Of 2-amino-2-deoxy-D -glucose

Amino-sugars and Related Compounds. Part II. Observations on the Acidic Hydrolysis of Derivatives of 2-Amino-2-deoxy-D-glucose (D-Glucosamine), A. B. Foster, D. Horton, and M. Stacey,... 

Among the spectroscopic methods applicable to polysaccharides, u.v. spectrophotometry is of little value for characterizing heparin, whose main, electronic chromophore (the C02 group) displays a band at 220 nm, that is, in a region where all glycosaminoglycans absorb (also through their N-acetyl chromophores), and where minor proportions of unsaturated or aromatic contaminants cause serious interference.77 With pure heparin preparations, the carboxylate chromophore is most useful for chiroptical measurements, and a semi-quantitative evaluation of the extent of N-acetylation of 2-amino-2-deoxy-D-glucose residues is also possible.78... 

Scheme 2. — Nitrous Acid Deamination of 2-Amino-2-deoxy-D-glucose and Its Glycosides.

Garg and Jeanloz85,129 131 made extensive use of this procedure in order to obtain L-serine-containing mono-, di-, and tri-glycopeptide derivatives of 2-amino-2-deoxy-D-glucose. Thus, treatment of 6 with the... 

In a study of the oxidation of 2-amino-2-deoxy-D-glucose (D-glucosamine) derivatives, Neuberger12 obtained better results using sodium metaperiodate (at its accompanying pH of 3 to 4) than with periodic acid at lower pH values and a pH of 4.5 was found by Jeanloz and Forchielli78a to be optimal for these derivatives. 

V. Reactions of 2-Amino-2-deoxy-d-glucose with Dicarbonyl Compounds... 

The reaction of 2-amino-2-deoxy-D-glucose (D-glucosamine) with a dicarbonyl compound was carried out for the first time by Pauly and Ludwig,91 who were trying to discover how pyrrole rings in natural products are formed. They heated free D-glucosamine and ethyl acetoacetate on a steam bath and obtained a substance in which the presence of the pyrrole ring was demonstrated by the pine-splinter test. 

In analogy with the deamination of aminocyclohexanes,17-21 it has been found that the deamination, with nitrous acid, of 2-amino-2-deoxyaldohexoses in which the amino group has an equatorial orientation leads to 2,5-anhydrohexoses, as exemplified by the deamination of 2-amino-2-deoxy-D-glucose (10) to 2,5-anhydro-D-mannose22-25 (11). 

The preparation of several glucofuran [2, l-t/] oxazolines 35 and 36 from reaction of 2-amino-2-deoxy-D-glucose 34 with HF has been described. Compounds 35a and 35b are formed when the reaction is carried out in formic acid, whereas the orthoesters 36a-c are formed when the reaction is carried out using anhydrides. Further reaction of 35 and 36 with methanol gives methyl glycosides. Thus, 35 and 36 may hnd use as potential glycosyl donors for the synthesis of 2-amino-2-deoxy sugars (Scheme 8.14). " ... 

Fermentation procedures for preparing uridine 5 -(2-acetamido-2-deoxy-a-D-glucopyranosyl pyrophosphate) have also been reported. One of them255 involves the cultivation of Helminthosporium sativum in the presence of 2-amino-2-deoxy-D-glucose and the antibiotic polyoxin the latter is an inhibitor of chitin biosynthesis. The other256 utilized the incubation of yeast cells with uridine 5 -phosphate in the presence of an excess of 2-amino-2-deoxy-D-glucose and inorganic phosphate.257... 

The intravenous injection of 2-amino-2-deoxy-D-glucose-14C into rats, and subsequent isolation of the uridine diphosphate N-acetyl-hexosamine fraction, has been suggested as a fast and convenient method for preparing small amounts of a mixture of radioactive uridine 5 -(2-acetamido-2-deoxy-a-D-gIucopyranosyl pyrophosphate) and uridine 5 -(2-acetamido-2-deoxy-a-D-galactopyranosyl pyrophosphate). 

In attempting to obtain 2,5-anhydro-D-glucose diethyl dithioacetal, Defaye58 performed the nitrous acid deamination of 2-amino-2-deoxy-D-glucose diethyl dithioacetal (27) under weakly acidic conditions (acetic acid and sodium nitrite), and obtained a principal product later shown59 to be ethyl 2-S-ethyl-l,2-dithio-a-D-mannofuranoside (28). Shortly before, Horton and coworkers60 had reported the forma-... 

This reaction has been compared81 with the nitrous acid deamination of 2-amino-2-deoxy-D-glucose attack by a bromonium ion could lead to an intermediate, alkyl-iodonium cation (2-C-I-Br) , which would decompose through nucleophilic attack by 0-5, which is antiparallel to the leaving group at C-2. 

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