穿龙薯蓣总皂苷中甾体皂苷的分离与鉴定

ISOLATION AND IDENTIFICATION OF STEROIDAL SAPONINS IN TOTAL SAPONIN FROM DIOSCOREA NIPPONICA MAKINO

目的 研究穿龙薯蓣总皂苷中水溶性甾体皂苷 ,寻找新的生物活性化合物。方法 用硅胶柱色谱、薄层色谱及高效液相色谱等进行分离 ,通过酸水解、理化常数和波谱学分析 (IR ,NMR ,MS ,HMQC ,HMBC)鉴定化合物结构。结果 从穿龙薯蓣总皂苷中分得 2个甾体皂苷 ( 1个水难溶性皂苷和 1个水溶性皂苷 ) ,其化学结构分别鉴定为薯蓣皂苷元 3 O {α L 鼠李糖 ( 1→ 2 ) [β D 葡萄糖 ( 1→ 3 ) ]} β D 葡糖皂苷 (I) ,薯蓣皂苷元 3 O [α L 鼠李糖 ( 1→ 3 ) α L 鼠李糖 ( 1→ 4 ) α L 鼠李糖 ( 1→ 4 ) ] β D 葡糖皂苷 (II)。 结论 II为首次从穿龙薯蓣中分离得到的新化合物 ,命名为穿龙薯蓣皂苷Dc。

AIM To investigate the water soluble steroidal saponins in total saponin from Dioscorea nipponica Makino and look for new active compounds. METHODS The compounds were isolated with silica gel, PTLC and HPLC, and their structures were elucidated by acid hydrolysis, physical and chemical data and spectral analysis (IR, NMR, MS, HMQC, HMBC) as well as chemical correlations. RESULTS The two steroidal saponins (water insoluble saponin and water soluble saponin) were isolated from the total saponin of Dioscorea nipponica Makino. The structures were elucidated as diosgenin 3 O {α L rhamnopy ranosyl (1→2) [β D glucopyranosyl (1→3)]} β D glucopyranoside (I), diosgenin 3 O [α L rhamnopyranosyl (1→3) α L rhamnopyranosyl (1→4) α L rhamnopyranosyl (1→4)] β D glucopyranoside (II). CONCLUSION Compound II is a new steroidal saponin and firstly isolated from Dioscorea nipponica Makino. It was named as dioscin Dc.