Theoretical study: Electronic structure and receptor interaction of four type bis-1,4-dihydropyridine molecules.

The structure of four type bis-1,4-dihydropyridine molecules was completely optimized employing semiempirical (PM3), ab initio (HF/3-21G(d), B3LYP/6-31G(d) and B3LYP/6-311++G(d,p) methods. The B3LYP/6-311++G(d,p) theory level provided a flat boat conformation. The observed ring distortions were not found to be influenced to a great extent by the position of the substituent present in the 4-phenyl ring, the second dihydropyridine ring. The HOMO, LUMO, chemical hardness, global softness, chemical electrophilicity and molecular electrostatic potential values were also appropriately calculated. The electronic parameters allowed to establish the reactivity of the four bis-1,4-dihydropyridine molecules. Moreover, the interactions between these compounds with two models of the voltage-gated calcium channel receptor were evaluated in connection to the reported vasodilator activity of these compounds.