黄山药中甾体皂苷的分离与鉴定

目的　研究黄山药的化学成分，寻找新的活性物质。方法　用硅胶柱色谱及高效液相色谱等进行分离，通过理化方法及光谱分析(IR，ESI-MS，¹HNMR，¹³CNMR，DEPT，¹H-¹HCOSY，HMQC，HMBC，NOESY)鉴定化学结构。结果　从黄山药根茎的乙醇提取物中分离得到3种甾体皂苷，其化学结构分别鉴定为26-O-β-D-吡喃葡糖基-3β，26-二醇-23(S)-甲氧基-25(R)-Δ^5,20(22)-二烯-呋甾-3-O-［α-L-吡喃鼠李糖基-(1→2)-O-α-L-吡喃鼠李糖基-(1→4)］-β-D-吡喃葡糖苷(I)，伪原薯蓣皂苷(pseudoprotodioscin，II)，26-O-β-D-葡吡喃糖基25(R)-呋甾-Δ^5,20(22)-二烯-3β，26-二羟基-3-O-［α-L-鼠李吡喃糖基(1→2)］-β-D-葡吡喃糖苷(III)。结论　I为新化合物，命名为黄山药皂苷C，II，III为首次从本属植物中分得。

ISOLATION AND IDENTIFICATION OF STEROIDAL SAPONINS FROM DIOSCOREA PANTHAICA PRAIN ET BURKILL

AIM: To investigate the chemical constituents of the rhizomes of Dioscorea panthaica Prain et Burkill and look for new active compounds. METHODS: The compounds were isolated with silica gel and HPLC, and their structures were elucidated on the basis of chemical evidences and spectral analysis (IR, ESI-MS, 1HNMR, 13CNMR, DEPT, 1H-1H COSY, HMQC, HMBC, NOESY). RESULTS: Three steroidal saponins were isolated from the rhizomes of Dioscorea panthaica. They were elucidated as 26-O-beta-D-glucopyranosyl-3 beta, 26-diol-23(S)-methoxy-25(R)-delta 5,20(22)-diene-furosta-3-O-[alpha-L-rhamnopyranosyl-(1-->2)- O-alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (I), pseudoprotodioscin (II), 26-O-beta-D-glucopyranosyl-3 beta, 26-diol-25 (R)-delta 5,20(22)-diene-furosta-3-O-alpha-L-rhamnopyranosyl- (1-->2)-O-beta-D-glucopyranoside (III). CONCLUSION: Compound I is a new steroidal saponin and was named as dioscoreside C. Compound II and III were obtained from this genus for the first time.