C. Duke, J. Macleod, John F. Williams
Sep 1, 1981
Citations
0
Influential Citations
20
Citations
Journal
Carbohydrate Research
Abstract
Abstract N.m.r. studies show that a concentrated (∼ 1.0 M ) aqueous solution of d -erythrose 4-phosphate is composed of an equilibrium mixture of the monomeric aldehyde and hydrated aldehyde forms, which interconvert rapidly, together with a major contribution from three dimeric forms. In dilute solutions (∼0.04 M ), the hydrated monomer is predominant and dimeric forms are not detectable at this concentration. The chemical structures and stereochemistry of the three dimers have been elucidated by 1 H- and 13 C-n.m.r. spectroscopy of d -erythrose 4-phosphate and its (4,4- 2 H 2 ) and (3,4,4′- 2 H 3 ) derivatives, aided by the use of the model compounds, glycolaldehyde, d -glyceraldehyde, and dL -glyceraldehyde 3-phosphate, which also form dimers in concentrated aqueous solution. In some cases, the tert -butyldimethylsilyl derivatives of the model dimeric compounds were prepared and isolated. The two major dimers of d -erythrose 4-phosphate, I and II, are asymmetrically substituted 1,3-dioxane and 1,3-dioxolane structures, respectively, and dimer III is the α anomer of dimer I.