6-Deoxy-a-D-galactopyranose

Tetra-Ac 1,2,3,4-Tetra-0-acetyl-6-azido-6-deoxy-a-D-galactopyranose [73108-24-4]... 

RX. n-butyl bromide n-dodecanyl iodide cyclohexyl iodide ethyl bromo acetate methyl 2,3-di-O-acetyl-4-O-benzoyl-6-bromo-6-deoxy-ot-D-glucopyranoside methyl 2,3,4-tri-0-acetyl-6-deoxy-6-iodo-0 -D glucopyranoside l,2 3,4-di-0-isopropylidene-6-deoxy-6-iodo-a-D-galactopyranose methyl 2(R)-[(tert-butoxycarbonyl)amino]-3-iodo-propionate cyclic bis(trifluoromethyl)oxazolidinone bromide. 

Penta-Ac 2-Acetamido-l,3,4,6-tetra-O-acetyl-2-deoxy-a-D-galactopyranose [10385-50-9]... 

Tetra-Ac 1,3,4,6-Tetra-0-acetyl-2-azido-2-deoxy-a-D-galactopyranose [67817-30-5]... 

Acetamido-l,2,3,5-tetra-0-acetyl-4-deoxy-p-D-arabinofnranose, A-179 2-Acetamido-l,3,4,6-tetra-0-acetyl-2-deoxy-a-D-galactopyranose, A-206 2-Acetamido-l,3,4,6-tetra-0-acetyl-2-deoxy-p-D-galactopyranose, A-206 4-Acetamido-l,2,3,6-tetra-0-acetyl-4-deoxy-a-D-glucopyranose, A-268... 

Deoxy-6-fluoro-a-D-galactopyranose l-(dihydrogen phosphate), D-83 6-Deoxy-6-fluorogalactose a-D-Pyranose-/orm, D-83 6-Deoxy-6-fluoro-a-D-glucopyranosyl fluoride, 8CI, D-92 6-Deoxy-6-fluoro-p-D-glucopyranosyl fluoride, 8CI, D-92 6-Deoxy-6-fluoro ucose i>-form, I>92 6-Deoxy-6-fluoro-l,2-0-isopropylidene-a-D-glucofuranose, D-92 6-Deoxy-6-fluoro-2,3-0 -isopropylidene-1 -O -tosyl-p-D-fructofuranose, D-76... 

Difluoro compounds have been prepared by treatment of carbonyl compounds with DAST. These are methyl 5-deoxy-5,5-difluoro-2,3,-0-isopropylidene-)S-D-ribofuranoside, 6-deoxy-6,6-difluoro-1,2 3,4-di-0-isopropylidene-a-D-galactopyranose, methyl 2-deoxy-2,2-difluoro-... 

Deoxy-3-[ F]fluoro-D-glucose ( F-3DFG) was prepared - 454,467,473-476 essentially according to the procedure for the cold synthesis (see Section 11,2), namely, treatment of248 with Cs F (in DMF or HMPA), tetraalkylammonium [ F]fluoride (DMF, HMPA, or MeCN) or K F (in acetamide). 6-Deoxy-6-[ F]fluoro-a-D-galactopyranose was likewise pre-pared aceording to the cold synthesis. ... 

The Arbuzov reaction has been applied for the synthesis of fluorinated carbohydrates. 1,2 3,4-Di-O-isopropylidene-a-D-galactopyran-ose 6-(N,N-diethyl-P-methylphosphonamidite) was treated with ethyl fluoroacetate, to afford 6-deoxy-6-fluoro-l,2 3,4-di-O-isopropylidene-a-D-galactopyranose in 19% yield.241 The corresponding 6-deoxy-6-fluoride was obtained in 60% yield by treatment of l,2 3,4-di-0-isopropylidene-a-D-galactopyranose 6-(dipropylphosphinite) with hexafluoropropene.242 The mechanism of this reaction has been discussed.243,244 In contrast, treatment of 1,2 -.3,4-di-O-isopropylidene-a-D-galactopyranose 6-(tetraethylphosphorodiamidite) with benzoyl fluoride yielded the corresponding 6-benzoate, not the 6-deoxy-6-flu-oride expected.245... 

In the particular case of 6-0-(dimethylthiocarbamoyl)-l,2 3,4-di-0-iso-propylidene-a-D-galactopyranose, the reported yields of the 6-deoxy and the 6-hydroxy products were 25 and 35%, respectively (see Scheme 13). 

Chloro-6-deoxy-l,2 3,4-di-0-isopropylidene-a-D-galactopyranose has been obtained in 96% yield by treatment of l,2 3,4-di-0-isopropylidene-6-0-p-tolylsul-fonyl-a-D-galactopyranose with lithium chloride inN,N-dimethylformamide [see K. W. Buck and A. B. Foster,/. Chem. Soc., 2217 (1963)]. 

Kent and coworkers98 have reported that N-(2-chloro-l,l,2-tri-fluoroethyl)diethylamine (51) reacts with l,2 3,4-di-0-isopropylidene-a-D-galactopyranose (42) in N,N-dimethylformamide at 60°, in the presence of anhydrous potassium fluoride, to give a mixture from which 6-chloro-6-deoxy-1,2 3,4-di-O-isopropylidene-a-D-galactopyra-... 

In order to obviate the formation of a formic ester, the reaction of l,2 3,4-di-0-isopropylidene-a-D-galactopyranose (42) was performed in p-dioxane. The 6-chloro-6-deoxy derivative (45) was again obtained, but only in low yield the major product was assigned the novel structure of 6-0-(4,6-dichloro-l,3,5-triazin-2-yl)-l,2 3,4-di-0-isopropylidene-a-D-galactopyranose (54). 

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