三尖杉碱骨架构筑中间体末端炔键的NMR确证  

Characterization of the Terminal Alkyne Group in a Key Intermediate of Cephalotaxine by NMR Spectroscopy

作　　者：雷连娣[1] 刘雪辉[1] 金赟[2] 姜标[2] 崔育新[1] 

机构地区：[1]北京大学医药卫生分析中心,北京100083 [2]中国科学院上海有机化学研究所,上海200032

出　　处：《波谱学杂志》2008年第1期46-52,共7页Chinese Journal of Magnetic Resonance

摘　　要：3-(6-乙炔基-苯并[1,3]二氧杂环戊烯-5-基)-2-羟基-丙磺酸-4′-碘-4′-戊烯酯是我们设计的三尖杉碱化合物合成路线中的关键中间体,其分子中的末端炔键对于构建三尖杉碱的环状结构及立体化学至关重要.常规DEPT和HSQC实验中均不能得到末端炔键存在的信息,导致合成步骤无法继续进行.本文通过研究异核一键耦合常数设置值对DEPT实验和HSQC实验的影响,为关键中间体3-(6-乙炔基-苯并[1,3]二氧杂环戊烯-5-基)-2-羟基-丙磺酸-4′-碘-4′-戊烯酯末端炔键的确定给出了确切的信息,准确指定了化合物的结构,对分子中含有末端炔键化合物的NMR研究提供了数据参考和实验方法.3- （6-Ethynyl-benzo[1,3] dioxol-5-yl） -2-hydroxy-propane- 1-sulfonic acid 4-io- do-pent-4-enyl ester is a key intermediate in the synthesis of cephalotaxine. The terminal alkyne group in the compound is known to play important roles in constructing the three-ring structure and in establishing stereochemistry of cephalotaxine. It is necessary to confirm the existence of such terminal alkyne group in the intermediate before the next synthetic step being performed. However, normal DEPT and HSQC spectra ac- quired with the assumption ^1JCH=140 Hz could not provide any information about the terminal alkyne group. To solve this problem, the experimental parameters for acquiring DEPT and HSQC spectra were tuned carefully, allowing ^1JCH to vary in a range. The existence of the alkyne group in the intermediate compound was successfully demonstrated. A complete assignment of the ^1H and ^13C chemical shifts of the compound was also reported. The method presented in this paper is potentially useful for studies of analogous compounds.

关 键 词：NMR 末端炔键 ^13C-^1 H异核耦合常数 三尖杉碱 

分 类 号：O641[理学—物理化学]