Novel water soluble bis(μ-chloro) bridged Cu(II) binuclear and mononuclear complexes: Synthesis, characterization and biological evaluation

A water soluble chloro bridged binuclear copper(II) complex (3) and mononuclear complex (4) have been synthesized from chloro substituted 2-oxo-1,2-dihydroquinolin-3-yl-methylene-2 hydroxybenzohydrazide 1 and 2 and CuCl₂·2H₂O. The structures of the complexes have been determined by single crystal X-ray diffraction. The binding interactions of the ligands and complexes with CT-DNA and protein have been evaluated by absorption and emission spectroscopic method. CT-DNA and ethidium bromide (EB) competitive studies revealed that the compounds could interact with CT-DNA through intercalation binding mode. Interactions of the compounds with BSA were also studied by UV−visible, fluorescence and synchronous fluorescence spectroscopic methods which showed that the compounds had a strong binding affinity with BSA through static quenching process. The cytotoxic effect of the compounds examined on cancer cell lines, such as A549 (lung cancer) and MCF7 (breast cancer) cell lines showed that all four compounds exhibited substantial cytotoxic activity.