Preparation, spectroscopic, thermal and molecular docking studies of covid-19 protease on the manganese(II), iron(III), chromium(III) and cobalt(II) creatinine complexes

Abstract

ABSTRACT. Creatinine biomolecule has three different coordination modes through the (exocyclic O(5) and ring N(1)), (imine N(2) and ring N(1)) or as monodentate ligand via exocyclic O(1)). The FTIR and electronic spectra of the synthesized manganese(II), iron(III), chromium(III), and cobalt(II) complexes consistent with the coordinated behavioral derived from the structural analyses. Thermogravimetric data agree with the stoichiometry and proposed formulas [Mn(C4H7N3O)2(Cl)2]4H2O, [Fe(C4H7N3O)2(Cl)2]Cl.6H2O, [Cr(C4H7N3O)2(Cl)2]Cl.6H2O, and [Co(C4H7N3O)2(Cl)2]6H2O. Four new transition metal complexes derived from the reaction of creatinine chelate and metal salt (MnCl2.4H2O, FeCl3.6H2O, CrCl3.6H2O, and CoCl2.6H2O), were prepared with 1:2 (metal: ligand) stoichiometry, isolated and well characterized by a different spectral and analytical techniques including FTIR, UV/Vis, magnetic susceptibility, molar conductance, elemental analysis, and TGA/DrTGA/DTA. The solid complexes were formed with the binding of the creatinine ligand through exocyclic O(5) and ring N(1) and presented as an octahedral geometry. In addition molecular docking calculations have been performed between complexes of manganese(II), iron(III), chromium(III) and cobalt(II) with creatinine biomolecule ligand with the Covid-19 protease (6LU7) to determine the best binding site and its inhibitory effect.                     KEY WORDS: Creatinine, Coordination, Transition metals, TGA/DTA, Octahedral geometry   Bull. Chem. Soc. Ethiop. 2021, 35(2), 399-412. DOI: https://dx.doi.org/10.4314/bcse.v35i2.13