Quantitative structure-activity relationship studies for antioxidant hydroxybenzalacetones by quantum chemical- and 3-D-QSAR(CoMFA) analyses.

Antioxidant activities for a series of hydroxybenzalacetones, OH-BZ, evaluated by their inhibitory potencies against lipid peroxidation induced by gamma-ray irradiation or t-BuOOH, were analyzed quantitatively using quantum-chemical parameters calculated by semi-empirical molecular orbital (MO) calculations. The energy of the highest occupied molecular orbital (E(HOMO)) and frontier electron densities (HOMO) on the phenolic oxygen atom (F(H,O)), together with the steric parameter (E(s)) for the substituent ortho to the phenolic oxygen, showed excellent correlations. We also performed 3D-QSAR studies by using the comparative molecular field analysis (CoMFA) model. The results were compared with the corresponding classical QSAR correlations.