Chromatographic data for pharmacological classification of imidazol(in)e drugs

Abstract

A set of eighteen imidazol(in)e derivative drugs of various pharmacological activity were analysed under different high-performance liquid chromatographic (HPLC) conditions. Capacity factors were determined employing methanol-buffer eluents at seven volume ratios and at pH 10.9, 7.0 and 2.9. The use of an alkaline buffer was possible owing to the application of poly(butadiene)-coated alumina (PBCA) as the stationary phase. Two systems employing octadecylsilica (ODS) columns were applied, one operated at pH 7.0 and the other at pH 2.9. Capacity factors of the test solute drugs were determined in 21 chromatographic systems. All the data were subjected to chemometric analysis despite the fact that, except for the PBCA systems, only a limited range of linearity of the logarithm of capacity factor versus volume fraction of methanol in mobile phase was observed. The matrix of 21 x 18 capacity factors was statistically analysed by the principal component method. The first two principal components accounted for 80% of the variance in the capacity factors studied. The principal component object scores clearly separated the agents into groups in accordance with their pharmacological classification. It was concluded that diverse retention data can provide more information relevant to the bioactivity of solutes than just a one-dimensional hydrophobicity scale.