Synthesis, crystal structure and superoxide dismutase activity of a five-co-ordinated manganese(II) complex

Abstract

A five-co-ordinate manganese(II) complex [Mn(ntb)(Hsal)][ClO₄], where ntb is tris(benzimidazol-2-ylmethyl)amine and Hsal^– is the anion of salicyclic acid (H₂sal), has been prepared and characterized by X-ray crystallography. The manganese adopts a distorted trigonal-bipyramidal co-ordination geometry with a N₄O ligand donor set and bears structural similarities to the active site of manganese superoxide dismutase. The electro-

chemical properties of the complex were studied in MeCN by cyclic voltammetry. The complex can catalyse the dismutation of superoxide (O₂^–) effectively in the riboflavin–methionine–nitro blue tetrazolium assay.