TRIS BUFFER REACTIVITY WITH LOW-MOLECULAR-WEIGHT ALDEHYDES - NMR CHARACTERIZATION OF THE REACTIONS OF GLYCERALDEHYDE-3-PHOSPHATE

Tris (2-amino-2-hydroxymethylpropane-1,3-diol) reacts with aldehydes of low molecular weight in aqueous solutions to give products whose NMR spectral properties are inconsistent with the formation of the expected Schiff base. High-held H-1 and C-13 NMR spectra of a solution of Tris and glyceraldehyde 3-phosphate indicated initial formation of 2-(beta-phosphoglycolyl)-4,4-bis(hydroxymethyl)1,3-oxazolidine, which was then converted to condensation products of Tris and methylglyoxal, accompanied by deuterium exchange when the solvent was (H2O)-H-2. Acetaldehyde and benzaldehyde were used as model substrates which yielded more stable oxazolidines in their reactions with Tris. (C) Press Academic Press, Inc.