5-Acetyluracil (CAS No.6214-65-9), its synonyms are 2,4(1H,3H)-Pyrimidinedione, 5-acetyl- ; 5-Acetylpyrimidine-2,4(1H,3H)-dione ; 5-Acetyl-1H-pyrimidine-2,4-dione ; 5-Acetyl-2,4(1H,3H)-pyrimidinedione .