Novel 1,3‐diphenyl‐4‐(N,N‐dimethylimido dicarbonimidic diamide azo)‐5‐pyrazolone and its chelates with manganese, nickel, copper, and zinc divalent metal ions as an antibacterial activity supported by molecular docking studies: Design, synthesis, DFT, and TD‐DFT/PCM calculations

Abstract

A novel 1,3‐diphenyl‐4‐(N,N‐dimethylimidodicarbonimidic diamide azo)‐5‐pyrazolone as a ligand, simplified as DNP, and its chelates were prepared. Characterization of the structures was performed based on several analytical and spectroscopic techniques. To support these studies, density functional theory (DFT) calculations were carried out by using the B3LYP level, B3LYP/6‐311G** level for the free ligand, and B3LYP/6‐311G**‐LANL2DZ functional level for the solid chelates. The acquired results indicated that DFT calculations generally give compatible results with the experimental ones. Hyper conjugative interactions, molecular stability, bond strength, and intramolecular charge transfer were examined by applying natural bond orbital (NBO) analysis. Nonlinear optical properties of the obtained compounds were investigated by determining molecular polarizability (α), and hyperpolarizability (β) parameters provided a hint for the synthesized compounds' intriguing optical characteristics. The electronic structure of the ligand and its complexes were predicted using the time‐dependent DFT (TD‐DFT) method with a polarizable continuum model (PCM) exploiting the B3LYP approach combined with a 6‐31G(d,p) basis set. The prepared compounds' antibacterial activity was experimentally verified utilizing the agar well diffusion method versus selected G + and G‐ bacteria. The molecular docking mechanism between the bacterially resistant chelates and their inhibited bacteria protein pocket receptors was carried out to determine the modes that these compounds bind to the protein's active sites.