O-Glycosylation Enabled by Remote Activation

Abstract

O-Glycosylation is a critically important and recurring step in the synthesis of oligosaccharides and other natural and non-natural products. While many approaches to O-glycosylation have been reported, those strategies involving remote activation are distinguished by the mildness and orthogonality that they often engender. As a result, O-glycosylation using remote activation strategies has been utilized successfully in the synthesis of complex molecules that include oligosaccharides and macrolides. Herein, we discuss a number of contributions that have been made to this area since the 1970s. This includes our own recent contribution involving the visible-light activation of 4-<i>p</i>-methoxyphenyl-3-butenylthioglycosides toward O-glycosylation in the presence of Umemoto’s reagent. 1 Introduction 2 Fraser-Reid’s Development of n-Pentenylglycosides as Glycosyl Donors 3 Hanessian’s Remote Activation of 2-Pyridylthioglycosides 4 Gold-Catalyzed O-Glycosylation (Hotha and Yu) 5 Wan’s ‘Interrupted Pummerer’ Approach to O-Glycosylation 6 O-Glycosylation with 4-<i>p</i>-Methoxyphenyl-3-butenylthioglycosides 7 Conclusions