3,7-Dihydro-2-thio-4H-pyrrolo[2,3-d]pyrimidin-4-one3,7-Dihydro-2-mercapto-4H-pyrrolo[2,3-d]pyrimidin-4-one3,7-Dihydro-2-sulphanyl-4H-pyrrolo[2,3-d]pyrimidin-4-oneNSC 259761,2,3,7-Tetrahydro-2-thioxo-4H-pyrrolo[2,3-d]pyrimidin-4-one7-Deaza-6-hydroxy-2-mercaptopurine2-Thioxo-7-deazahypoxanthine7-Deaza-2-mercapto-hypoxanthine