Molecular docking and Antibacterial activities of Cobalt (II) complexes derived from precursors of Hydrazones

Abstract

The Schiff base ligands in their deprotonated forms have been utilized to synthesize thermodynamically and kinetically stabilized Cobalt(II) complexes. In the complexes, cobalt ion present is in distorted octahedral arrangement and is coordinated by four tridentate ligands in complexes. The synthesized Schiff base ligands coordinate with Cobalt (II) ion through four azomethine nitrogen atoms and two sulfur atoms developing a 6- membered chelate ring. Synthesized Cobalt(II) complexes via hexadentate ligands have been characterized thoroughly through various spectroscopic techniques like FT-IR, UV-Vis, 1HNMR, TGA, TEM, SEM, Particle size, Elemental analysis (C, H, N, Co, S) and conductivity measurements. All Cobalt(II) complexes have been evaluated for in vitro antimicrobial activity against isolated bacterial strains of E. coli (MTCC-1687), E. faecalis (MTCC-439), S. aureus (MTCC-737) and MR S. aureus (Indigenous). All Cobalt complexes show mild to moderate antibacterial activity. The MIC ranged from 50 µg/ mL to 3.125 µg/ mL. All Cobalt(II) complexes displayed in-vitro antibacterial activity against both gram-positive and gram-negative bacterial strains. It may be proved that the antibacterial activity of the complexes is related to the cell wall structure of the tested bacteria. In-vitro toxicity tests explained the Cobalt complexes were less cytotoxic than the Vancomycin drug on A431 cancer cell lines and the results explain that synthesized Cobalt complexes can act as potent antimicrobial agents and can be considered as a good drug candidate for medicinal chemistry researchers.