1,3-dimethyl-8-morpholin-4-yl-7H-purine-2,6-dione

1,3-dimethyl-8-piperidin-1-yl-7H-purine-2,6-dione

5-氨基-1,3-二甲基嘧啶-2,4(1H,3H)-二酮

1,3-dimethyl-5-formylaminopyrimidine-2,4-dione

1,3-dimethylpyrido[3,2-d]pyrimidine-2,4(1H,3H)-dione