Study On The Chemical Constitutions Of The Ethyl Acetate Exctract From Herpetospermum Pedunculosum

Herpetospermum pedunculosum（Ser.）C.B.Clarke（Cucurbitaceae）（synonym of Herpetospermum caudigerum Wall.ex Chakrav.）is a herbaceous medicinal plant which mainly distributed in southwest of China,Nepal and the northeast of India at about2300-3500 meters above sea level.Its dried ripe seed is a traditional Tibetan medicine for the treatment of liver diseases,cholic disorders,and dyspepsia.Early research on protective effects of ethyl acetate extract of H.pedunculosum againstα-naphthylisothiocyanate（ANIT）-induced acute cholestasis of rats of our research group.The results revealed that ethyl acetate extract have exhibited significant protective effect on ANIT-induced liver injury by reduce the increases in serum levels,restore the bile flow in cholestatic rats,and reduce the severity of the pathological tissue damage induced by ANIT.Based on the pharmacodynamics,the chemical components of H.pedunculosum were studied systematically and deeply.With the purpose of seeking for noval natural products and bioactive constituents,this research foucus on the in vitro constituents from the seed of H.pedunculosum.This article studied on the isolation and structure elucidation from the seed of H.pedunculosum,by extract with 95%alcohol,and fractionation with petroleum ether,ethyl acetate,saturated n-butanol extraction,successively.Fifty-two compounds were isolated by positive and reverse phase silica gel column chromatography,Sephedex LH-20 and semi-preparative HPLC.Their structures were identified by ¹H-NMR,¹³C-NMR,2D-NMR,UV,IR,CD,MS and X-ray.Detailed results as follows:7-en-nonadecanoic acid monoglyceride（MY-1）,dihydrocucurbitacin E（MY-2）,vomifoliol（MY-3）,threo-3,3’-dimethoxy-4,8’-oxyneoligna-9,4’,7’,9’-tetraol-7（8）-ene（MY-4）,hedyotol-A（MY-5）,（+）-menbrine（MY-6）,herpetolide D（MY-7）,（+）-pinoresinol（MY-8）,epipinoresinol（MY-9）,（-）-pinoresinol monomethyl ether（MY-10）,（1R,2R,5R,6S）-6-（4-hydroxy-3-methoxyphenyl）-3,7-dioxabicyclo[3.3.0]octan-2-ol（MY-11）,liballinol（MY-12）,herpetal（MY-13）,5-（3-hydroxy-2-（2-methoxyphenoxy）propanoyl）-2-（4-hydroxy-3-methoxyphenyl）-7-methoxybenzofuran-3-carbaldehyde（MY-14）,picrasmalignan A（MY-15）,saliglandol（MY-16）,（+）-isolariciresinol（MY-17）,burselignan（MY-18）,lariciresinol（MY-19）,asarinin A（MY-20）,（7S,8R）-threo-1’-[3’-hydroxy-7-（4-hydroxy-3-methoxyphenyl）-8-hydroxymethyl-7,8-dihydrobenzofuran]acrylaldehyde（MY-21）,balanophonin（MY-22）,dehydrodiconiferyl alcohol（MY-23）,herpetosiol G（MY-24）,herpetosin A（MY-25）,tetrahydro-2-（4-hydroxy-3-methoxyphenyl）-4-[（4-hydroxyphenyl）methyl]-3-furanmethanol（MY-26）,7’R*-methoxy-7-epi-lariciresinol（MY-27）,{（2S,3R,4R）-4-[1-ethoxy-1-（4-hydroxy-3-methoxy）phenyl]methyl-2-（4-hydroxy-3-me-thoxy）phenyl-3-hydroxymethyl-tetrahydrofuran}（MY-28）,tanegool（MY-29）,2,3-dihydro-2-（4-hydroxy-3-methoxyphenyl）-5-（3-hydroxy-1-propen-1-yl）-3-benzofuranmethanol（MY-30）,diospyrosin（MY-31）,cucurbitacin M（MY-32）,herpetone（MY-33）,herpetosiol H（MY-34）,herpetosiol I（MY-35）,pinnatifidanin B VIII（MY-36）,herpetosiol J（MY-37）,herpetosiol K（MY-38）,cinncassins D（MY-39）,erythro-guaiacylglycerol-β-O-4′-coniferyl ether（MY-40）,threo-guaiacylglycerol-β-O-4′-coniferyl ether（MY-41）,ehletianol C（MY-42）,herpetetrone（MY-43）,herpetosiol L（MY-44）,herpetosiol M（MY-45）,vanillic acid（MY-46）,（1S）-4-hydroxy-3-[2-（4-hydroxy-3-methoxy-phenyl）-1-hydroxymethyl-2-oxo-ethyl]-5-methoxy-benzaldehyde（MY-47）,（7R,7’R,7’’R,8S,8’S,8’’S）-4’,4’’-dihydroxy-3,3’,3’’,5-tetramethoxy-7,9’:7’,9-diepoxy-4,8’’-oxy-8,8’-sesqoineolignan-7’’,9’’-diol（MY-48）,spathulatol（MY-49）,phyllanglaucin B（MY-50）,herpetetradione（MY-51）,herpetosiol N（MY-52）.Among them,there were forty-five lignans including 13 ditetrahydrofuran,8 tetrahydrofuran,9 benzybutanes,10benzofuran,2 aryltetrahydronaphthalene and 3 others.Ten new compounds（MY-7,24,32,34,35,37,38,44,45,52）,one nor-cucurbitane triterpene with a novel skeleton（MY-25）and two new natural products（MY-14,30）were isolated from H.pedunculosum.Compounds MY-1,3,6,8-12,16,19,20,21,26-31,36,39,46,48,49,50 were isolated from this plant for the first.