Study Of The Chemical Composition Of Bitter Buckwheat

Fagopyrum tataricum (L.) Gaertn., also known as tartary buckwheat in Chinese, is one of the 15 species of Fagopyrum genus of Polygonaceae family. Various preparations of this plant are mainly used for the treatment of diabetes and hyperlipemia. Chemical constituents of this genus comprise flavonoids, phenolic acids, sterols, triterpenes and anthraquinone, etc. This paper describes the isolation and structure elucidation of the constituents from Fagopyrum tataricum (L.) Gaertn..Air-dried seeds of Fagopyrum tataricum were extracted with 95% EtOH three times. By means of solvent extraction, chromatography on silica gel and Sephadex LH-20 column, 16 compounds were isolated. NMR and MS were employed for structure identification, 14 of them were elucidated as:β-sitosterol (F-1), ursolic acid (F-2), daucosterol (F-3), kaempferol (F-4), quercetin (F-5), emodin (F-6), uracil (F-7), kaempferol-3-O-rutinoside (F-8), rutin (F-9), sucrose (F-10), protocatechuic acid (F-11), D-fructose (F-12), quercetin-3-O-rutinose-3'-O-glucoside (F-13), 7-hydroxycoumarin (F-14). Among them F-13 was a new compound, F-14 was isolated from Fagopyrum genus for the first time, F-2, F-10, F-11, F-12 were isolated from Fagopyrum tataricum for the first time.