盾叶薯蓣鲜根茎中甾体皂苷的分离鉴定

Isolation and identification of steroidal saponins from fresh rhizome of Dioscorea zingiberensis

目的研究盾叶薯蓣Dioscorea zingiberensis鲜根茎中的甾体皂苷成分,寻找新的生物活性物质。方法运用正相和反相C_(18)硅胶柱色谱对其甾体皂苷成分进行分离,用IR、MS、NMR等光谱方法进行结构鉴定。结果从乙醇提取物中分离鉴定了3个甾体化合物,分别为纤细皂苷(gracillin.Ⅰ)、盾叶皂苷A(zingiberenin A.Ⅱ)和26-O-β- D一吡喃葡萄糖基-3β,26-二醇-25(R)-呋甾烷-5,20(22)-双烯-3-O-{α-L-吡喃鼠李糖基-(1→4)-[β-D-吡喃葡萄糖基一(1→3)-β-D-吡喃葡萄糖基-(1→2)]}-β-D-吡喃葡萄糖苷(26-O-β-D-glucopyranosyl-3β,26-diol-25(R)-furosta-5,20(22)-dien-3-O-{a-L-rhamnopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl-(1→2)]}-β-D- glucopyranoside,Ⅲ)。结论化合物Ⅲ为一新化合物,命名为盾叶皂苷G(zingiberenin G)。

Objective To study the steroidal saponins from the fresh rhizome of Dioscorea zingiberensis and search for new bioactive compounds. Methods The steroidal saponins were isolated by normal phase silica gel and RP-C18 column chromatography. Their chemical structures were elucidated by IR, MS, and NMR methods. Results Three steroidal saponins were isolated from-EtOH extract of the fresh rhizome of D. zingiberensis and identified as gracillin （Ⅰ）, zingiberenin A （Ⅱ）, and 26-O-β-D-glucopyranosyl-3β, 26-diol- 25 （R）-furosta- 5, 20（22）-dien-3-O-{α-L-rhamnopyranosyl- （ 1→4 ）- [β-D-glucopyranosyl- （ 1→3 ）-β- D-glucopyranosyl-（1→2）]}-β-D-glucopyranoside, Ⅲ）. Conclusion Compound Ⅲ is a new compound named as zingiberenin G.