5a-Carba-a-D-mannopyranose

Controlled cA-dihydroxylation of the olefinic double bond of alcohol 141 allowed preparation of 5a-carba-a-D-glucopyranose (142), whilst 5a-carba-a-D-mannopyranose (146) and 5a-carba-P-D-glucopyranose (147) were prepared through epoxidation, ring opening, and final deprotection. Unfortunately, an attempt to obtain the P anomer of 146 by cis-... 

Gomez, A M, Danelon, G O, Moreno, E, Valverde, S, Lopez, J C, A novel entry to 5a-carba-hexopyranoses from carbohydrates based on a 6-exo-dig radical cyclization synthesis of 5a-carba-beta-D-mannopyranose pentaacetate, Chem. Commun., 175-176, 1999. 

Several 1,4-imino-linked carbadisaccharides containing 2-amino-2-deoxy-5a-carba-glucopyranosyl residues as analogues of the potent a-glucosidase inhibitor, acarviosine have been prepared, and the preparation of a manwo-configurated (1 ->6)-imino-linked unsaturated derivative using the reaction of methyl 6-amino-6-deoxy-a-D-mannopyranose with epoxide 112 has been reported. 

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