Synthesis, structure, and solvatochromic properties of pharmacologically active 5-substituted 5-phenylhydantoins

Abstract

A series of 5-substituted 5-phenylhydantoins was synthesized and their UV absorption spectra were recorded in the region 200-400 nm in selected solvents of different polarity. The effects of solvent dipolarity/polarizability and solvent-solute hydrogen-bonding interactions were analyzed by means of the linear solvation energy relationship concept proposed by Kamlet and Taft. The lipophilicities of the investigated hydantoins were estimated by calculation of their log P values. The quantitative relationship between the ratio of the contributions of specific solvent interactions and the corresponding lipophilicity parameter is discussed. The correlation equations were combined with the corresponding ED50 values and different physicochemical parameters to generate new equations that demonstrate the reasonable relationships between solute-solvent interactions and the structure-activity parameters. In order to determine a spectroscopic assignment of the absorption bands in different solvents, quantum chemical calculations were done.