Synthesis, characterization, and superoxide dismutase activity of copper(II) complexes with bidentate ligands

Abstract

Two new copper(II) complexes, [Cu(BH)(bipy)](ClO4)2(H2O)2 (1) and [Cu(BH)2(NO3)2] (2) (BH = benzoylhydrazine, bipy = 2,2′-bipyridine), have been synthesized and characterized. X-ray crystallographic analysis shows the copper to be four- and six-coordinate in the complexes. The magnetic and spectroscopic data indicate a distorted square-planar geometry for 1, while 2 is assigned a distorted octahedral geometry. The electron paramagnetic resonance spectra indicate a ground state (g ‖ > g ⊥ > 2.0023). Both complexes display quasireversible redox waves due to Cu(II)/Cu(I) reduction. The superoxide dismutase-mimetic activity of the complexes was investigated by nitro blue tetrazolium chloride DMSO assay.