Flavonoid aglycones from the leaf and stem exudates of some Geraniaceae species.

Six species of Pelargonium and one species of Geranium were studied for their surface flavonoids. Some of them were found to exhibit an unexpectedly high number of methylated flavonoids, mostly flavonols. The chemotaxonomic significance of exudate flavonoid diversification is shortly addressed.

Exudate flavonoids in some Gnaphalieae and Inuleae (Asteraceae).

Three members of the tribe Gnaphalieae and six members of the tribe Inuleae (Asteraceae) were analyzed for their exudate flavonoids. Whereas some species exhibit rather trivial flavonoids, others produce rare compounds. Spectral data of rare flavonoids are reported and their structural identification is discussed.