Anhydro amino sugar

Amino-sugars and Related Compounds. V 2-Amino-l,6-anhydro-2-deoxy- 3-D-altropyranoside hydrochloride, A. B. Foster, M. Stacey, and S. V. Vardheim, Acta Chem. Scand., 12 (1958) 1605-1610. 

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 identification of L-iduronic acid as the major glycuronic acid constituent of heparin proved to be a much slower process than the identification of the amino sugar residue. Although this compound was detected in acid hydrolyzates of heparin116117 and heparin oligosaccharides,118 its yield was usually poor, because of the drastic conditions used for the acid hydrolysis (which are known to lead to extensive destruction of uronic acid).119120 Also, L-iduronic acid escaped detection as L-idose in the hydrolyzates of carboxyl-reduced heparin, probably because L-idose is readily converted into 1,6-anhydro-L-idose under the usual hydrolytic conditions. 

From pig mucosa. Notations as for Scheme 1. Major products (yield 40-80% of original heparin). Major disaccharide fraction (50-80%). From heparin chains terminating with a D-glucuronic acid residue at the reducing end. Minor products (yield <3% of original heparin). From the active site for antithrombin (asterisk denotes 3-C-sulfation of the amino sugar or anhydro-D-mannose). 

Tables V-LVII detail H and F shift and coupling information, and Tables LVIII to LXXI incorporate the C-n.m.r. data. The data within this compilation are arranged according to the following outline hexoses prior to pentoses, followed by anhydro sugars, sugar acids and lactones, amino sugars (and their synthetic, A -containing precursors), mono-, di-, and tri-deoxy sugars, branched derivatives, ketoses, polyfluorinated monosaccharides, and, finally, difluorinated amino sugars. Within this compilation, and even within each table, pyranoid derivatives are listed prior to their furanoid counterparts, hexoses prior to pentoses, functionalized prior to deoxy compounds the arrangement within each sub-table is made alphabetically.

C-6,209,214 anhydro sugars,branched monosaccharides, fluori-nated amino sugars,difluorinated monosaccharides, and fluorinated monosaccharide phosphates,and phosphonates have been described. Further progress has been achieved in the synthesis and n.m.r.-spectral analysis of fluorinated avermectin Bu, tylono-lide, and neuraminic acid derivatives. " ... 

Anhydromannitol, 2,5-anhydro-3-O-methyl-mannitol, 2,5-anhydro-talitol 5% SE-30 170-190 amino sugars + HN02 564... 

C-3 in the unsubstituted compound.176,177 However, at the time of these experiments, only C-3 substitution had been observed with 2,3-anhydropentofuranosides, and the results of investigation of this reaction suggest that the amino sugar substituted at C-2 is the major product.184 With thiocyanate ion, substitution also occurs at C-3, leading to the thietane derivative, namely, methyl 3,5-anhydro-3-thio-a-D-xylofuranoside (59) but, as this compound was obtained in only 25% yield, the major pathway may involve 2-substitution, leading to products not characterized.178... 

Although 2,5-anhydro sugars had, for a long time, been poorly understood, they have now found useful application as intermediates in synthesis, and even as derivatives for the characterization of certain amino sugars. For example, a useful method for the analytical deter-... 

M. Jezowska-Bojczuk, H. Kozlowski, T. Trnka, and M. Cerny, Interaction of 1,6-anhydro derivatives of amino sugars with copper(II) ions, Carbohydr. Res., 253 (1994) 19-28. 

T. Uryu, K. Hatanaka, K. Matsuzaki, and H. Kuzuhara, Synthesis of stereoregular polysaccharides having amino-groups by ring-opening copolymerization of 1,6-anhydro-azido-sugar derivatives, J. Polym. Sci., Part A Polym. Chem., 21 (1983) 2203-2214. 

J. Jary and K. Capek, Amino sugars. 5. Preparation of methyl-3,4-anhydro-6-deoxy-a-D-galactopyranoside derivatives, Collect. Czech. Chem. Commun., 31 (1966) 315-320. 

C. A. Johnson and P. H. Gross, Heterocyclic amino sugar derivatives. 6. Stabilization of a reactive intermediate by steric hindrance. Mechanism of 3,6-anhydro sugar formation, J. Org. Chem., 38 (1973) 2509-2512. 

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