RETENTION OF SUBSTITUTED BENZALDEHYDES ON RP-HPLC. CORRELATION WITH PARTITION COEFFICIENTS AND MOLECULAR DESCRIPTORS

Abstract

The RP-HPLC capacity (k′) of a series of substituted benzaldehydes were determined on a C18 column with methanol/water as the mobile phase. A linear relationship was found between log k′ and the volume fraction of methanol (ϕ) for most tested compounds with the correlation coefficient above 0.96 (except of 2,5-dihydroxybenzaldehyde). High correlation was found between log k′w and S, which are intercept and slope of plot of log k′ vs. ϕ, respectively. The values of k′, k′w, and S were quantitatively correlated with water solubility (Sw) and octanol-water partition coefficients (log Kow). Additionally, log k′w and S were highly correlated with various molecular descriptors, and major molecular descriptors governing the retention of these studied compounds in RP-HPLC were determined.