8-(1,4-dioxan-2-yl)-1,3-dimethyl-7H-purine-2,6-dione

8-(1-ethoxyethyl)-1,3-dimethyl-7H-purine-2,6-dione

N-甲基-4-(甲基氨基)-1H-咪唑-5-甲酰胺

7-氨基-1,3-二甲基-3,7-二氢-1H-嘌呤-2,6-二酮

4-(1,3-dimethyl-2,6-dioxopurin-7-yl)butanenitrile