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

甲基碘

1,3,7-trimethyl-8-nitropurine-2,6-dione

8-氯-3,7-二氢-1,3,7-三甲基-1H-嘌呤-2,6-二酮

8-hydrazinyl-1,3,7-trimethylpurine-2,6-dione