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Diβ- d -glucopyranosylamine ( 2 ) was prepared by transglycosylation from β- d -glucopyranosylamine. O -Acetylation of 2 led to partial anomerization and the formation of the expected octa- O -acetyl β,β derivative and its α,β anomer in the ratio 1:2.4. Similarly, transglycosylation of β- d -xylopyranosylamine afforded di-β- d -xylopyranosylamine ( 7 ). As with 2 , the O -acetylation of 7 led to partial anomerization and formation of the hexa- O -acetyl α,β anomer of 7 , as well as the expected β,β O -acetylated derivative. O -Deacetylation with ammonia in methanol of (2,3,4-tri- O -acetyl-α- d -xylopyranosyl)(2,3,4-tri- O -acetyl-β- d -xylopyranosyl)amine ( 7 ) led to recovery of the β,β-linked starting material. These rearrangement reactions are interpreted in terms of unfavorable nonbonded interactions which modify the thermodynamic equilibrium of the diglycosylamines.

The secondary hydroxyl groups of d -arabinitol and xylitol were shown to undergo oxidation with a boiling, methanolic solution of mercury(II) acetate to give d - threo -pentulose, d - threo -3-pentulose, d - erythro -pentulose, and dl - threo -pentulose and erythro -3-pentulose, respectively. The formation of dihydroxyacetone and dl -glyceraldehyde from glycerol, and mainly glycolaldehyde from ethylene glycol, indicates that primary hydroxyl groups are also oxidised. These results, as well as the formation of acetone upon treatment of isopropyl alcohol with mercury(II) acetate, indicate that cyclic intermediates are not involved in these oxidations.

A method has been developed for studying the enolization of sugars in D2O, and determining by infrared absorption the DOH formed. The method does not require isotopically labeled substrates and does not involve a primary isotope-effect. It can be applied to reducing sugars in general and to diverse reaction-systems. By use of radioactivity measurements in conjunction with measurements of infrared absorption, the isotope effect kT/kH, for the release of hydrogen atoms from deuterated d -glucose-2-t, was measured and found to be 0.13.