Fig. 2.
Formation of major products from the reaction of peroxynitrite and guanine residue. The reaction between peroxynitrite (ONOO−) and guanine (G) residue forms 8-nitroguanine (8-nitroG), 8-oxoguanine (8-oxoG), 5-guanidino-4-nitroimidazole (NI) and 2,5-diamino-4H-imidazol-4-one (Iz) and it undergoes hydrolysis to form 2,2,4-triamino-5(2H)-oxazolone (Oz) at physiologic pH