. 2018 Mar 14;58(1):5–25. doi: 10.1007/s00394-018-1663-8

Table 1.

Flavonoid subclasses and their dietary sources

Flavonoids	C ring functional group	Dietary source	Compound	Chemical formula
Anthocyanidins	3-Hydroxy	Cherry, berries, and red wine	Cyanidin Delphinidin Malvidin Pelargonidin Petunidin Peonidin	C₁₅H₁₁O₆+ C₂₇H₃₁O₁₇+ C₁₇H₁₅O₇+ C₁₅H₁₁O₅+ C₁₆H₁₃O₇+(Cl−) C₁₆H₁₃O₆+
Flavones	4-Oxo	Carrots, olive oil, peppers, rosemary peppermint, and celery	Apigenin Luteolin	C₁₅H₁₀O₅ C₁₅H₁₀O₆
Flavan-3-ols	3-Hydroxy 3-O-gallate	Tea, chocolate and cocoa	(+)-Catechin (+)-Gallocatechin (−)-Epicatechin-3-gallate (−)-Epigallocatechin-3-gallate	C₁₅H₁₄O₆ C₁₅H₁₄O₇ C₂₂H₁₈O₁₀ C₂₂H₁₈O₁₁
Flavonols	3-Hydroxy, 4-Oxo	Onion, olive oil, and berries	Fisetin Isorhamnetin Kaempferol Myricetin Quercetin	C₁₅H₁₀O₆ C₁₆H₁₂O₇ C₁₅H₁₀O₆ C₁₅H₁₀O₈
Flavanones	4-Oxo	Citrus fruits	Hesperetin Naringenin	C₁₆H₁₄O₆ C₁₆H₁₄O₅
Isoflavones	4-Oxo	Soy bean and leguminous plants	Daidzein Genistein Glycitein Biochanin A Formononentin	C₁₅H₁₀O₄ C₁₅H₁₀O₅ C₁₆H₁₂O₅ C₁₆H₁₂O₅ C₁₆H₁₂O₄