Flavonoids from seeds of Camellia semiserrata Chi. and their estrogenic activity

Two new flavonol glycosides and three known flavonoids were isolated from seeds of Camellia semiserrata Chi. The structures of these new flavonol glycosides were established as kaempferol 3-O-[(2'''''',3'''''',4''''''-triacetyl)-alpha-L-rhamnopyranosyl(1-->3)(2'''',4''''-diacetyl)-alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranoside] and kaempferol 3-O-[(3'''''',4''''''-diacetyl)-alpha-L-rhamnopyranosyl(1-->3)(2'''',4''''-diacetyl)-alpha-L-rhamnopyranosyl(1-->6)-beta-D-glucopyranoside] by spectroscopic methods. The estrogenic activity of these compounds was investigated by a recombinant yeast screening assay.