Abstract

Six new triterpenes, uncarinic acids KP (1–6), along with 24 known analogues, were isolated as minor constituents of an aqueous decoction of the hook-bearing stems of Uncaria rhynchophylla (Gou-teng). By comprehensive spectroscopic data analysis, their structures were elucidated as derivatives of olean-12-en-28-oic acid and urs-12-en-28-oic acid with different oxidized forms at C-3, C-6, and/or C-23, respectively. Cell-based preliminary bioassay showed that the (E)-/(Z)-coumaroyloxy and (E)-/(Z)-feruloyloxy units at C-27 of olean-12-en-28-oic acid and urs-12-en-28-oic acid played roles in their bioactivities.

摘要

分离出六种新的三萜类，非carinic酸KP（1–6），以及24种已知的类似物，作为大叶钩藤钩钩茎水煎液的次要成分。通过全面的光谱数据分析，阐明了它们的结构为olean-12-en-28-oic酸和urs-12-en-28-oic酸的衍生物，它们在C-3，C-6和/或C-3处具有不同的氧化形式C-23。基于细胞的初步生物测定表明，olean-12-en-28-oic酸的C-27和urs-12-的（E）-/（Z）-香豆酰氧基和（E）-/（Z）-阿魏酰氧基单元en-28-oic acid在其生物活性中起作用。