Oxidation of Zn(N2S2) complexes to disulfonates: relevance to zinc-finger oxidation under oxidative stress

A series of Zn(N2S2) complexes has been prepared, and characterized. They have different nitrogen donors such as, either two amidates, two amines, two imines or one amidate and one imine. A bis-amidato dithiolato complex has been structurally characterized by single crystal X-ray diffraction analysis, and exhibits a distorted tetrahedral structure. Oxidation of all these complexes with dioxirane or anhydrous H2O2 results in the formation of a unique product, the disulfonate species. Most often, zinc was found to be released during the course of the oxidation. The bis-imine/bis-sulfonate species is the only one to retain zinc. This complex was crystallized with two pyridine molecules. Its crystal structure reveals a distorted octahedral environment around the zinc cation.