Special Problems in Glycosylation Reactions 2-Deoxy Sugars

15 Special Problems in Glycosylation Reactions 2-Deoxy Sugars 

The synthetic aspects of the chemical construction of 2-deoxyglycosides have been the subject of four recent reviews [2-5]. 

2 Electrophilic Additions to Glycals Mechanistic Aspects and Applications to the Synthesis of 2-Deoxyglycosides 

If a true oxycarbenium ion is involved, one can expect that the stereoselectivity will be governed by the kinetic anomeric effect [6-8] leading to a predominant axial stereochemistry at C-1, the a/P ratio being of course modulated by steric effects (a 3-axial substituent can override the stereoelectronic effect). Oxycarbenium ions 2 and 3 lead to a-D-manno 6 and a-u-gluco 9 pyranosides respectively. Altogether, 2-deoxy-a-glycopyranosides can be predicted to be more easily attained after replacement of E by hydrogen. 

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Veyrieres A (2000) Special problems in glycosylation reactions 2-deoxy sugars. In Beat E, Hart GW, Sinay P (eds) Carbohydrates in chemistry and biology, vol 1. Wiley-VCH, Weinheim, p 367... 

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