Synthesis, characterization and biological activity studies of octahedral nickel(II) complexes

Three nickel(II) complexes, namely [Ni(BH)(3)](H2O)(NO3)(ClO4) 1, [Ni(BH)(2)(NO3)(2)](2) and [Ni(BH)(Tren)](ClO4)(2) 3 (BH = Benzoylhydrazine, Tren = Tris(2-aminoethyl) amine) have been synthesized and characterized by physico-chemical techniques. X-ray crystallographic analysis shows the nickel to be six-coordinated in these complexes. The complexes are efficient catalysts for the dis-mutation of superoxide in alkaline DMSO-NBT assays. The IC50 values are 74,108 and 105 mu M for 1, 2 and 3, respectively.