New nanometric metal complexes based on thiazole derivative as potential antitumor and antimicrobial agents: Full structural elucidation, docking simulation and biological activity studies

Abstract

Novel Mn(II), Ni(II), Zr(IV) and Cd(II) nanosized complexes of thiazole Schiff base derivative (HL) were synthesized for further medicinal applications. The inspected complexes were fully characterized using elemental and thermal analyses in addition to infrared spectroscopy (IR) and nuclear magnetic resonance (1HNMR). Electronic absorption spectra, X-ray powder diffraction (XRD), transmittance electron microscopy (TEM), molar conductance and magnetic moment were also measured and explained. The brought about data revealed that the ligand–metal chelation happened through the N atom of N = N group, and the ortho-dehydrogenated phenolic O atom to form the chelates where the metal binds with one molecule of the parent ligand. All applied spectroscopic and analytical techniques confirmed tetrahedral geometry in Mn(II) and Ni(II) complexes and octahedral geometry for Cd(II) and Zr(IV) complexes. The ligand, Mn(II), Ni(II), and Zr(IV) chelates' XRD patterns indicated an amorphous character where the Cd(II) complex's nature is crystalline. Transmission electron microscopy (TEM) images of the prepared compounds showed that the surface morphology is uniform and homogeneous. Also, the metal ions distribute through the complexes' surface in a nanosized nature. The metal complexes have been simulated by docking in the co-crystal structures of the liver cancer and breast cancer proteins with PDB IDs, 2JW2 and 3S7S, successively. Antibacterial, antifungal and anticancer activities for the ligand that has been produced and its complexes were achieved. The most encouraging antitumor results were acquired by Ni(II) chelate which exhibited an IC50 of 23.52 µg/ml contra MCF-7 cells (human breast cancer) which is lower than the reference 5-Fluorouracil (5-FU, IC50 = 28.00 µg/ml).