Synthesis, characterization, DFT calculation, biological and molecular docking of Cu(II) complex of pyrimidine derived Schiff base ligand

Abstract

Biologically active Cu(II) complex was synthesized from pyrimidine based Schiff base ligand 4-choloro-2-(((4,6-dimethoxypyrimidin-2-yl)imino)methyl)phenol. The prepared ligand and its Cu(II) complex were characterized by analytical and spectroscopic techniques. Molar conductance result suggests that prepared Cu(II) complex has non-electrolytic nature. Elemental and ESI-MS spectroscopic result shows that stoichiometry of ligand and Cu(II) complex are 1:1 ratio. Spectroscopic results reveal that proposed structure of Cu(II) complex possess square planar geometry. The molecular geometry of ligand and its complex were studied by DFT calculation. Antimicrobial activity of prepared compounds was screened against Bacillus subtilis (B. subtilis), Escherichia coli (E. coli) and Staphylococcus aureus (Stap. aureus), Aspergillus niger (A. niger), Candida albicans (C. albicans) and Mucor indicus (M. indicus). These results suggest that Cu(II) complex has better antimicrobial activity than ligand. Moreover, the prepared compounds are highly active in B. subtilis bacteria and C. albicans fungi than other microorganisms. Antioxidant activity of prepared compounds were studied by DPPH assay results recommends that Cu(II) complex has better antioxidant activity than ligand. DNA binding nature of prepared compounds with calf thymus (CT) DNA was performed by electronic absorption and viscometric measurements. The result exposed that prepared compounds can interact with CT-DNA through an intercalation mode. BSA binding ability of prepared compounds were studied by electronic absorption technique and the results shows that prepared compounds posses quenching ability with BSA molecules. Furthermore, molecular docking of prepared compounds were investigated with DNA and BSA, and the result suggests the Cu(II) complex has better binding nature than ligand.