Metal complexes of Tridentate Schiff base: Synthesis, Characterization, Biological Activity and Molecular Docking Studies with COVID-19 Protein Receptor.

Abstract

Mononuclear chelates of Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Zn(II) and Cd(II) resulted from new tridentate Schiff base ligand, 4-((1-(5-acetyl-2,4-dihydroxyphenyl)ethylidene)amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one, were synthesized. Metal to ligand ratio was found to be1 : 1, which was revealed via elemental analysis and characterized via various spectroscopic tools. IR has point out that the coordination of the ligand towards the metal ions was carried out via NOO donor atoms. UV-Vis, ¹H NMR spectral data, molar conductivity measurements, BET surface area, melting points and theoretically through density function theory were used such as characterizing techniques in supporting further interpretation of the complexes structures. The complexes were octahedral except Cu(II) and Ni(II) complexes were tetrahedral as suggested from the magnetic moment measurement. The complexes were found to have surface area, pore volume and particle radius of 23-176 m² g^-1, 0.02-0.33 cc/g and 8.71-4.32 nm, respectively, as pointed out from BET measurement. Schiff base ligand and metal complexes were tested in vitro to estimate their antimicrobial activity opposed to Gram-negative and Gram-positive bacterial and fungal organisms. MOE 2008 was used headed for screen potential drugs with molecular docking by the protein sites of new coronavirus and the study was constructed to molecular docking without validation through MD simulations.