1,3-二甲基脲

1,3-dimethyl-7-mercaptopyrido[2,3-d]pyrimidine-2,4-(1H,3H)-dione

6-acetyl-1,3-dimethylpyrido[2,3-d]pyrimidine-2,4,7(1H,3H,8H)-trione

6-cyano-1,3-dimethylpyrido[2,3-d]pyrimidine-2,4,7-(1H,3H,8H)-trione

6-nitropyridopyrimidine