Linear solvation energy relationships in the study of the solvatochromic properties and liquid chromatographic retention behaviour of benzodiazepines

The solvatochromic behaviour of a series of benzodiazepines was studied in order to characterize their molecular properties [polarity/polarizability and hydrogen bonding (HB) acidity and basicity]. Such experimental parameters, compared with those calculated according to Kamlet and co-workers, were employed in the study of the chromatographic retention behaviour by means of linear solvation energy relationships. Various high-performance liquid and thin-layer chromatographic systems were analysed for testing the confidence of this methodology in the study of different retentions in reversed-phase (RP) and normal-phase (NP) chromatographic systems. The most important parameters influencing benzodiazepine retention were established as size and HB basicity for RP retention and polarity and HB acidity or basicity for NP retention. For this series of solutes the present method also appears suitable for predicting retention in the studied systems and for selecting the optimum chromatographic ...