6-thiotheophylline

1,3-Dimethyl-6-thioxo-6,7-dihydro-1H-purine-2(3H)-one

2,3,6,7-Tetrahydro-1,3-dimethyl-6-thioxo-1H-purin-2-one

2H-Purin-2-one, 1,3,6,7-tetrahydro-1,3-dimethyl-6-thioxo-