Gluconic acid 824 glucosamine

Procedure Synthesis of Xylonic, Galactonic, Mannonic, 2-Deoxygluconic Acid and Synthesis of 2-Amino-2-deoxy-gluconic Acid (Glucosaminic Acid)... 

Further consideration needs to be given to the interesting fact that although D-glucosaminic acid (2-amino-D-gluconic acid) undergoes de-amination. with the establishment of a 2,5-anhydro ring, the deamination... 

An unusual classification of hexonic acids described by Levene21 was based on the differences in optical rotation between the free acid and its sodium salt. For example, in the D-gluconic acid series the sodium salt has the more positive rotation whereas in the D-mannonic acid group the reverse is the case and the acid has the more positive rotation. In comparison with these results glucosaminic acid was found to have a rotation of —15° (and its sodium salt +1.3°) and therefore these derivatives were in conformity with the D-gluconic acid series. 

It was pointed out that N-methyl-L-glucosaminic acid nitrile was only the second nitrile in the sugar series to be isolated in the cyanohydrin reaction and that extension of the general procedure by which it was prepared should result in the isolation of other members. The nitrile of N-methyl-L-glucosaminic acid showed the same unusual mutarotation as does that of the lower-melting form of D-gluconic acid nitrile. Wolfrom and Thompson have noted that N-methyl-L-glucosaminic acid nitrile hydrochloride was a much more stable compound than the free base. 

D-Glucosaminic acid (2-Amino-2-deoxy-D-gluconic acid)... 

Let us now return to the pioneering work of Fischer and Tiemann. Chitonic acid is produced from D-glucosamine by deamination and oxidation, in that order. If the order is reversed, however, i. e., if D-glucos-amine is first oxidized to D-glucosaminic acid (2-amino-D-gluconic acid) and the latter substance subsequently deaminated, chitonic acid is not the product. Instead an isomeric 2,5-anhydro hexonic acid (chitaric acid) is obtained. These facts may be summarized thus ... 

Synthesis of the 3,4,6-trimethyl ether of 2-deoxy-2-methylamino-n-gluconic acid was carried out along lines similar to those of the synthesis of the 3,6-dimethyl ether. By the addition of methylamine and hydrogen cyanide to 2,3,5-tri-O-methyl-n-arabinose, followed by hydrolysis, only one compound was formed, and this was related to n-glucosamine on the basis of its optical rotation. An attempt to obtain the aldose derivative by reduction with sodium amalgam was not successful, probably because of the impossibility of 5-lactone formation. 

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