Lipophilicity of antibacterial fluoroquinolones

Article Details

Citation
Copy to clipboard

Takács-Novák K, Józan M, Szász H

Lipophilicity of antibacterial fluoroquinolones

International Journal of Pharmaceutics. 1992 Feb 1;79(1-3):89-96.

PubMed ID
Not Available
Abstract

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

DrugBank Data that Cites this Article

Drugs