Free-Radical Chain Oxidation of 2-Nitropropane Initiated and Propagated by Superoxide

摘要

The superoxide radical O2(-), whether produced by the xanthine/xanthine oxidase reaction of infused as KO2, solubilized by a crown ether in dry dimethyl sulphoxide, initiated a free-radical chain oxidation of anionic 2-intropropane. Superoxide dismutase, but not catalase, inhibited oxidation of the nitroalkane. Xanthine oxidase suffered a syncatalytic inactivation, during the co-oxidation of 2-nitropropane, which was reversed by dialysis. Cyanide exacerbated this syncatalytic inactivation and rendered it irreversible. The frequency observed oxidations of nitroalkanes by flavoenzymes now need to be re-examined to clarify the extent to which O2(-)initiated free-radical chain oxidation contributed to the overall nitroalkane oxidation.