6-(but-2-enylamino)-1,3-dimethylpyrimidine-2,4-dione

1,3,6-trimethylpyrido[2,3-d]pyrimidine-2,4-dione

6-hydroxy-1,3-dimethyl-9H-pyrimido[4,5-b]indole-2,4-dione

6-methoxy-1,3-dimethyl-9H-pyrimido[4,5-b]indole-2,4-dione

1,3-dimethyl-6-phenylpyrimidine-2,4-dione