Daraus:
Based on their chemical structure, flavonoids can be subclassified into six principal subclasses: flavonols (mainly including quercetin, kaempferol, myricetin, and isorhamnetin), flavones (apigenin and luteolin), flavanones (hesperetin and naringenin), flavan−3-ols (catechin, epicatechin, epigallocatechin, epicatechin−3-gallate, and epigallocatechin−3-gallate), anthocyanins (cyanidin, delphinidin, malvidin, pelargonidin, petunidin, and peonidin), and isoflavones (genistein and daidzein.