title: An ESR study of nonenzymatic reactions of nitroso compounds with biological reducing agents.
abstract: The nonenzymatic reduction of nitrosobenzene (I), 2-nitroso-1-naphthol (II) and 2-nitroso-1-naphthol-4-sulfonic acid (III) with reducing agents such as NADPH, L-cysteine and N-acetyl-L-cysteine led to the formation of the corresponding hydronitroxide radicals, as confirmed with ESR spectroscopy. In addition to these radicals, a novel hydronitroxide radical, which was conjugated with GSH at the 4-position, was observed in the reaction of II or III with GSH. The formation of a hydronitroxide conjugated with GSH still retains the radical structure with its related redox chemistry. In this case, the formation of a GSH conjugate does not lead to the formation of chemically less reactive species.
authors.affiliation: Laboratory of Molecular Biophysics, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709.
authors.forename: N
authors.initials: N
authors.lastname: Takahashi
authors.forename: V
authors.initials: V
authors.lastname: Fischer
authors.forename: J
authors.initials: J
authors.lastname: Schreiber
authors.forename: R P
authors.initials: RP
authors.lastname: Mason
mesh_terms: D000111:Acetylcysteine; D055598:Chemical Phenomena; D002621:Chemistry; D003545:Cysteine; D004578:Electron Spin Resonance Spectroscopy; D005978:Glutathione; D009249:NADP; D009282:Naphthalenesulfonates; D009603:Nitroso Compounds; D010084:Oxidation-Reduction
chemical_list: D009282:Naphthalenesulfonates; D009603:Nitroso Compounds; D009249:NADP; C025341:1-nitroso-2-naphthol; C034787:2-nitroso-1-naphthol-4-sulfonic acid; D005978:Glutathione; D003545:Cysteine; D000111:Acetylcysteine; C012456:nitrosobenzene