Structure and antioxidant superoxide dismutase activity of copper(II) hydrazone complexes. (28th January 2017)

• Record Type: Journal Article
• Authors: Singh, Yogendra Pratap; Patel, Ram N.; Singh, Yogendra; Butcher, Ray J.; Vishakarma, Pradeep Kumar; Singh, R.K. Bhubon
• Is Part Of: Polyhedron. Volume 122(2017)
• Page Start: 1
• Page End: 15
• Publication Date: 2017-01-28
• Subjects: Mixed ligand complexes -- Antioxidant SOD mimics -- X-ray analysis -- Electron paramagnetic resonance(epr) spectra -- Cyclic voltammetry (CV); Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2016.11.013
• Languages: English
• ISSNs: 0277-5387

Abstract

Graphical abstract: Three new copper(II) complexes have been synthesized and characterized using various physico-chemical techniques. The structures of the complexes have been determined by single crystal X-ray diffraction analysis. Antioxidant SOD activity tests showed that copper(II) complexes possess significant scavenging effect against free radicals. Abstract: Three new mixed ligand hydrazone complexes viz., [Cu(L)(neocuprin)]NO3 ·H2 O1, [Cu(L)(HL)]ClO4 2 and [Cu2 (2-(2-pyridyl)benzimidazole)2 (L)2 ]ClO4 3 (L = N ′-[( E )-phenyl(pyridin-2-yl)methylidene]furan-2-carbohydrazide) have been synthesized by the biomimetic synthesis strategy and their structures were determined by single crystals X-ray analysis. The effect of differing contagious, as well as the rotational conformational versatility of HL, was demonstrated by the difference in structures of complexes1 –3 . These complexes exhibited the antioxidant superoxide dismutase enzymatic activity. The geometry of copper(II) atom in complex1 is distorted square pyramidal while in complexes2 and3 the geometries around copper(II) atoms are distorted octahedral. Magnetic measurements and epr spectroscopy of binuclear complex3 have shown antiferromagnetic exchange interaction with a coupling constant ( J ) = −10.87 cm −1 . Electronic and spectral properties of these newly synthesized hydrazone complexes (1 –3 ) are interpreted by DFT and TDDFT calculations. The results reveal that molecular structures have significant effect on antioxidant superoxide activity. Such biological experimental values (antioxidant SOD activity data) are indicative of the promising application of these complexes into the bioinorganic chemistry of superoxide dismutase.