关键词: 紫外分光光度法, 化学成分, 红外分光光度法, 皂角苷, 质谱法, 核磁共振谱法, 碳13核磁共振谱法, 吡喃糖, 葡萄糖, 毛冬青

A new saponin, named ilexsaponin A (I), was isolated from the roots of I. pubescens and its structure elucidation is reported. I, white needles, C36H56O11, m.p. 285-287?(decompn.), [a]D11 + 39.2? who has pos. to the Liebermann-Burchard test. By hydrolysis with 5% H2SO4-EtOH, I afforded glucose and saponin (II), C30H46O5, which was converted to several derivatives When I was hydrolyzed with 2% HCl-MeOH, 3 artifact sapogenins were formed, which were also converted to several derivatives The structure of I was shown to be 3b,19a-dihydroxy-urs-12-ene-24,28-dioic acid-28-b-D-glycopyranosyl ester by the above chem. conversions and spectral anal. of 13C NMR, 1H NMR, MS, IR and UV. II is a new 19a-hydroxyursane sapogenin.

Key words: ULTRAVIOLET SPECTROPHOTOMETRY, CHEMICAL COMPOSITION, INFRARED SPECTROPHOTOMETRY, SAPONINS, MASS SPECTROGRAPHY, NMR SPECTROMETRY, C13 NMR SPECTROMETRY, PYRANOSE, GLUCOSE, ILEX PUBESCENS