4-羟基-6-氧代-1,6-二氢-5-嘧啶甲酰胺

6-氯嘧啶-2(1H)-酮

5-氰基尿嘧啶

2-benzylsulfanyl-1H-pyrimidin-6-one

3'-O-acetyl-2'-deoxy-5'-O-triphenylmethyluridine