3,5,7-trimethyl-[1,2]oxazolo[3,4-d]pyrimidine-4,6-dione

5,7-dimethyl-3-phenyl-[1,2]oxazolo[3,4-d]pyrimidine-4,6-dione

5,7-dimethyl-[1,2]oxazolo[3,4-d]pyrimidine-4,6-dione

1,3-二甲基-6-甲基氨基-2,4-二羰基-1,2,3,4-四氢嘧啶-5-甲醛

1,3-dimethyl-6-[(triphenyl-λ⁵-phosphanylidene)amino]pyrimidine-2,4-dione