title: In vitro studies of S-25930 and S-25932, two new 4-quinolones.
abstract: The in vitro activity of S-25930 and S-25932 was compared with that of ciprofloxacin, norfloxacin and nalidixic acid against 740 clinical isolates. The data indicate that S-25930 was more active against Enterobacteriaceae than S-25932 and the latter was more active against gram-positive species. A study of clinical isolates resistant to chemically non-related classes of antibiotics revealed no cross-resistance. Nalidixic acid resistant Enterobacteriaceae showed an eight-fold decrease in susceptibility to the new agents. The killing kinetics of both compounds were good, S-25932 having an optimal bactericidal effect at a concentration of 0.5 mg/l. The data suggests that both agents are effective broad spectrum antibiotics.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D002939:Ciprofloxacin; D004352:Drug Resistance, Microbial; D004492:Edetic Acid / Q000494:pharmacology; D004755:Enterobacteriaceae / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects; D006801:Humans; D007700:Kinetics; D008826:Microbial Sensitivity Tests; D009268:Nalidixic Acid / Q000494:pharmacology; D009643:Norfloxacin / Q000494:pharmacology; D011804:Quinolines / Q000494:pharmacology; D011807:Quinolizines / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D011804:Quinolines; D011807:Quinolizines; D009268:Nalidixic Acid; C049886:ibafloxacin; D002939:Ciprofloxacin; C049887:S 25932; D004492:Edetic Acid; D009643:Norfloxacin