Synthesis, structural elucidation, DFT investigations, biological evaluation and molecular docking studies of tetraamide-based macrocyclic cobalt (II) complexes.

A new series of 16–18 membered cobalt (II) macrocyclic complexes derived by 3,4-diaminobenzophenone have been synthesized. The elemental analysis, FT-IR, 1H NMR, 13C NMR, mass spectrometry, UV–visible, ESR, thermogravimetric analysis, PXRD, SEM studies and DFT analysis were used to characterize these synthesized tetraamide macrocyclic ligands and their cobalt (II) complexes. DFT (density functional theory) calculations were used to calculate quantum chemical parameters. The octahedral geometry of all the complexes has been proposed by DFT and experimental evidences. The synthesized ligands and their cobalt (II) complexes were tested for their in vitro antimicrobial and scavenging activities. Antibacterial activity of synthesized compounds was tested against S. Marcescence, E. coli and S. aureus. The A. Flavus, G. Candidum, F. oxysporum were tested for antifungal properties. The DPPH method was used to further screen the tetraamide macrocyclic ligands and their Co(II) macrocyclic complexes for their in vitro antioxidant properties. Moreover, the complexes are highly active against E. coli bacteria and A. flavus fungi than other microorganisms. The results are well corroborated with molecular docking studies. Furthermore, the purpose of the molecular docking studies was to better understand how these compounds interact with biomolecules. [ABSTRACT FROM AUTHOR]