Abstract: In this paper, two kinds of 3D-QSAR techniques: comparative molecular fields analysis (CoMFA) and comparative similarity indices analysis (CoMSIA) were applied using a data set of 37 melatonin antagonists. The influences of different grid spacing and partial charge models were systematically investigated. The CoMFA contour plots identified several essential features including steric and electrostatic fields, which are valuable for us to take insight into the mechanisms of the intermolecular interactions between inhibitors and receptor.

Key words: Melatonin, Antagonist, 3D-QSAR, CoMFA, CoMSIA