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Updated: Jan 17, 2026

Metabolic Glycoengineering of Sialic Acid Using N-acyl-modified Mannosamines
Published on: November 25, 2017
Investigation of the Reactivities of Halogen-Substituted Bicyclic Sialic Acid Donors and Their Application
Maina Takahashi1, Sakuma Yasutake2, Sung-Chi Lin3
1Institute for Glyco-core Research (iGCORE), Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
Abstract:
We previously developed a fully stereoselective α-sialylation using a macrobicyclic donor. We report that dihalogen substitutions on the macrocyclic moiety greatly enhance the reactivity of macrobicyclic donors. Furthermore, by using Cl- and F-substituted donors, we achieved late-stage regioselective C5 modifications of α(2,8)-linked disialic acids─highly challenging synthetic targets of significant biological importance. This study broadens the utility of the fully stereoselective α-sialylation and underscores the importance of amino group modifications in glycosylation.
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