Lipophilicity of antibacterial fluoroquinolones

摘要: Abstract The octanol/water partition coefficients of nine antibacterial fluoroquinolones and nalidixic oxolinic acids were investigated. pH-partition profile amphoteric obtained between pH 4 10 showed maximum partitioning at the isoelectric point. From two microspecies (zwitterionic nonionic forms) which exist predominantly this pH, form is assumed to be transferred into octanol phase. A relationship derived apparent true coefficients, valid for ampholyte compounds capable forming zwitterions having present in significant amounts. On bases three groups examined are distinguished: lipophilic (e.g., pefloxacin amifloxacin), molecules intermediate lipophilicity (such as ciprofloxacin ofloxacin, etc.) hydrophilic derivatives norfloxacin lomefloxacin, etc.). influence structural modification on these drugs discussed.