Epimino sugar

Saccharides Containing Aziridine Rings (Epimino Sugars).352... 

Sugar azides are also important starting-materials for the synthesis of epimino sugars an azido group adjacent to a p-tolylsulfonyloxy group, as in 6 or 8, may be simultaneously reduced and cyclized with Raney nickel to form an aziridine ring, as in 7, especially if the two groups are in the frans-diaxial position.19 22... 

A number of epimino sugars have been prepared by the action of lithium aluminum hydride in tetrahydrofuran on vicinal benzamido sulfonates oriented in the trans relationship. Treated in this way, methyl 3 - benzamido -4,6-0 -benzylidene - 3 - deoxy -2-0- (methylsul-fonyl)-a -D-altropyranoside afforded - methyl 4,6-O-benzylidene-... 

Most epimino sugars are relatively stable in neutral or basic conditions. They are usually stable in the presence of such hydride reductive reagents as lithium aluminum hydride or sodium borohydride. They tend to undergo cleavage reactions or decompose in the presence of acids. A-Acylated aziridines are prone to lose the A -acyl substituent in the presence of nucleophiles and bases, and caution must be taken when nucleophilic cleavage of the aziridine ring of N-acylated epimines is to be performed. 

The structure of epimino sugars may be demonstrated by spectroscopic means. NMR spectroscopy is the technique most frequently used for determining of the structure of epimines, particularly their conformation in solution. The existence of hydrogen bonds has been evidenced by IR spectroscopy. 

R. D. Guthrie and D. Murphy, Nitrogen-containing carbohydrate derivatives. Part VII. Ringopening reactions of epimino-sugars, J. Chem. Soc. (1965) 3828-3834. 

U. Spohr and W. Mayer zu Reckendorf, Diamino and polyamino sugars. 30. Reaction of a 2,3-anhydro sugar with an 6-amino sugar, synthesis and reactions of a A-(glycos-6-yl)epimino sugar, Liebigs Ann. (1982) 1375-383. 

Hydrolysis of 2-amino-1,6 3,4-dianhydro-2-deoxy-j8-D-galactopyranose (142) with alkali gave, in addition to 2-amino-l,6-anhydro-2-deoxy-j3-D-glucopyranose, the isomeric epimino-sugar (143), although this isomerization did not occur at room temperature (c/. l,6 3,4-dianhydro-jS-D-galactopyranose). 

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