Flavonoids, cinnamic acids and coumarins from the different tissues and medicinal preparations of Taraxacum officinale.

Three flavonoid glycosides: luteolin 7-glucoside and two luteolin 7-diglucosides were isolated from dandelion flowers and leaves together with free luteolin and chrysoeriol in the flower tissue. The hydroxycinnamic acids, chicoric acid, monocaffeyltartaric acid and chlorogenic acid were found throughout the plant and the coumarins, cichoriin and aesculin were identified in the leaf extracts. This represents the first report of free chrysoeriol (luteolin 3'-methyl ether) in Taraxacum officinale agg. An earlier provisional identification of chicoric acid, chlorogenic acid, cichoriin and aesculin in a phenolic survey of the tribe Cichorieae is confirmed. Chicoric acid and the related monocaffeyltartaric acid were found to be the major phenolic constituents in flowers, roots, leaves and involucral bracts and also in the medicinal preparations tested.