Phytochemical and biological studies of Carduus pycnocephalus L.

Seven flavonoidal compounds, apigenin (1), kaempferol-3-O-β-d-glucoside (2), kaempferol-3-O-α-l-rhamnoside (3), kaempferol-7-methoxy-3-O-α-l-rhamnoside (4), diosmetin-7-O-β-d-xylosyl-(1‴→6″)-β-d-glucopyranoside (5), diosmetin-7-O-α-l-arabinosyl (1‴→6″)-β-d-glucopyranoside (6), kaempferol-3-O-α-l-rhamnosyl-(1‴→2″)-α-l-rhamnoside (7), in addition to lupeol (8), β-sitosterol (9) and β-sitosterol-3-O-β-d-glucoside (10) were isolated from the aerial parts of Carduus pycnocephalus L. The structures of the isolated compounds were established by UV, IR, FAB-MS, ESI-MS, EI-MS, 1D and 2D NMR spectroscopic methods. Compounds 1, 2, and 4 were reported for the first time from C. pycnocephalus and compounds 5 and 7 were first reported from the genus Carduus. Anti-inflammatory, antispasmodic and hypotensive activities were assessed for all extracts which showed variable activities.