甲胺

3,8-dimethyl-1-oxa-3,6,8-triaza-spiro[4.4]nonane-2,4,7,9-tetraone

四甲尿酸

8-氯-3,7-二氢-1,3,7-三甲基-1H-嘌呤-2,6-二酮

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