C7 Epimerization of Benzylidene-Protected β-<scp>d</scp>-Idopyranosides Brings Structural Insights into Idose Conformational Flexibility
作者:Maude Cloutier、Serge Lavoie、Charles Gauthier
DOI:10.1021/acs.joc.2c01504
日期:2022.10.7
high conformational flexibility in solution. We herein show that benzylidene acetal-protected 3-O-acyl-β-d-idopyranosides undergo Lewis acid-catalyzed C7 epimerization with concomitant 4C1 to 1C4 ring inversion. The reaction conditions and structural parameters for this transformation to occur have been thoroughly investigated through an extensive glycosylation study combined with NMR analyses, X-ray
Idose 在其他己醛糖中是独一无二的,因为它在溶液中具有高度的构象灵活性。我们在此表明亚苄基乙缩醛保护的 3- O-酰基-β- d-吡喃吡喃苷经历了路易斯酸催化的 C7 差向异构化,并伴随有4 C 1至1 C 4环反转。通过广泛的糖基化研究结合 NMR 分析、X 射线衍射和量子分子建模,已经彻底研究了发生这种转变的反应条件和结构参数。除了报告直接的 β-立体选择性 idosylation 方法外,我们的工作还为 idose 的构象灵活性带来了基本的结构见解。