3,5-Dimethyl-1,3,5-oxadiazinan-4-one

3-(hydroxymethyl)-1,1-dimethylurea

7,9-二氢-7,9-二甲基-1H-嘌呤-2,6,8(3H)-三酮

3-甲基-2H-1,3-苯并恶嗪-2,4(3H)-二酮

2,2-bis(dimethylcarbamoylamino)acetic acid