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Heparin nitrous acid deamination

Both positional linkages (uronic acid to hexosamine and hexosamine to uronic acid) were established as being (1 — 4) by structural analysis of the previously mentioned (see Section IV), crystalline disaccharides containing D-glucuronic acid, isolated from an acid hydrolyzate of carboxyl-reduced heparin.128-129 Further evidence was obtained from the structure of the D-glucuronic acid-containing counterpart of disaccharides 6 and 8, obtained as minor products from pig-mucosal heparin following nitrous acid deamination,1110 136-138 and acid hydrolysis followed by N-acetylation,130 respectively. [Pg.72]

Nitrous acid deaminations have been invaluable in the investigation of the structure of heparin.85,236-253 The potential value of de-... [Pg.73]

A sensitive fluorimetric assay for 2-amino-2-deoxy-D-hexoses with increased sensitivity over the Elson-Morgan and Dische-Borenfreund indole methods has been reported. The 2,5-anhydrohexoses produced by nitrous acid deamination of heparin, heparan sulphate, and 2-amino-2-deoxy-D-hexoses have been treated with 3,5-diaminobenzoic acid to give stable derivatives. Neither neutral sugars nor acetamido sugars interfere in the reaction. In a modification of an earlier procedure, equivalent colour complexes were formed by the interaction of 3-methyl 2-benzothiazoline and the 2,5-anhydrohexoses produced by deamination of 2-amino-2-deoxy-D-glucose and 2-amino-2-deoxy-D-galactose. ... [Pg.242]

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... [Pg.62]

The scope of the deamination reaction was extended to the characterization of heparin segments containing 2-acetamido-2-deoxy-D-glucosyl residues by removing (by hydrazinolysis) the N-acetyl groups and cleaving with nitrous acid (at pH 4) the otherwise resistant segments.113,232... [Pg.89]

As acetamido groups do not react with nitrous acid under the usual conditions, it was possible to identify 2-acetamido-2-deoxy-D-glucose residues in heparin after deamination,244 and their distribution was... [Pg.74]

See other pages where Heparin nitrous acid deamination is mentioned: [Pg.70]    [Pg.76]    [Pg.86]    [Pg.87]    [Pg.70]    [Pg.76]    [Pg.86]    [Pg.87]    [Pg.41]    [Pg.68]    [Pg.87]    [Pg.74]    [Pg.75]    [Pg.75]    [Pg.232]    [Pg.211]    [Pg.213]    [Pg.358]    [Pg.263]    [Pg.610]    [Pg.68]   
See also in sourсe #XX -- [ Pg.31 , Pg.43 , Pg.62 , Pg.73 , Pg.74 , Pg.86 , Pg.87 , Pg.88 , Pg.89 , Pg.90 , Pg.91 , Pg.92 , Pg.93 , Pg.94 ]



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