Three new pterosins from Pteris semipinnata.

Three new pterosins, named as semipterosin A (1), B (2) and C (3), together with 11 known pterosins (4-14), were isolated from the aerial parts of Pteris semipinnata. Their structures were elucidated by HRESI-MS, NMR spectral data, CD and literature comparisons. Three new pterosins were assessed for their anti-inflammatory activity. Compounds 1-3 inhibited the NF-kB induction by 40.7%, 61.9% and 34.0%, respectively. This is the first report of the isolation of compounds 6-14 from this plant.

Three new flavonoid glycosides isolated from Pteridium aquilinum.

Three new flavonoid glycosides, (S)-4',6,8-trihydroxyflavanone-7-C-glucoside (1), (R)-4',6,8- trihydroxyflavanone-7-C-glucoside (2) and distenin-7-O-ß-D-glucoside (3), along with nine known flavonoids (4-12) were isolated from the aerial of Pteridium acquilinum. Their structures were elucidated by the analysis of spectroscopy data and their comparison with the reported values. The two C-glycosyl flavanones (1 and 2), were isolated from this specie, which might be chemotaxonomic markers of this specie. In addition, three new flavonoids were preliminarily examined for their anti-inflammatory activity. Compounds 1-3 inhibited the NF-κB induction by 46.3%, 59.6% and 29.2%, respectively.