Synthesis of apiose-containing oligosaccharide fragments of the plant cell wall: fragments of rhamnogalacturonan-II side chains A and B, and apiogalacturonan
作者:Sergey A. Nepogodiev、Margherita Fais、David L. Hughes、Robert A. Field
DOI:10.1039/c1ob05587a
日期:——
Fragments of pectic polysaccharides rhamnogalacturonan-II (RG-II) and apiogalacturonan were synthesised using p-tolylthio apiofuranoside derivatives as key building blocks. Apiofuranose thioglycosides can be conveniently prepared by cyclization of the corresponding dithioacetals possessing a 2,3-O-isopropylidene group, which is required for preservation of the correct (3R) configuration of the apiofuranose
果胶多糖rhamnogalacturonan-II (RG-II) 和apiogalacturonan 的片段是使用p- tolylthio apiofuranoside 衍生物作为关键构建块合成的。硫代呋喃糖苷可以通过相应的具有 2,3- O-异亚丙基的二硫代缩醛的环化来方便地制备,这是保持apiofuranose 环的正确 ( 3R ) 构型所必需的。这种保护基团在吡呋喃糖衍生物中的显着稳定性需要用更具反应性的保护基团替换,例如用于合成三糖 β-Rha p -(1→3')-β-Api f -的亚苄基缩醛- (1→2)-α-GalA p-OMe。该三糖的受保护前体的 X 射线晶体结构已被阐明。