Synthesis of Sulfated Glycans

Abstract

Sulfated glycans are involved in numerous physiological and developmental functions that occur mainly as a result of their interactions with basic residues of binding proteins. Several of these sugars are polysulfated polysaccharides that possess structural microheterogeneity, particularly in their sulfation patterns. Understanding the structural features that influence the binding event and the eventual function is the goal of structure–activity relationship evaluations, which require sugar molecules of defined structures. Because the nature-sourced materials are inherently heterogeneous, these important compounds are mainly accessed through chemical and chemoenzymatic synthesis. The synthetic protocols are confounded by the introduction of sulfonate moieties at specific locations within the sugar chain. To accomplish this task, sophisticated protecting group combinations and a systematic application of enzymatic reactions are applied for the respective techniques. New sulfonation methods that improve the yields and reduce the cost were also developed over the years. A summary of the protocols applied to sulfated glycans with particular focus on sulfonation is provided herein.