Novel bio-essential metal based complexes linked by heterocyclic ligand: Synthesis, structural elucidation, biological investigation and docking analysis

Abstract

New series of bio-essential metal based complexes linked by Schiff base ligand (L) and 2,2′-bipyridine (bpy) have been synthesized and characterized by diverse spectral techniques such as elemental analysis, magnetic susceptibility, molar conductivity measurements, FT-IR, UV–Vis., 1H NMR, 13C NMR, EPR and Mass. The spectral data suggest that the metal complexes espouse octahedral geometry around the metal ions. Interactions of the complexes with CT DNA have been explored by electronic absorption, ethidium bromide displacement assay, viscosity measurements, cyclic voltammetry and differential pulse voltammetry in order to evaluate the possible DNA-binding mode and to calculate the corresponding DNA-binding constants. The DNA interaction studies propose that the intercalative mode of interaction and the complexes exhibit oxidative cleavage of pUC19 DNA in the presence of hydrogen peroxide as activator. The synthesized Schiff base ligand and its metal complexes have been screened for anti-microbial activity by micro dilution method against two Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis), two Gram-negative bacteria (Escherichia coli and Salmonella typhi) and three fungi strains (Fusarium solani, Aspergillus niger and Candida albicans) revealing that the complexes are good anti-pathogenic agents than the ligand. Moreover, molecular docking analysis has been performed to confirm the nature of binding of the complexes with DNA.