Antibacterial activity of new beta-lactam compounds

beta-lactam compounds are evergreen molecoles, infact, since the discovery of Penicillin and with the emergence of drug-resitant bacteria, the design and the synthesis of new derivatives containing the 2-azetidinone ring motif have always drawn the researcher attention in order to discover new chemotherapeutic agents with improved stability and biological activity. Here we describe the synthesis of new N- functionalized azetidin-2-one derivatives and evaluation for their antimicrobial activity. The best result was found with the compound A93b which, similarly to penicillins and cephalosporins, showed excellent activity againstGram +ve bacteria such as Sthapilococcus aereus, Streptococcus pyogenes and Streptococcus pneumonia (the MIC 50% values are 4, 4 and 2 µg/ml respectively). In particular the MIC values against Sthapilococcus aereus are the same of Ceftazidime, a great compound of cephalosporin's class. Instead, the MIC values, for Gram -ve organisms (as Klebisella pneumonia and Pseudomonas aeruginosa) are very high and comparable to those found for the penicillins against the same microorganisms. Therefore, by the results obtained would seem that A93b mimics the behavior of penicillins.These studies provide interesting insights into the further design of new compounds