Co(III), V(IV) and Cu(II) complexes of bidentate N,O‐donor Schiff base ligands: Characterization, anticancer activities and metal oxide nanoparticles preparation via solid state thermal decomposition

Three new mononuclear Schiff base complexes [Co(L 1 ) 3 ( 1 ), VO(L 1 ) 2 ( 2 ) and Cu(L 2 ) 2 ( 3 )] were synthesized, characterized and used as a precursor for preparation of metal oxide nanoparticles. The crystal structure of compounds was determined using single crystal X‐ray diffraction. The Co(III) coordination sphere consists of three phenolato oxygens and three imino nitrogen atoms from three Schiff base ligands, thus forming a distorted octahedral geometry. In complex ( 2 ), the vanadium(IV) is five‐coordinated in a regular tetragonal pyramid fashion and the Cu(II) ion is four coordinated with a square‐planar geometry in the complex ( 3 ). The nanoparticles were characterized by Fourier transform infrared spectroscopy (FT‐IR), X‐ray powder diffraction (XRD) and field emission scanning electron microscopy (FE‐SEM). In vitro cell proliferation via MTT assay was studied to calculate the cytotoxicity of complexes and metal oxide nanoparticles against gastric cancer cell line (MKN‐45). The results showed that all compounds have anticancer activity with dose–response dependency.