A computational study of the binding of 3-(arylidene) anabaseines to two major brain nicotinic acetylcholine receptors and to the acetylcholine binding protein
作者:Svetoslav H. Slavov、Maksim Radzvilovits、Susan LeFrancois、Iva B. Stoyanova-Slavova、Ferenc Soti、William R. Kem、Alan R. Katritzky
DOI:10.1016/j.ejmech.2010.02.027
日期:2010.6
Nicotinic acetylcholine receptors (nAChRs) have become targets for drug development in recent years. 3-(2,4-dimethoxybenzylidene)-anabaseine (DMXBA), which selectively stimulates the alpha 7 nAChR, has been shown to alleviate some cognitive deficits associated with schizophrenia. In this paper we report an analysis of the interactions between 47 arylidene-anabaseines (including 45 benzylidene-anabaseines) and rat brain alpha 7 and alpha 4 beta 2 nicotinic acetylcholine receptors, using three different modeling techniques, namely 2D-QSAR, 3D-QSAR and molecular docking to the Aplysia californica acetylcholine binding protein (AChBP), a water soluble, homomeric nAChR surrogate receptor with a known crystal structure. Our investigation indicates the importance of; (1) the nitrogen atom of the tetrahydropyridyl (THP) ring for hydrogen bond formation; (2) pi-pi interactions between the aromatic rings of the ligands and the nAChBP binding site; (3) molecular surface recognition expressed in terms of steric complimentarity. On the basis of the 3D-QSAR results, bulky substituents at positions 2 (and due to the rotational freedom also at position 6) and 4 of the benzylidene moiety, with highly electronegative atoms projecting approximately 3-3.5 angstrom away from the benzylidene ring at position 4 seem optimal for enhancing binding affinity to the alpha 7 nAChR.