Exploring the Far Side of Glycosyl Sulfoxide Activation Process

Abstract

The discovery of Kahne glycosylation forwards a big step in the carbohydrate chemistry. Despite an extensive series of studies, the precise mechanism of this powerful glycosylation is still not fully understood. To address these 30-year puzzles, the far side of Kahne glycosylation is explored in this study. After a series of control and tracking experiments, a number of important intermediates including glycosyl oxo-sulfonium ion and sulfenic anhydride (Crich's intermediate) are suggested to be responsible for the complex reaction pathway. It also reveals that in addition to the conventional ionic glycosylation pathway, a novel free radical pathway is very likely to contribute to the various side-and co-products. This study provides further understanding of Kahne glycosylation, and it also sheds light on how to improve the efficiency of sulfoxide-based glycosylation reactions.

Recent Advances in Glycopeptide and Glycoprotein Synthesis: A Refined Synthetic Probe towards the Biological World

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Enzymatic Synthesis of Sialyl Lactosamine Grafted Chitooligosaccharides

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