FTIR investigation of solvent-induced carbonyl band shifts of 17β-hydroxy-17A-picolyl-androst-4-en-3-one

Abstract

Polar functional groups in the A- and D-ring (positions C-3 and C-17) are common for the most of natural and synthetic steroid hormones. It is assumed that these pharmacophoric groups are involved in the strong hydrogen bonding interactions with the respective steroid receptors. Infrared spectroscopy studies of 17β-hydroxy-17α-picolyl-an-drost-4-en-3-one were undertaken in 13 organic solvents to investigate solvent-solute interactions. The wavenumbers of carbonyl stretching vibration v(C=O) in different solvents were correlated with the solvent acceptor number (AN), the linear solvation energy relationships (LSER) and extended KBM-Buckingham equation. Significant correlation of the position of the carbonile band with empirical parameters was obtained in alcoholic and non-alcoholic solvents. Based on the obtained results it was concluded that the hydrogen bonding formation and the dipolarity/polarizability properties are important factors that determine position of carbonyl group band in the IR spectra, and are also important for the interactions in biological systems.