Sugars amino, deamination

Amino-sugars and Related Compounds. Part I. The Deamination of D-Glucosamine Hydrochloride, B. C. Bera, A. B. Foster, andM. Stacey,/. Chem. Soc., (1956) 4531-4535. 

More-specific methods are available for identifying and quantitating the typical, amino sugar component of heparin (and some heparan sulfate species), namely, 2-deoxy-2-sulfoamino-D-glucose. Most of these methods are based on conversion of these residues into 2,5-anhydro-D-mannose by deamination with nitrous acid (see Section VIII,2). The 2,5-anhydro-D-mannose residues may be determined either colorimetrically,52-54 or fluorimetrically.55... 

The chemistry of the 2,5-anhydrides of aldoses subsequently entered a prolonged lull, and Peat s review21 of 1946 in this Series does not report on any work later than 1925. The experimental basis of the deamination of amino sugars with nitrous acid was, nevertheless, established. The progress afterwards made in the conformational analysis of sugars made it possible for Shafizadeh22 to draw a parallel with the nitrous acid deamination of the aminocyclohexanols, and to rationalize the whole of these results. 

Undoubtedly, the vicinal groups play a fundamental role in the outcome of this reaction, especially with the sugars, where the favored conformation of the molecule at equilibrium is controlled at the outset by groups that determine whether the molecule exists as a cyclic or acyclic structure. The deamination of cyclic and acyclic amino sugar derivatives by nitrous acid will be considered in turn. 

In a discussion of the use of deamination to obtain structural information, it is convenient to consider two different aspects (a) applications to monosaccharide and cyclitol amines, and (b) applications to compounds containing amino sugar and inosamine residues. The latter compounds would include oligosaccharides, polysaccharides, glycolipids, glycoproteins, and antibiotics. 

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