A new flavonolignan from milk thistle ( Silybum marianum ).

A new flavonolignan, sonyamandin (1) , along with other known compounds was isolated from the aerial parts and seeds extracts of Silybum marianum (milk thistle) collected from Jordan. The known ones are ursolic acid (2) , oleanolic acid (3) , maslinic acid (4), oleic acid (5) , β-sitosterol (6) , β-, sitosteryl glucoside (7), apigenin (8) , kaempferol-3-O-rhamnoside (9) , apigenin-7-O-β-D-glycoside (10) , isosylibin A (11) , isosylibin B (12), and silybin B (13) . The absolute stereochemistry of 1 was confirmed by 2D NMR and CD analysis.