title: Factors influencing the in vitro activity of two new aryl-fluoroquinolone antimicrobial agents, difloxacin (A-56619) and A-56620.
abstract: The in vitro activity of difloxacin (A-56619) and A-56620, two new aryl-difluoroquinolones, was decreased by magnesium at 9 mM and in assay at pH 5.5 or in urine. Resistance was seen with members of the family Enterobacteriaceae, Pseudomonas aeruginosa, and Staphylococcus aureus repeatedly exposed to subinhibitory concentrations of the compounds. The frequency of resistance was similar to that found for other new quinolones.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D002939:Ciprofloxacin / Q000031:analogs & derivatives*; D004352:Drug Resistance, Microbial; D024841:Fluoroquinolones; D008274:Magnesium / Q000494:pharmacology; D010879:Piperazines / Q000494:pharmacology*; D011804:Quinolines / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D010879:Piperazines; D011804:Quinolines; D002939:Ciprofloxacin; C047225:difloxacin; D008274:Magnesium; C047224:sarafloxacin