Conformation-Controlled Hydrogen-Bond-Mediated Aglycone Delivery Method for α-Xylosylation
Deqin Cai1,2, Ya Bian2,3, Shengjie Wu1,2
1University of Chinese Academy of Sciences, Beijing 100049, China.
Abstract:
α-Xylosylated glycans and xylosyl derivatives are biomedically important molecules which show numerous bioactivities against infection, cancer, inflammation, and so on. Lacking an efficient α-xylosylation method, the synthesis of α-xyloside-containing molecules was full of challenges. Herein, a robust method is presented for selective α-xylosylation via combination of a rare conformation-controlled strategy and the hydrogen-bond-mediated aglycone delivery method. Various native branched α-xyloside structures necessitate an orthogonally protected xyloside, and a three-pot preparation method of the xylosyl donor was developed for this novel α-xylosylation method, which was further applied in the first synthesis of the side chain N of xyloglucan. This work provides an efficient α-xylosylation method which would make various α-xyloside structures achievable. The conformation-controlled strategy also has important reference to the chemistry of five-carbon pyranose.
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