Study On The Chemical Constitutions Of The Ethyl Acetate Extract From Herpetospermum Caudigerum

Herpetospermum seed, a common folk medicine used by Tibetan medication, is the dried ripe seed of Herpetspermum Caudigerum Wall., It is distributed in Sichuan, Yunnan, Tibet of China and India. It grows in shrubs, forest margins and roadside. It is bitter in taste and cold in nature. It has effect for heat-clearing and detoxifying and is used to relieve jaundice, hepatitis caused by "chiba" diseases. The preliminary study illustrates the chemical constitutions mainly includes fatty acids, lignans, amino acids and polysaccharides. Further biological study show the ethyl acetate fraction has significant inhibitory activity against hepatitis B virus. The total lignans fraction and some compounds have protective effect against liver injury.and hepatitis. This paper studies on the extraction, isolation and identification of compounds from the ethyl acetate fraction, and the biological activity of some compounds, which provides a foundation for further biological experiment.The study crushing the dried seeds, then extracting the chemical composition b y 95% ethanol. Collecting eluate, evaporating solvent, the concentrated solution dispe rsed in water, then obtainning different fractions by extracting with petroleum ether, ethyl dceiaic and buianui. Removing the sugar and tat in the ethyl acetate extract pr oduce 237g extraction. Then using Silica gel column chromatography, Reverse-phase silica gel column chromatography, Sephadex chromatography, recrystallization and se mi-preparative column chromatography to separate and purificate until obtainning the monomer compound, the structure of compounds were identified by LC-MS,’H-NM R, 13C-NMR,2D-NMR. Finally, We identified 32 compounds, including 27 lignans, 3 triterpenoids,1 coumarin,1 flavonoid:Herpetfluorenone (1)、Herpetin (2)、Her petrione (3)、Herpetone (4)、Herpetetrone (5)、(+)-(7’S,7"S,8’R,8"R)-4,4’,4 "-trihydroxy-3,5’,3"-trimethoxy-7-oxo-8-ene [8-31,7’-O-9",8’-8",9’-O-7"] lignoid(6)、 Hedyotol A (7)、Dehydrodiconiferyl alcohol (8)、Herpetol(9)、Herpetotriol (1 0)、Picrasmalignan A (11)、Herpetal (12).. Balanophonin (13)、1-Propanone, 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-propen-1-yl)-2-methoxyphe noxy]-(14)、erythro-Guaiacylglycerol-(3-coniferyl ether (15)、threo-Guaiacylglyce rol-β-coniferyl ether (16)、 (7R,8S)-Dehydrodiconiferyl alcohol y’-methyl ether (17) 3-Benzofuranmethanol,2,3-dihydro-2-(4-hydroxy-3-methoxyphenyl)-7-methoxy-5-(3-meth oxy-1-propenyl)-, [2S-[2a,3b,5(E)]]-(9CI) (18)、Evofolin-B (19),1-Propanone,3-hydroxy-l-(2-hydroxy-5-methoxyphenyl)2-(4-hydroxy-3-methoxyphenyl)-(20)、Cue urbitacin R (21)-Cucurbitacin D (22), Cucurbitacin B (23)、Herpetolide A (2 4), Kaempferol 3,7-L-dirhamnoside (25)、Herpetatol A (26)、Herpetatol B (27)、 Herpetatol C (28), Herpetatol D (29)、Herpetatol E (30)、Herpetatol F (31)、 Herpetatol G(32). Compound 26-32 are new compounds, named Herpetatol A-G, Among the other compounds, compound 7、11、13、15～22、25 were isolated from this plant for the first time.Studying on the biological activity of some compounds shows compound 2,3 have a inhibiting effect against Candida albicans ATCC 14053, their MIC value are 10.5μM and 9.2μM. Meanwhile, the cytotoxic activity experiment illustrates compound 22 has a significant inhibitory effect, but further study show the inhibition ratio of this compound is lower than doxorubicin(positive control).