2-deoxyglycoside

Oxidation of 2-deoxyglycosides with the chromium peroxide-pyridine... 

Of the many methods described for glycoside synthesis, those predominantly used in current oligosaccharide synthesis, in which the glycosyl donor has O- or N- functionality at C-2 (that is, excluding 2-deoxyglycosides), are the following ... 

Deoxyglycosides are, in spite of the 2000-fold greater sensitivity against acid hydrolysis, only poor substrates for glycosidases, as shown by the... 

Glycals have been widely used as glycosyl donors, especially for the synthesis of 2-deoxyglycosides 45b 47 In addition, they can be readily converted into 2,3-unsaturated... 

In brief, a wide range of 2-deoxyglycosides are available from glucals, either directly using proton or Lewis acids together with nucleophiles, or by haloalkoxyla-tion with subsequent reductive removal of the halide at C-2. 

Oxazoline glycosyl donors are generally prepared from the corresponding 2-acylamido-2-deoxyglycosides by the activation of the C-l leaving group using an... 

Yet another hetero-dien for cycloaddition reactions of glycals that had been used for the preparation of 2-deoxyglycosides is 2,4-dioxo-3-thioxo-pentane, generated in situ from 3-thiophthalimido-pentane-2,4-dion. The cycloaddition occurs with high... 

Glycals, for example D-glucal (23), being vinyl ethers are susceptible to acid catalysed additions of alcohols which result in the formation of 2-deoxyglycosides, but elimination reactions accompany additions of this type 86) go such products are better prepared by way of halogen adducts or by the alkoxymercuration reaction (see below). On the other hand, the addition procedure can be more suitable than the alcoholysis... 

The reductive lithiation of a-alkoxy phenylsulfides is a slow process (typically 0.5-1 h at -78°C) and lowering the LUMO of the electron acceptor by using, for example, an anomeric sulfone, leads to a much faster electron transfer [11]. Reductive lithiation of sulfone 22 is fast (less than 1 min) and leads to similar a-lithio reagents to those described above and Scheme 8 shows examples of simple a-C-2-deoxyglycosides 23 and 24 prepared by this protocol. The most interesting feature of anomeric sulfones is that alkylation prior to the reductive desulfonylation event is achievable. In this way, a one-pot four-step sequence... 

Y. Ito and T. Ogawa, Sulfenate esters as glycosyl acceptors A novel approach to the synthesis of 2-deoxyglycosides, Tetrahedron Lett. 28 2123 (1987). 

The reaction produces a stereoselective synthesis of a- or (S-2-deoxyglycosides. a-Linked disaccharides such as 1 can be prepared by a three-step sequence with high stereocontrol. 

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