Synthesis and antipseudomonal activity of fluoroquinolonyl-penicillin derivatives

A series of ampicillin and amoxicillin derivatives containing an N-1-substi tuted-(6-fluoro-1,4-dihydro-4-oxoqinolin-3-yl) carbonyl moiety at the a-ami no group were prepared and their antibacterial activities were evaluated. T hese derivatives displayed a broad spectrum of antibacterial activity again st Gram-(+) and Gram-(-) bacteria. In comparison with the original antibiot ics, some of the derivatives were more active against Pseudomonas aeruginos a strains. However, their antibacterial activities decrease when N-1 substi tution was replaced with alkyl substituents. Interestingly, several product s induced filamentation in three strains of P. aeruginosa. (C) Elsevier, Pa ris.