Ozonization of Thio- and Azauracils

Abstract

Abstract The reactions of 2-thiouracils and azauracils with ozone have been examined. 2-Thiouracils were ozonized to give the corresponding 4(3H)-pyrimidinones and uracils. Ozone attacks the thiocarbonyl moiety and the desulfurization process to give 4(3H)-pyrimidinones competes with the oxidation process to give uracils. 5-Azauracil was stable for ozone, while 6-azauracil readily reacted with ozone to give parabanic acid.