title: In vitro antibacterial activity of three new quinolone derivatives: rosoxacin, norfloxacin, pefloxacin.
abstract: The in vitro activities of rosoxacin, norfloxacin and pefloxacin against 480 bacterial strains were studied. MIC90s of norfloxacin and pefloxacin were less than or equal to 2 micrograms/ml for E. coli, Klebsiella sp., E. cloacae, Proteus sp. and Staphylococcus sp., less than or equal to 8 micrograms/ml for C. freundii, Providencia sp., S. faecalis, and non fermentative Gram-negative bacteria, while they were of 32 micrograms/ml for S. marcescens. Rosoxacin exhibited a lower activity with MIC90s 2 to 16 fold higher against Enterobacteriaceae and P. aeruginosa. Ninety per cent of isolates resistant to nalidixic-acid appeared susceptible to norfloxacin and pefloxacin with MIC less than or equal to 16 micrograms/ml.
mesh_terms: D042462:4-Quinolones; D000890:Anti-Infective Agents; D004352:Drug Resistance, Microbial; D004755:Enterobacteriaceae / Q000187:drug effects; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D009268:Nalidixic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D009643:Norfloxacin; D015366:Pefloxacin; D011804:Quinolines / Q000494:pharmacology*; D015363:Quinolones; D013045:Species Specificity
chemical_list: D042462:4-Quinolones; D000890:Anti-Infective Agents; D011804:Quinolines; D015363:Quinolones; D015366:Pefloxacin; D009268:Nalidixic Acid; C021083:rosoxacin; D009643:Norfloxacin