Synthesis, characterization, DNA interaction and antibacterial activities of two tetranuclear cobalt(II) and nickel(II) complexes with salicylaldehyde 2-phenylquinoline-4-carboylhydrazone

Salicylaldehyde 2-phenylquinoline-4-carboylhydrazone (H2L), and its novel tetranuclear cobalt(II), nickel(II) complexes have been synthesized and characterized. The crystal structure of (NiL)2·[NiL(H2O)(DMF)]2·H2O·DMF obtained from DMF solutions of compound 2 was determined by X-ray diffraction analysis. The DNA-binding investigation suggests that the two complexes bind to DNA via groove binding mode. The in vitro antibacterial activity of complexes against Escherichia coli, Staphylococcus aureus, Bacillus subtilis was screened and compared to the activity of the free ligand, the antibacterial activity of complex 1 is active than complex 2 which is in consistent with their DNA-binding behaviors.