Oligosaccharide deoxyhexoses

The oligosaccharide components of glycoproteins are generally branched heteropolymers composed primarily of D-hexoses, with the addition in seme cases of neuraminic acid, and of L-fucose—a 6-deoxyhexose. 

Whilst there appears to be limited scope at present for the utilization of these observations in determinations of polysaccharide structures, they can be of value when the Morgan-Elson test is applied to oligosaccharides containing amino sugar residues, as the work on the oligosaccharides from human milk2 has shown. Obviously, no simple relation exists between a positive test and the presence of free 2-acetamido-2-deoxyhexose, but much information may be culled by a consideration of all the factors outlined above. 

For the synthesis of oligosaccharide units containing residues of configurationally accessible 6-deoxyhexoses, standard protecting-groups methodology has... 

The most easily recognizable fragment ions in the mass spectra of permethylated oligosaccharide alditols are those from nonreducing units, i.e., fragment ions at m/z 219 for permethylated hexose, m/z 189 for permethylated deoxyhexose, m/z 175 for permethylated pentose, m/z 233 for permethylated... 

Oligosaccharide-4 (11) established that the acid-labile fucosyl residue was attached to galactose. Although oligosaccharide-1 (11) was only found in small amounts, presumably because the Ara/residues are not as stable as 6-deoxyhexose to acetolysis, its presence suggests that it is an... 

Deoxyhexoses. A component of a few oligosaccharides of milk and of blood group substances (see Chapt. XVII-7) is h-fucose (6-deoxy-L-galactose). Rhamnose (6-deoxy-L-mannose) occurs in glycosides, e.g. in strophanthin. Note that both deoxyhexoses belong to the L-series. 

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