Chemical constituents in heartwood of Taxus yunnanensis / 中草药

ABSTRACT

Objective To intensively investigate the chemical constituents in the heartwood of Taxus yunnanensis Cheng et L.K.Fu.Methods The heartwood was extracted with ethanol,the ethanol extract was subjected to the extraction with methylene trichloride,which was submitted to chromatography on sili-ca gel and Sephadex LH-20 column to isolate some compounds.And their structures were elucidated on the basis of spectral analysis(UV,IR,ESI-MS,1H-NMR,13C-NMR).Results The compounds were identified as 2?,5?,7?,9?,10?,13?-hexaacetoxy-4(20),11-taxadiene(Ⅰ),taxusin(Ⅱ),taxa-4(20),11-diene-2?,5?,10?-triacetoxy-14?,2-methybutyrate(Ⅲ),10?-hydroxy-2?,5?,14?-triacetoxy-4(20),11-taxadiene(Ⅳ),1-dehydroxybaccatin Ⅳ(Ⅴ),baccatin Ⅳ(Ⅵ),baccatin Ⅵ(Ⅶ),7,9-deacetylbaccatin Ⅵ(Ⅷ),10-deacetyltaxuyannine(Ⅸ),1?-accetoxy-5-deacetyl-baccatin Ⅰ(Ⅹ),baccatin Ⅰ(Ⅺ),taxuchin A(Ⅹ Ⅱ),secoisolariciresinol(Ⅹ Ⅲ),?-conidendrin(Ⅹ Ⅳ),isotaxiresinol(Ⅹ Ⅴ),lariciresinol(Ⅹ Ⅵ),sequoitol(Ⅹ Ⅶ),?-sitosterol(Ⅹ Ⅷ).Among them compounds Ⅰ,Ⅴ,Ⅵ,Ⅺ,Ⅹ Ⅱ,Ⅹ Ⅵ were obtained from the heartwood of T.yunnanensis for the first time.Conclusion The chemical constituents in the heartwood differ from the other parts of T.yunnanensis,but there is little difference within the species of Taxus L.