Chemotaxonomic studies in the Saxifragaceae s.l. 15. The flavonoids of subsection Villosae section Heuchera in the genus Heuchera

Abstract
The flavonoid constituents of Heuchera villosa var. villosa, H. parviflora var. parviflora, and H. glabra have been studied. The predominant flavonoids present in all three species were mono-, di-, and triglycosides of kaempferol, quercetin, and myricetin. Isorhamnetin, larycitrin, syringetin, and luteolin were also seen in some species. Dihydromyricetin was isolated from H. villosa. The data were compared with results obtained earlier from H. micrantha var. diversifolia and H. cylindrica. The hypothesis that evolutionary advancement and ecological specialization in the genus are accompanied by a simplification in the glycoside pattern was proposed.