Two new triglycosides of oleanane-type triterpenes, rotundioside E (3) and F (1), isolated from the leaves of Bupleurum rotundifolium L. were identified as 16α, 28-dihydroxyoleana-11, 13 (18)-dien-3β-yl α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→2)-β-D-fucopyranoside (3) and 13β, 28-epoxy-16α-hydroxyoleana-11-en-3β-yl α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl-(1→2)-β-D-fucopyranoside (1), respectively, on the basis of chemical and spectroscopic evidence.
of CrO3, pyridine, and BunOH saturated with water. The reaction of the oleananetriterpenoid glycosides (1), (4), and (5) with reagent A gave 11-oxo-compounds (3) and (6), which indicated that this reagent is useful for the oxidation of an allyl alcohol and an allyl ether. On the other hand, the reaction of oleananetriterpenoids (11), (13), (14), and (15) with reagent A gave 16-oxo-derivatives (9)
从CrO 3,吡啶和用水饱和的Bu n OH的混合物中获得试剂A(确切的组成未知)。齐墩果烷三萜糖苷(1),(4)和(5)与试剂A的反应生成11-氧代化合物(3)和(6),这表明该试剂可用于烯丙醇的氧化和烯丙基醚 另一方面,齐墩果烷三萜类化合物(11),(13),(14)和(15)与试剂A的反应产生了16-氧代衍生物(9),(16),(17)和(18)。 ,同时化合物(19)和(22)与该试剂一起生成21-氧代衍生物(24)和(25)。试剂A对于16和21轴羟基的选择性氧化也非常有用。