Synthesis, Characterization, Pharmacological Screening, Molecular Docking, DFT, MESP, ADMET Studies of Transition Metal(II) Chelates of Bidentate Schiff Base Ligand

The synthesis of four transition metal(II) complexes were carried out from bidentate Schiff base ligand which further characterized by numerous spectral and analytical techniques. The synthesized compounds were examined against pharmacological activities and the obtained results were supported by the molecular docking, DFT, MESP and ADMET studies. [Display omitted] •Synthesis and characterization of Co(II), Ni(II), Cu(II) and Zn(II) metal complexes of bidentate Schiff base ligand.•In vitro antioxidant, anti-inflammatory and antibacterial studies of the compounds were performed.•The more biological efficiency of the nickel(II) complex (3) was advocated by the pharmacological studies.•The highest activity of the complexes was supported by molecular docking, DFT, MESP and ADMET studies. The death causing infectious diseases are increased very rapidly, therefore, to find out a significant agent for these ailments, a family of four transition metal complexes were synthesized from a heterocyclic Schiff base ligand by condensing 3,4-dihydro-2H-benzo[b][1,4]dioxepin-7-amine with 5-nitrosalicylaldehyde and characterized them by numerous analytical techniques i.e. 1H NMR, 13C NMR, UV–vis, FTIR, TGA, mass spectrometry, molar conductance, SEM, powder XRD, TGA, elemental inspection and magnetic susceptibility for structure elucidation. The characterization data suggested the coordination of ligand with central metal atom in bidentate manner forming octahedral geometry. The non-electrolytic property of the compounds was demonstrated by the molar conductivity values and thermal data suggested that compounds decompose in three steps leaving metal oxide as residue. The DPPH and egg albumin assays were implemented to know the antioxidant and anti-inflammatory properties of the compounds, respectively while the antibacterial (against S. aureus and E. coli) activity was evaluate by serial dilution and agar well diffusion assays. The performed pharmacological activities revealed that the biological efficiency of the ligand was enhanced on chelation and the nickel(II) complex (3) is more potent among the synthesized compounds for oxidant, inflammation and bacterial pathogens. Further, the biological efficacy of the complexes was validated by computational techniques like molecular docking (against 1GAL, 2AZ5, 1HNJ), DFT, MESP and ADMET studies which states that the complex (3) is highly potent and may be used as potential drug for pathogen causing deformities.