Synonyms: 4H-Cyclopentapyrimidin-4-one,1,5,6,7-tetrahydro-2-(methylthio)- (9CI); 5H-Cyclopentapyrimidin-4-ol,6,7-dihydro-2-(methylthio)- (6CI,7CI,8CI);2-(Methylthio)-4(3H)-oxocyclopenteno[d]pyrimidine;6,7-Dihydro-2-(methylthio)-5H-cyclopenta[d]pyrimidin-4-ol; NSC 27371