Sugar silanes: versatile reagents for stereocontrolled glycosylation via intramolecular aglycone delivery
نویسندگان
چکیده
A new method for the intramolecular glycosylation of alcohols is described. Utilizing carbohydrate-derived silanes, the catalytic dehydrogenative silylation of alcohols is followed by intramolecular glycosylation. Appropriate combinations of silane position and protecting groups allow highly selective access to bmanno, a-gluco, or b-gluco stereochemical relationships as well as 2-azido-2-deoxy-b-glucoand 2deoxy-b-glucosides. Intramolecular aglycone delivery from the C-2 or C-6 position provides 1,2-cis or 1,2-trans glycosides, respectively. Multifunctional acceptor substrates such as hydroxyketones and diols are tolerated and are glycosylated in a site-selective manner.
منابع مشابه
Sugar silanes: versatile reagents for stereocontrolled glycosylation via intramolecular aglycone delivery† †Electronic supplementary information (ESI) available: Experimental details and copies of NMR spectra. See DOI: 10.1039/c5sc00810g
A new method for the intramolecular glycosylation of alcohols is described. Utilizing carbohydrate-derived silanes, the catalytic dehydrogenative silylation of alcohols is followed by intramolecular glycosylation. Appropriate combinations of silane position and protecting groups allow highly selective access to β-manno, α-gluco, or β-gluco stereochemical relationships as well as 2-azido-2-deoxy...
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