6-氨基-5-甲酰氨基-1,3-二甲基尿嘧啶

2,4-bis(dimethylamino)-10-imino-7,9-dimethyl-1,7,9-triazaspiro[4.5]deca-1,3-diene-6,8-dione

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

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

1,3-dimethyl-8-(6-oxocyclohexa-2,4-dien-1-ylidene)-7,9-dihydropurine-2,6-dione