Determination of Partition Coefficients of 2-Amino-2-Oxazolines by RP-HPLC: Application to Hydrophobicity Studies

Abstract

A comparative study of the hydrophobicity for a series of bioactive 5-aryloxy-methyl-2-amino-2-oxazolines is reported. Octanol-water partition coefficients were measured using the classical shake-flask method. For two lipophilic compounds, high-performance liquid chromatography (HPLC) was used as a detector for the shake-flask method. The capacity factors (log k') were determined by an HPLC method using methanol-water as a mobile phase and a C₁₈ column as stationary phase. The influence of the mobile phase composition was examined, allowing the determination of log k'_w values through extrapolation to 100% water from capacity factors data. The relationship between the pH eluent and the capacity factor was studied by working at different pH values.