https://doi.org/10.1351/goldbook.09968
Flavones and 3-hydroxyflavones (flavonols) are compounds with a 2-phenyl-4\(H\)-1-benzopyran-4-one (2-phenyl-4\(H\)-chromen-4-one) skeleton 5.
Note: The term "flavonol" is used as a class name for compounds with a 3-hydroxy-2-phenyl-4\(H\)-1-benzopyran-4-one (3-hydroxy-2-phenyl-4\(H\)-chromen-4-one) skeleton 6.
Source:
PAC, 2018, 90, 1429. 'Nomenclature of flavonoids (IUPAC Recommendations 2017)' on page 1432 (https://doi.org/10.1515/pac-2013-0919)
PAC, 2018, 90, 1429. 'Nomenclature of flavonoids (IUPAC Recommendations 2017)' on page 1432 (https://doi.org/10.1515/pac-2013-0919)