Isoflavonoids

thumb|3-phenylchromen-4-one thumb|3-phenylchroman (isoflavan) backbone of the isoflavanes Isoflavonoids are a class of flavonoid phenolic compounds, many of which are biologically active. Isoflavonoids and their derivatives are sometimes referred to as phytoestrogens, as many isoflavonoid compounds have biological effects via the estrogen receptor.