Glucosylamine acetylation

For the N-acylaldobiosylamines, this method requires a second oxidation and further reduction, as shown for N-acetyl-6-O-a-D-galactopyranosyl-/3-D-glucosylamine (N-acetyl-/3-meIibiosylamine)49 (54) in the following sequence. 

Oxidation of N-Acetyl-D-glucosylamine.98 Six grams (0.027 mole) of N-acetyl-D-glucosylamine (XLI) in 100 cc. of water is added to 18.5 g. (0.081 mole) of paraperiodic acid in 100 cc. of water, and the reaction mixture is maintained at 25° for four and one-half hours, which is known from analytical data obtained in small-scale experiments to be sufficient time for completion of the reaction with the consumption of two moles of the oxidant. The solution is exactly neutralized with barium hydroxide, the precipitate removed, and the filtrate evaporated to dryness in vacuum. The solid is extracted with 100 cc. of absolute ethanol, the ethanol extract evaporated to dryness, the residue taken up in ethanol, and the solution is centrifuged and again evaporated to dryness. The product, the dialdehyde XLII, can be converted into the corresponding barium salt (see reference 93). 

N-Acetyl-D-glucosylamine (XLI). Acetamino-D-hydroxymethyl diglycolic aldehyde (XLII) " 93... 

Deacetylatioii of the esters, which proceeds normally, has been siu cess-fully carried out with ammonia, sodium methoxide, or barium methoxide in methanol. In this way, for example, iV-p-tolyl-/8-D-glucosylamine 2,3,4,()-tetraacetate is converted into iV -p-tolyl-/8-D-gluoosylamine, and iV-acetyl-/8-D-galactosylamine tetraacetate into iV-acetyl-/8-D-galactosyl-amine. ... 

Niemann and Hays later showed that the oxidation of one mole of iV-acetyl-D-glucosylamine by lead tetraacetate involves the slow consumption of slightly more than two moles of oxidant, so confirming the result of periodate oxidation. Hockett and Chandler prepared an isomeric N-acetyl-D-glucosylamine, also cyclic since it gives a tetraacetate, by the action of 29 % aqueous ammonia on aldehydo-D-glucose pentaacetate or on hexa-0-acetyl- a -D-glucoheptonic nitrile. The oxidation of this isomer produced formaldehyde (isolated as its 2,4-dinitrophenylhydrazone), but... 

The first observation on the reactions of glycosylamines with 3-dicarbonyl compounds is due to Elson and Morgan, who found that D-glucosylamine and 2,4-pentanedione, when heated in slightly alkaline solution, give a positive Ehrlich pyrrole test. They considered that 3-acetyl-2-methyl-4-(D-ara6wo-tetrahydroxybutyl)pyrrole (20) was formed and was responsible for the color reaction. 

Tetra-Ac, H-formyl 2,3,4,6-Tetra-O-acetyl-N-formyl-P-D-glucosylamine Q5H21NO10 375.332... 

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