Carbohydrates, deoxy, synthesis

Carbenoid cyclopropanation, 57, 1 58, 1 Carbohydrates, deoxy, synthesis of, 30, 2 Carbo/metallocupration, 41, 2 Carbon-carbon bond formation ... 

This reaction has found widespread application in organic synthesis, especially in the preparation of deoxy carbohydrates, deoxy nucleosides, and nucleotides. In addition, this reaction can also be applied for converting aldehydes/ketones to alkanes after the reduction of the carbonyl groups. Unfortunately, this reaction has failed in a few... 

There has been a further carbohydrate-based synthesis of the epoxide (+)-disparlure, the gipsy moth pheromone, using 2-deoxy-D-ribose as starting material and epoxyalcohol intermediates. (14S, 15S)-Leukotriene A4 methyl ester (58) has been prepared using the synthon (57), derived from D-glucal, as precursor, and epoxy alcohols were again used as intermediates. A synthesis of (+)-muscarine (59) from L-rhamnose is outlined in Scheme 10.46... 

Vasella has used deoxy-nitro sugars for the synthesis of various biologically important carbohydrates, and the radical nitromethyladon of deoxy-nitro sugars has been used for synthesis of fnictose 6-phosphate" and 6-C-methyl and 6-C-rhydroxymethyl analogiies of iV-acetylnenraitinic acid fsee Scheme7.2. ... 

The Oxidation of Some Carbohydrate Derivatives using Acetic Anhydride - Methyl Sulphoxide Mixtures and the Pfitzner-Moffat Reagent. Facile Synthesis of 3-Acetamido-3-deoxy-D-glucose and 3-Amino-3-deoxy-D-xylose, J. S. Brimacombe, J. G. H. Bryan, A. Husain, M. Stacey, and M. S. 

Nucleophilic Displacement Reactions in Carbohydrates. Part XI. Reaction of Methyl 6-Deoxy-2,3-O-isopropylidene-4-O-methyl-sulphonyl-a-L-talopyranoside with Sodium Azide A Synthesis of L-Perosamine (4-Amino-4,6-dideoxy-L-mannose) Derivatives, J. S. Brimacombe, O. A. Ching, and M. Stacey, J. Chem. Soc. C, (1969) 1270-1274. 

Because sugars are involved in most of the mechanisms established for the synthesis of these heterocycles, the development of carbohydrate chemistry has been most helpful in these researches—especially for the preparation of specifically labeled molecules. Conversely, the contribution of these efforts to carbohydrate chemistry and biochemistry has shown the involvement in biosynthesis of 1 -deoxy-D-f/rreo-pentulose—scarcely before recognized and considered a rare sugar—and of fully functionalized pentuloses of still unknown configuration (or their phosphates). Finally, evidence has been found in prokaryotes for a most extraordinary transformation of 5-amino-l-(P-D-ribofuranosyl)imidazole 5 -phos-phate into a pyrimidine. Surely, this transformation should be explained in terms... 

R. M. de Lederkremer and C. Marino, Deoxy sugars occurrence and synthesis, Adv. Carbohydr. Chem Biochem., 61 (2007) 148-151. 

M. A. Probert, J. Zhang, and D. R. Bundle, Synthesis of a- and /blinked tyvelose epitopes of the Trichinella spiralis glycan 2-Acetamido-2-deoxy-3-0-(3, 6-dideoxy-D-arabmo-hexopyninosyl)-/)-D-galactopyranosides. Carbohydr. Res., 296 (1996) 149-170. 

Synthesis from carbohydrate derived 2-deoxy lactones. Routes to C-l glycals from 2-deoxy sugar pyranolactones have been described. The general strategy is outlined in Scheme 9. 

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... 

The availability, in gram quantities, of the fluorinated carbohydrates thus far synthesized has also made possible their use as starting materials for the synthesis of other analogs and intermediates for example, the preparation of 3,5-dideoxy-3,5-difluoro-D-xylose from 3-deoxy-3-fluoro-D-xylose,88 which is itself preparable from 3-deoxy-3-fluoro-l,2-0-isopropylidene-a-D-glucofuranose. Electrolytic oxidation of 3-deoxy-3-fluoro-D-glucose afforded, after treatment with an acidic... 

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