Amino-2-deoxy-D-galactose

The recent researches of Jeanloz6 have made available most of the (theoretically possible) methylated derivatives of 2-amino-2-deoxy-D-galactose. 

Borohydride reduction of 2-acetamido-2-deoxy-D-galactose affords 2-acetamido-2-deoxy-D-galactitol,219 whereas oxidation of the benzyl 2-(N-benzyloxycarbonyl)amino or-D-glycoside with oxygen in the presence of platinum oxide, followed by hydrogenolysis of the blocking groups, yields 

2-amino-2-deoxy-D-galacturonic acid.220 The former derivative may be of value in structural investigations on mucopolysaccharides,194 and the latter is important since 2-amino-2-deoxy-hexuronic acids occur naturally.63 

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Another microbial polysaccharide-based emulsifier is Hposan, produced by the yeast Candida lipolytica when grown on hydrocarbons (223). Liposan is apparentiy induced by certain water-immiscible hydrocarbons. It is composed of approximately 83% polysaccharide and 17% protein (224). The polysaccharide portion consists of D-glucose, D-galactose, 2-amino-2-deoxy-D-galactose, and D-galacturonic acid. The presence of fatty acyl groups has not been demonstrated the protein portion may confer some hydrophobic properties on the complex. 

Amino-2-deoxy-D-galactose (D-galactosamine chondrosamine) H HO HO H HOHjC—C—C—C—C—CHO HO H H NH, frog-spawn mucin blood-group substances cartilage... 

M. W. Homer, L. Hough, and A. C. Richardson, Selective benzoylation of methyl 2-benzamido-2-deoxy-a-D-glucopyranoside A convenient preparation of derivatives of 2-amino-2-deoxy-D-galactose, /. Chem. Soc., Sect. C (1970) 1336-1340. 

An original approach to the analysis of amino sugars has been proposed, based on their reaction with nitrous acid and subsequent reduction of the products with borohydride.564 By this procedure, 2-amino-2-deoxy-D-glucose and 2-amino-2-deoxy-D-galactose are converted into 2,5-anhydrohexitols, whereas 2-amino-2-deoxy-D-mannose yields D-glucitol. This mixture is readily separated after trimethyl-silylation. 

Fraction Mol. wt. D-Mannose D-Galactose L-Fucose D-Glucose Total neutral sugar 2-Ami no-2-deoxy-D-glucose 2-Amino-2- deoxy-D- galactose Total hexo- samine Sialic acid Total sugar Refer- ences... 

Baddiley and coworkers used V-deacetylation-deamination in structural studies on two oligosaccharides containing 2-amino-2-deoxy-D-galactose that had been obtained by dephosphorylation of the capsular substances from Pneumococcus types 10A (Ref. 177) and 29 (Ref. 13), respectively. The former (110) yielded 2-O-a-D-galac-... 

M. L. Wolfram and K. Onodera, Dithioacetals of D-gtucuronic add and 2-amino-2-deoXy-D-galactose, J. Am Chan. Soc. 79-ATV1 (1937). 

Fig. 12.—Degradation to Establish the Stereoohemical Series of 2-Amino-2-deoxy-D-galactose Residues by Converting C-l to C-3 into Serine.

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