two types of new carbapenem derivatives have been synthesized. These 1 beta-methylcarbapenems, one type having a yl-2-(1-piperazinyl)carbony l]pyrrolidinio-4-ylthio group and the other type having a ylhomopipera zinio-1-ylcarbonyl)pyrrolidin-4-ylthio group, show potent and well bal anced antibacterial activity as well as high stability against dehydro peptidase-I. The in vivo potency of these two carbapenems was compared with that of meropenem. The structure-activity relationships leading to these carbapenems are also described.