Ma Xiaoxia, Yang Chongren, Zhang Yingjun
State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, P. R. China.
Magn Reson Chem. 2008 Jun;46(6):571-5. doi: 10.1002/mrc.2212.
The complete assignments of all the (1)H and (13)C NMR signals of three polyhydroxylated 12-ursen-type triterpenes, 6beta,19alpha,22alpha-trihydroxyurs-12-en-3-oxo-28-oic acid (1), 3beta,6alpha,19alpha,23-tetrahydroxyurs-12-en-28- oic acid (2) and 3beta,6beta,19alpha,23-tetrahydroxyurs-12-en-28-oic acid (3), were carried out by means of homo- and hetero-nuclear two-dimensional NMR experiments. Compounds 1-3 were isolated from the aerial parts of Dischidia esquirolii. Of them, 1 and 2 were identified as new polyhydroxylated ursolic acid derivatives. Compound 2 is the C-6 hydroxyl epimer of 3, which was isolated first from Adina rubella, and its structure is revised in this paper.
通过同核和异核二维核磁共振实验，对三种多羟基化12-乌苏烷型三萜化合物，即6β,19α,22α-三羟基乌苏-12-烯-3-氧代-28-酸（1）、3β,6α,19α,23-四羟基乌苏-12-烯-28-酸（2）和3β,6β,19α,23-四羟基乌苏-12-烯-28-酸（3）的所有¹H和¹³C NMR信号进行了完整归属。化合物1 - 3是从贵州瓜子金的地上部分分离得到的。其中，1和2被鉴定为新的多羟基化熊果酸衍生物。化合物2是3的C-6羟基差向异构体，3最初是从水团花中分离得到的，本文对其结构进行了修正。
