Xin Meng, Wenlong Yao, Jiansong Cheng, Xu Zhang, Lan Jin, Hai Yu, Xi Chen, Fengshan Wang, and Hongzhi Cao
J. Am. Chem. Soc. 2014, 136, 5205−5208
A novel chemoenzymatic approach for the synthesis of disialyl tetrasaccharide epitopes found as the terminal oligosaccharides of GD1α, GT1aα, and GQ1bα is described. It relies on chemical manipulation of enzymatically generated trisaccharides as conformationally constrained acceptors for regioselective enzymatic α2−6-sialylation. This strategy provides a new route for easy access to disialyl tetrasaccharide epitopes and their derivatives.