Glucopyranoside methyl 6-deoxy-6-fluoro

Cyclic sulfates rapidly react with the fluoride ion sources to give monofluoro derivatives Thus, the 2,3-cyclic sulfate of methyl-4 6 O benzylidene p D manno pyranoside cleanly reacts with tetramethylammonium fluoride to give methyl 4,6-0-benzylidene 2 deoxy 2 fluoro-p-D-glucopyranoside-3-sulfate Acid hydrolysis followed by acetylation gives 2 deoxy 2 fluoro-P-D-glucopyranoside triacetate in 84% isolated yield [5S] (equation 38)... 

A mixture of methyl 3-deoxy-3-C-methyl-3-nitro-ct-D- and fi-L-glucopyranosides d l is formed by the reaction of nitroethane with the sugar thaldehyde obtained from L-glucose The products are separated and converted into branched-chain fluoro nitro l- and L-sugars fEq 361 ... 

Potassium fluoride in 1,2-ethanediol has further been used, as, for example, in the preparation of 5-deoxy-5-fluoro-D-ribose from methyl 2,3-0-isopropylidene-5-0-(methylsulfonyl)-a-D-ribofuranoside,87 and of 6-deoxy-6-fluoro-D-glucose from methyl 6-O-p-tolylsulfoiiyl-a-D-glucopyranoside.77 In one study of primary fluorinations with potas-... 

The 3-0-benzyl derivative underwent a rapid reaction with TASF at reflux temperature to give methyl 3-0-benzyl-A,6-0-benzylidene-2-deoxy-2-fluoro-p- -glucopyranoside (J ) in A5% yield, and a minor product (19% yield) tentatively assigned the structure of methyl 3-0-benzvl-A.6-0-benzvlldene-2-deoxv-B-D-ervthro-hex-2-enopyranoslde. Base-catalyzed elimination reactions with trlflyl derivatives are uncommon (, ), but have been observed In certain furanoid (A0,A2) and, recently, in pyranoid (33,35) ring systems (see also Table I). Eliminations in glycopyranosldes occurred (33,35) under conditions which decreased the ease of nucleophilic substitution (33,A3,AA). 

P. G. Hultin and R. M. Buffie, Syntheses of methyl (4,6-dideoxy-a-L-/yxo-hexopyranosyl)-(l ->3)-and (4-deoxy-4-fluoro-a-L-rhamnopyranosyl)-(l ->3)-2-acetamido-2-deoxy-a-D-glucopyranosides, analogs of the mycobacterial arabinogalactan linkage disaccharide, Carbohydr. Res., 322 (1999) 14-25. 

MXFGPY. Methyl 4-deoxy-4-fluoro-a-D-glucopyranoside (C7H13F05). Choong W, Stephenson NC, Stevens JD (1975) Cryst Struct Commun 4 491 MXLPYR. Methyl a-D-xylopyranoside (C6H1205). Thkagi S, Jeffrey GA (1978) Acta Crystallogr, Sect B 34 3104... 

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