What is "pyrimidone"

n. (context organic compound English) Either of two heterocyclic compounds, with chemical formula C₄H₄N₂O, whose derivatives are the basis of many other biological molecules.

Pyrimidone is the name given to either of two heterocyclic compounds with the formula CHNO: 2-pyrimidone and 4-pyrimidone. The compounds can also be called 2-hydroxypyrimidine or 4-hydroxypyrimidine respectively, based on a substituted pyrimidine, or 1,3- diazine, ring.