Atomic and molecular parameters-based comparative QSAR study on tetrahydroimidazodiazepinone derivatives

The Quantitative Structure Activity Relationship (QSAR) models of 21 tetrahydroimidazodiazepinone (TIBO) derivatives have been made with the help of atomic and molecular properties. The molecular modeling and geometry optimization have been carried out using CAChe software employing semiempirical methods. The values of atomic properties have been calculated by softness calculator, and molecular properties by PM3 method using MOPAC 2002. The study indicates that molecular properties predict the activity of tetrahydroimidazodiazepinone derivatives in a better way as indicated by correlation coefficient values of the QSAR models. In molecular properties, molecular weight in combination with energies of frontier orbitals, electronegativity, and hardness provides better result. The predicted activities as calculated by molecular properties have been found to be very close to the observed activity.