2 -deoxy-/?-disaccharide

This improvement allowed achieving the synthesis of 2-deoxy disaccharide 103 with high stereoselectivity and good yield in short reaction times. The composition of the reaction mixture was found to be practically independent of the configuration of the S-(2-deoxy-D-glucopyranosyl)phosphorothioate. These results seem to provide an evidence that this glycosylation procedure proceeds via the SN1 displacement reaction mechanism. 

G. Janrand, J.-M. Beau, and P. Sinay, Glycosyloxyselenation-deselenation of glycals A new approach to 2 -deoxy-disaccharide, J. Chem. Soc. Chem. Commurt. p. 572 (1981). 

A. Koch, C. Lamberth, F. Wetterich, and B. Giese, Radical rearrangement of 2-0-(di-phenylphosphoryl)glycosyl bromides. A new synthesis for 2-deoxy disaccharides and 2-deoxy ribonucleosides, J. Org. Chem., 58 (1993) 1083-1089. 

Reductive removal of the phenylseleno group of 110 and 111 by triphenyl-tin hydride led to the 2 -deoxy-/3-D-disaccharides 112 and 113. Although these methodologies were reported several years ago, they have not often been employed to prepare a- to /3-linked 2-deoxy disaccharides. 

The selenophenyl substituent, which served as stereodirecting auxiliary (Section 4.2), was then removed to give the 2 -deoxy disaccharide 62. 

Ravi, D, Kulkami, V R, Mereyala, H B, A mild general-method for the synthesis of a-2-deoxy-disaccharides synthesis of L-oleandrosyl-L-oleandrose from D-glucose, Tetrahedron Lett., 30, 4287-4290, 1989. 

The synthesis of 7-deoxy-L-g/ cero-D-g/Mco-heptose (19), an inhibitor of gluco-kinase and glucose 6-phosphatase, from 1,2-0-isopropylidene-D-glucuronolac-tone derivative 18 is shown in Scheme 5. The 2 -0-cyclohexylcarbamoyl disaccharide 20 (see Chapter 3 for formation) was readily converted to the corresponding xanthate which was deoxygenated with tributyltin hydride to the 2 -deoxy disaccharide 21. Radical deoxygenation with tributyltin hydride has also been use to prepare l, 6 -dideoxysucrose from the corresponding l, 6 -ditriflate. ... 

Jaurand G, Beau J-M, Sinay P (1981) Glycosyloxyselenation-deselenation of glycals anew approach to 2 -deoxy-disaccharides. J Chem Soc Chem Conraiun 1981 572-573... 

An extensive report from Prinzbach s laboratory has described the synthesis of the pseudodisaccharide sannamycin (1), its 2-epimer and various other isomers, including the enantiomers of sannamycin and its 2-epimer. A detailed study was made of the glycosylations necessary to assemble these sytems. Various other novel pseudodisaccharides have also been prepared, including the a-D-arabino-furanosyl systems 2 (R=H, a-NHa, jJ-NHa), and the pyranose these workers also describe a Ferrier carbocyclization at the disaccharide level, using an acid labile 2 -deoxy-disaccharide, to give the aminocyclitol derivative 4. ... 

Tri-0-benzyl-2-deoxy-D-ara6mo-hexopyranose 151, easily obtained [10] from 3,4,6-tri-O-benzyl-D-glucal 29, was converted into an anomeric 7V,7V-diisopropyl phosphoramidite 152 which, under activation by TMS triflate at low temperatures, reacted with sugar alcohols to give 2 -deoxy disaccharides 153 in high yields and excellent a-stereoselectivity (Scheme 35) [101]. 

Graziani, A., PassacantiDi, P., Piancatelli, G., and Tani, S. (2000) 2-Deoxy-disaccharide approach to natural and unnatural glycos-phingohpids synthesis. Tetrahedron Asymmetry, 11, 3921-3937. 

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