5-(2'-benzothiazolylhydrazono)-1,3-dimethylbarbituric acid

1,3-二甲基-2,4,5,6(1H,3H)-嘧啶四酮 5-肟

咖啡因

1,3-二甲基-1,3-二嗪农-2,4,5,6-四酮

5,5-dichloro-1,3-dimethyl-1,3-diazinane-2,4,6-trione