4-Pyrone4-Pyrone is an unsaturated compounds|unsaturated] cyclic chemical compound with the molecular formula C5H4O2.It is isomeric with 2-pyrone.Preparation4-Pyrone is prepared via the thermal decarboxylation of chelidonic acid.Reactions4-Pyrone and its derivatives react with amines in protic solvents to form 4-Pyridones.Derivatives4-Pyrone forms the central core of several natural chemical compounds, including maltol, meconic acid, kojic acid, and of the important class of the flavones.