Stereoselective Synthesis of 1,1'-Disaccharides by Organoboron Catalysis
Sanae Izumi1, Yusuke Kobayashi1, Yoshiji Takemoto1
1Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Shimoadachi-cho, Yoshida, Sakyo-ku, Kyoto, 606-8501, Japan.
Abstract:
The highly stereoselective synthesis of 1,1'-disaccharides was achieved by using 1,2-dihydroxyglycosyl acceptors and glycosyl donors in the presence of a tricyclic borinic acid catalyst. In this reaction, the complexation of the diols and the catalyst is crucial for the activation of glycosyl donors, as well as for the 1,2-cis-configuration of the products. The anomeric stereochemistry of the glycosyl donor depends on the employed glycosyl donor. Applications of the produced 1,1'-disaccharides are also described.
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