Bivalence metal complexes of antithyroid drug carbimazole; synthesis, characterization, computational simulation, and biological studies

Abstract

New metal complexes of carbimazole (CMZ) were synthesized with a molar ratio of 1:2. The bivalence complexes were characterized by various techniques, such as elemental analyses and UV–visible spectra, magnetic, and thermal analysis. The metal-ligand stability constant obtained from the molar ratio experiment showed high copper complex stability among the prepared metal compounds at room temperature (Kf =6.6 × 105). The infrared spectra (IR) showed that the CMZ ligand coordinated to the metal through the sulfur atom and the oxygen ether group. The spectroscopic results suggested tetrahedral geometry for all complexes except Ni(II) and Zn(II) complexes with a square planar arrangement. The proposed structures were optimized using density functional theory (DFT/B3LYP) and 6–311G*(d,p) basis sets. The geometrical optimization parameters and molecular electrostatic potentials were calculated. Biological investigation started with DNA binding spectroscopy, which revealed a high binding ability of the Cu(II) and Ni(II) complexes to the CT-DNA. A docking study using different protein receptors was implemented to study the proposed drug's molecular behavior. The in vitro cytotoxicity evaluation of the complexes toward breast human cancer (Mcf7) and human colon cancer (CaCo-2) cell linesindicated that the Cu(II)-CMZ complex has high potential anticancer activities against those cell lines.