2- Deoxy-2-fluoro-p-D-glucopyranosid

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)... 

The reaction of benzyl 3,Ajh-tri-O-benzyl-Z-O-trifluoromethane-sulfonyl-p-D-mannopyranoside ( ) with TASF was complete in less than 5 min below room temperature, to give a low (11%) yield of benzyl 3,A,5-tri-0-benzyl-2-deoxy-2-fluoro-p-D-glucopyranoside (15), whereas the isomeric a-D-mannopyranoside reacted relatively slowly with TASF at room temperature to give a product tentatively assigned the structure of 17. 

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). 

Benzyl 3-deoxy-3-fluoro-p-D-glucopyranoside, D-89 Benzyl 5-deoxy-3-C-(hydroxymethyl)-a-L-lyxofuranoside, D-230 Benzyl 3-deoxy-3-iodo-p-L-xylopyranoside, D-280 Benzyl l-deoxy-4,5-0-isopropylidene-D-erji/irO hexo-2,3-diulo-3,6-furanoside, D-186... 

Methyl 2-0-acetyl-4,6-0-benzylidene-3-deoxy-3-fluoro-p-D-glucopyranoside, D-89... 

Fig. 2.2.S.4 Sucrose analogues synthesized with recombinant SuSyl from yeast. 23 I -deoxy-l -fluoro-P-D-fructofuranosyl-a-D-glucopyranoside 24 [ C,]-ji-D-fructofuranosyl-a-D-glucopyranoside 25 a-D-glucopyranosyl-a-L-sorbofuranoside 26 a-D-glucopyranosyl-a-D-lyxopyranoside 27 2-acetamido-2-deoxy-a-D-glucopyranosyl-P-D-fructofuranoside.

Me glycoside, N,0,0-fr - c Methyl 2-acetamido-3,6-di-0-acetyl-2,4-di-deoxy-d-fluoro-p-D-glucopyranoside C13H20FNO7 321.302 Rods (Et0Ac/Et20). Mp 174-176°. [a]o -61.4 (c, 1 in MeOH). 

Methyl 3,5-di-0-benzoyl-2-bromo-2-deoxy-a-D-ribofuranoside, B-92 Methyl 2,3-di-0-benzoyl-5-bromo-5-deoxy-p-D-ribofuranoside, B-93 Methyl 2,5-di-0-benzoyl-3-bromo-3-deoxy-a-D-xylofuranoside, B-103 Methyl 2,5-di-0-benzoyl-3-bromo-3-deoxy-p-D-xylofuranoside, B-103 Methyl 2,3-di-0-benzoyl-4-bromo-4-deoxy-a-L-xylopyranoside, B-104 Methyl 2,3-di-0-benzoyl-6-chloro-6-deoxy-a-D-glucopyranoside, C-88 Methyl 3,4-di-0-benzoyl-2-deoxy-2-fluoro-D-ribofuranoside, D-106 Methyl 3,4-di-0-benzoyl-2-deoxy-2-fluoro-i>ribopyranoside, D-106 Methyl 3,6-di-0-benzoyl-2-deoxy-a-D-g/Fcero-hex-2-enopyranosid-4-ulose, D-178... 

Methyl 3-acetamido-3-deoxy-p-D-glucopyranoside, A-267 Methyl 2-acetamido-2-deoxy-5-thio-a-D-glucopyranoside, A-349 Methyl 2-acetamido-3,6-di-0 -acetyl-2,4-dideoxy-4-fluoro-a-D-glucopyranoside, A-373... 

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-... 

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. 

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