FLAVONOID P-COUMAROYLGLUCOSIDES AND 8-HYDROXYFLAVONE ALLOSYLGLUCOSIDES IN SOME LABIATAE

The occurrence of flavonoid p-coumaroylglucosides and 8-hydroxyflavone 7-allosylglucosides is restricted, in the Labiatae, to some genera of subfamily Lamioideae (tribe Stachydeae). Generally both types of compounds do not co-occur in the same species. Thus, flavonoid p-coumaroylglucosides are present in all the species studied of the genera Ballota, Phlomis and Marrubium, and are universally present in the subpnus Marrubiastrum of Sideritis, in subpnus Galeopsis and in section Betonica of genus Stachys, while 8-hydroxyflavone 7-allosylglucosides accumulate in the other Sideritis, Stachys and Galeopsis species. Amongst the flavonoid p-coumaroylglucosides, the apigenin derivatives occur most frequently but also the corresponding luteolin, chrysocriol, kaempferol and isorhamnetin glycosides have been detected. The 8-hydroxyflavone allosylglucosides occur as such and also as the monoacetylated and diacetylated derivatives. The presence of p-coumaroylglucosides and/or 8-hydroxyflavone allosylglucosides shows the affinities of Anisomeles, Pogostemon, and Leonurus species with Ballota, Marrubium, Phlomis, Sideritis, Stachys and Galeopsis species. These results suggest that flavonoid p-coumaroylglucosides are valuable markers for chemotaxomic studies.