Design, Syntheses, Characterization And Superoxide Dismutase Activity Of Scorpionate Transition Metal Complexes With Aliphatic Dicarboxylate Acids

Superoxide dismutase enzyme (SOD) is a kind of metalloenzyme, which ubiquitous in living systems. These enzymes serve a vital role in defending oxygen-utilizing life forms from oxidative damage which is the byproduct of aerobic metabolism. Due to the limitations of enzyme therapies, such as high cost, short lifetime and tissue impermeability, etc, chemical synthesis of the high efficient, low-toxic metal complexes (SOD mimics compounds) which catalyze the dismutation of O2-·have become one of the most active areas of biochemical research.The rational design and syntheses of high selective and efficient catalysts which mimic a natural enzyme activity center is the most significant problem of many chemists. So it is important to choose appropriate ligands in preparing SOD mimics complexes. Scorpionate ligands can occupy three coordination sites on the central metal, the remaining coordinate sites can bind small molecules for modifying or controlling properties of the complexes. On the other hand, aliphatic a,ε-dicarboxylic acids are of special interest because of their versatile coordination modes and conformational flexibility which have been widely employed in coordination chemistry.The syntheses, structures and properties of metal complexes with poly(pyrazolyl)borate and carboxylate ligands are our mainly work. In this paper, we synthesize 12 complexes. Their structures are determined by X-ray single crystal diffraction. All the complexes are characterized by elemental analysis, IR spectra and UV-vis spectroscopy. In addition, thermal analysis for complexes 2-9 (except 8) and quantum chemistry calculations for complexes 1-12 (except 8) were also performed for analyzing the stabilization of them. Note:sue = succinic acid, Hglu = glutaric acid, ad = adipic acid, sub = suberic acid, Haze = azelaic acid, seb = sebacic acid, HTA = tetradecane diacid.