1,3,4a,4b,6,8-hexamethyl-hexahydro-cyclobuta[1,2-d,4,3-d']dipyrimidine-2,4,5,7-tetraone

4-羟基-2-巯基-5-甲基嘧啶

2-氨基-5-甲基-4-嘧啶醇

N,N'-二甲基-2-甲基丙二酰胺

2,4,6,7,7-pentamethyl-2,4-diazabicyclo[4.2.0]octane-3,5-dione