Chemical constituents from Flos Sesamum indicum L.

Sesame (Sesamum indicum L.) belongs to Pedaliaceae, and its dry flowers have been used to cure alopecia, frostbite and constipation as a Traditional Chinese Medicine. Interestingly, the Flos Sesamum indicum L. was usually used to cure verruca vulgaris and verruca plana in folk of China, and showed a pleasant result. Previous chemical investigations of this plant mainly concentrate on its seeds, showed the presence of proteins and fat oils, herein we make a systematic chemical research on the dry flowers of this plant. Column chromatography including silica gel, C₁₈ and Sephadex LH-20 were used to separate the chemical constituents and the structures were determined by chemical and spectroscopic methods. Ten compounds were isolated from the 95% ethanol extract of the plant and elucidated as latifonin (1), momor-cerebroside (2), soya-cerebroside II (3), 1-O-β-D-glucopyranosyl-(2S,3S,4R,5E,9Z)-2-n-(2′-hydroxytetracosanoyl) 1,3,4-trihydroxy-5,9-octadienine (4), 1-O-β-D-glucopyranosyl-(2S,3S,4R,8Z)-2-N-(2′R) 2′-hydroxytetracosanoyl) 3,4-dihydroxy-8-octadene (5), (2S,1″S)-aurantiamide acetate (6), benzyl alcohol-O-(2′-O-β-D-xylopyranosyl, 3′-O-β-D-glucopyranoside)-β-D-glucopyranoside (7), β-sitosterol (8), daucosterol (9) and D-galacititol (10). Among them, 4 is a new compound, and others were isolated from the flowers of the plant for the first time. Compounds 2 to 4 belong to cerebroside, which is rare to be found in land plants and was proved to possess many bioactivities.