Preparation and antibiotic activity of monobactam analogues of nocardicins

A series of diverse beta-lactam analogues of nocardicins with interesting a ntimicrobial properties were prepared. Coupling of glucosamine to these com pounds improved their water solubility. Aminoacid derivatives produced a st ereoinduction on the quaternary enantiotopic carbon of the starting compoun d 1. Evaluation of their antimicrobial activity showed that the introduction of alpha-aminoacids to monobactams increased their activity. The importance of asymmetric carbon is exemplified by the higher antibiotic activity of L-al pha-aminoacids than the D-series. No significant difference was observed between fluorinated and non-fluorina ted monobactams.