The synthesis and biological activity of a novel series of 2-aryl penems.

substituent, found in the carbapenem thienamycin, to the corresponding position in the penemnucleus has resulted in highly potent and broad spectrum antibiotics. Wenowwish to report the investigation of a new series of penemswhich bear a substituted phenyl group in the 2-position. It has been found that the level of potency of these compoundsdepends critically on the nature of the substituent on the phenyl ring.