Mononuclear cobalt(II), nickel(II) and copper(II) complexes: Synthesis, spectral characterization and interaction study with nucleotide by in vitro biochemical analysis

A series of six novel metal complexes of the type [M(L-1)(2)] 1a-1c and [M(L-2)(2)] 2a-2c, where, M = Cu(II), Ni(II), Co(II), HL1 = 2-(5-(trifluoromethyl)-2-methoxyphenylimino)methyl)-4,6-dichlorophenol and HL2 = 2-(5-(trifluoromethyl)-2-methoxyphenylimino)methyl)-4-bromo-6-methoxyphenol, have been synthesized and characterized by several physicochemical techniques. Having a base of spectroscopic and analytical data, complexes 1a, 1c, 2a and 2c showed a square planar geometry, whereas, complexes 1b and 2b owned a octahedral geometry around the metal ion. Thermal decomposition process of complexes 1a-2c is nonspontaneous, i.e., the complexes are thermally stable. DNA binding (UV-Visible absorption and fluorescence) studies against calf thymus DNA (CT-DNA), revealed an intercalative mode of binding. The complexes along with corresponding ligands have been investigated for their in vitro cytotoxic activity against two human cancer cell lines such as HeLa and A549 using cisplatin as standard drug under MIT assay. All the complexes showed higher cytotoxicity than the parent ligand and moderate to cisplatin. In addition, antimicrobial activity of all the compounds was also examined. (C) 2020 Elsevier B.V. All rights reserved.