Chemoenzymatic iterative synthesis of difficult linkages of oligosaccharides on soluble polymeric supports

Abstract

Equation presented A trisaccharide donor containing a cis-Galpα(1→4)Galp linkage was prepared using a synthetic strategy based on chemoenzymatic oligosaccharide synthesis on a soluble polymeric support. Significantly, only retaining glycosyltransferases gave complete reactions, whereas inverting enzymes showed little or no activity with poly(ethylene glycol) (MPEG)-bound lactose as an acceptor. The MPEG-attached trisaccharide was shown to bind to Verotoxin-1 by transfer NOE studies through the Galpα(1→4)Galp portion of the molecule.