title: In vitro activity of Ro 23-6240, a new difluoroquinolone derivative, compared with that of other antimicrobial agents.
abstract: Ro 23-6240 is a new difluorinated quinolone antimicrobial agent. Its in vitro activity against a wide range of bacteria was compared with those of other quinolones and beta-lactams. Generally, members of the family Enterobacteriaceae were inhibited by low concentrations of Ro 23-6240 (MIC90 [MIC for 90% of isolates tested], less than or equal to 1 microgram/ml). Ninety percent of Staphylococcus aureus (including methicillin-resistant strains) and Neisseria gonorrhoeae isolates were inhibited by 0.5 microgram/ml. Pseudomonas aeruginosa (MIC90, 2 micrograms/ml) and Bacteroides fragilis (MIC90, 4 micrograms/ml) showed intermediate susceptibility, and Streptococcus pneumoniae (MIC90, 8 micrograms/ml) was less susceptible. Strains resistant to nalidixic acid were less susceptible to all the quinolones tested. The protein binding of Ro 23-6240 (5 micrograms/ml) was 27%.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects*; D001439:Bacteroides / Q000187:drug effects; D002939:Ciprofloxacin / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D004755:Enterobacteriaceae / Q000187:drug effects; D016576:Fleroxacin; D006801:Humans; D007769:Lactams; D008826:Microbial Sensitivity Tests; D009344:Neisseria gonorrhoeae / Q000187:drug effects; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D011804:Quinolines / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects; D013296:Streptococcus pneumoniae / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D007769:Lactams; D011804:Quinolines; D002939:Ciprofloxacin; D016576:Fleroxacin