Merging Reagent Modulation and Remote Anchimeric Assistance for Glycosylation: Highly Stereoselective Synthesis of α‐Glycans up to a 30‐mer
作者:Yunqin Zhang、Haiqing He、Zixi Chen、Yingying Huang、Guisheng Xiang、Penghua Li、Xingkuan Yang、Gang Lu、Guozhi Xiao
DOI:10.1002/anie.202103826
日期:2021.5.25
and 6‐O‐levulinoyl remote anchimeric assistance glycosylation strategy, which is successfully applied to the first highly stereoselective synthesis of the branched Dendrobium Huoshanense glycans and the linear Longan glycans containing up to 30 contiguous 1,2‐cis glucosidic bonds. DFT calculations shed light on the origin of the much higher stereoselectivities of 1,2‐cis glucosylation with 6‐O‐levulinoyl
包含多个1,2-顺式糖苷键的长链,支链和复杂碳水化合物的有效合成是一项长期的挑战。在这里,我们报告了一种结合的试剂调节和6-O-乙酰丙酸远程嵌合辅助糖基化策略,该策略已成功地应用于分支石Hu霍山ense聚糖和线性龙眼聚糖的首次高度立体选择性合成,其中线性龙眼聚糖最多包含30个连续的1,2-顺式糖苷键。DFT计算揭示了6-O-乙酰丙酰基与1-O-乙酰基或6-O-苯甲酰基相比具有更高的1,2-顺式糖基化立体选择性的起源。在复杂聚糖的有效合成中,已经证明了基于糖基邻炔基苯甲酸酯和邻(1-苯基乙烯基)苯甲酸酯的正交单锅糖基化策略,