茯苓硫酸酯化多糖的制备及其核磁共振波谱分析

目的]用不同方法制备3种茯苓多糖硫酸酯（Pachyman sulfate，PS），并对其进行核磁共振波谱对比分析，为多糖硫酸化提供基础数据。方法]以氯磺酸为磺化试剂硫酸化茯苓多糖制备茯苓多糖硫酸酯PS—I和PSII，以氨基磺酸为磺化试剂制备PS-Ⅲ，分析磺化反应前后和不同硫酸根取代度（Degree of sulfation，DS）的多糖碳原子化学位移的变化规律。结果]PS—I（DS=2．80）分子所有自由羟基均发生取代反应；PS—H（DS=1．55）C-6羟基被全部酯化，C-2和C-4羟基发生部分酯化反应；PS-Ⅲ（DS=0．95）C-6和C-2羟基发生部分硫酸酯化反应。结论]发生取代反应的碳原子化学位移移动的距离与PS的DS呈正相关，核磁共振技术能够提供多糖结构解析的关键数据。

Preparation and NMR Spectral Characterization of Pachyman Sulfate

Objective] Three kinds of Pachyman sulfate (PS) were synthesized with different methods, and were analyzed by Nuclear Magnetic Resonance (NMR), which will provide basic data for polysaccharide sulfation. Method] PS-Ⅰand PS-Ⅱwere prepared by using chlorosulfonic acid as sulfonic reagent at different reacting conditions, and PS-Ⅲ was prepared by using aminosulfonic acid as sulfonic reagent. The disciplinary varies of C-atom shifts of pachyman and PS with different DS (Degree of sulfation) were assayed. Result] All the hydroxyl groups of PS-I (DS = 2.80) molecule had been substituted by sulfate radical. The complete sulfation of the hydroxyl groups occurred at C-6, and the incomplete sulfation occurred at C-2 and C-4 of PS-Ⅱ(DS = 1.55) molecule. As for PS-Ⅲ (DS = 0.95) molecule, the incomplete sulfation of the hydroxyl groups occurred at C-6, C-2. Conclusion] The NMR spectra showed that the carbons shift intervals were proportional to the value of DS. NMR could offer the key data of resolving molecular structure of polysaccharides.