Electrochemical and Molecular Docking Studies on the Interactions of (Z)-1-[(2,4-dimethoxyphenylamino)methylene]naphthalen-2(1H)-one with Calf Thymus DNA, HSA and BSA Biomolecules

It is well known that Schiff bases alone have antitumor activity. The necessity of this study is to provide understanding of possible interaction pathways of Schiff bases with some biomolecular targets. So, in the present study, the in vitro interaction characteristics between (Z)-1-[(2,4-dimethoxyphenylamino)methylene]naphthalen-2(1H)-one (DMPAMNON) and some biomolecules (calf thymus deoxyribonucleic acid (ct-DNA), human serum albumin (HSA) and bovine serum albumin (BSA)) at pH of 7.40 were studied by square-wave voltammetry (SWV) and cyclic voltammetry (CV). Cyclic voltammogram of DMPAMNON at Britton–Robinson (B–R) buffer (pH 7.40) exhibited one irreversible cathodic peak at −1.336 V, attributing to the reduction of imine group of (E)-1-[(2,4-dimethoxyphenylimino)methyl]naphthalen-2-ol (enol-imine tautomeric form, abbreviated as DMPAMNOL) resulted from its tautomeric conversion under these experimental conditions. Some electrochemical parameters (E°, ks and αn) of the reduction process were determined and compared to the case with the above-mentioned biomolecules. The obtained electrochemical data verified that DMPAMNOL could interact with these biomolecules by means of the formation of bio-complexes, having a binding stoichiometry of 1 : 1. Their binding constants proved that the interaction between DMPAMNOL and BSA was the strongest. From the molecular docking results, the binding affinities of DMPAMNOL with A-DNA, B-DNA, HSA and BSA were determined as −7.0, −7.6, −7.8, and −8.5 kcal mol−1, respectively. Moreover, except for B-DNA, binding affinity of DMPAMNON is stronger than that of DMPAMNOL.