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Stereocontrolled Synthesis of α-Xylofuranosides Using a Conformationally Restricted Donor.

ABSTRACT: A number of biologically relevant glycoconjugates possess 1,2- cis-furanosidic linkages, a class of glycosidic bond that remains challenging to introduce with high stereoselectivity. In this paper, we report an approach to one family of such linkages, α-xylofuranosides, via the use of thioglycoside donors possessing a conformationally restricting xylylene protecting group. The method was shown to provide the desired targets in good to excellent yield and stereoselectivity. Computational investigations support the proposal that the protecting group locks the electrophilic intermediate in these reactions into a conformation that leads to the high selectivity. The power of the methodology was demonstrated through the synthesis of a complex hexasaccharide motif from lipoarabinomannan, an immunomodulatory polysaccharide from mycobacteria.

SUBMITTER: Zhang L

PROVIDER: S-EPMC6079929 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Stereocontrolled Synthesis of α-Xylofuranosides Using a Conformationally Restricted Donor.

Zhang Li L Shen Ke K Taha Hashem A HA Lowary Todd L TL

The Journal of organic chemistry 20180626 15

A number of biologically relevant glycoconjugates possess 1,2- cis-furanosidic linkages, a class of glycosidic bond that remains challenging to introduce with high stereoselectivity. In this paper, we report an approach to one family of such linkages, α-xylofuranosides, via the use of thioglycoside donors possessing a conformationally restricting xylylene protecting group. The method was shown to provide the desired targets in good to excellent yield and stereoselectivity. Computational investig ...[more]

PMID: 29895148

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