Quantitative structure–Activity relationship studies on some nonbenzodiazepine series of compounds acting at the benzodiazepine receptor Original Research Article

Quantitative structure–activity relationship (QSAR) studies have been made on a few non-benzodiazepine series of compounds such as 3-substituted imidazo[1,2-b]pyridazines, 2-phenylimidazo[1,2-α]pyridines, 2-(alkoxycarbonyl)imidazo[2,1-b]benzothiazoles, and 2-arylquinolines. For the first series of compounds a Fujita–Ban approach has been followed, which revealed the highest activity contribution for 3,4-OCH2O group of 2-phenyl moiety and for a methoxy group at 6-position. For the rest of the series, a Hansch approach has been adopted. The hydrophobic and electronic properties of the various substituents have been found to play major roles in the binding of these compounds with the receptor. Based on these studies, a hypothetical model for the drug–receptor interaction has been proposed.