Synthesis of vitamin B6 derivatives. III. 3‐ (4‐formyl‐3‐hydroxy‐2‐methyl‐5‐pyridyl)propionic acid, an analog of pyridoxal phosphate

Abstract

AbstractThe preparation and properties of a new analog of pyridoxal phosphate, 3‐ (4‐formyl‐3‐hydroxy‐2‐methyl‐5‐pyridyl)propionic acid and of the corresponding 4‐aminomethyl compound are described. The n.m.r. spectrum of the new aldehyde is compared with those of 5‐deoxypyridoxal and pyridoxal phosphate. The broad aldehyde proton peak of 5‐deoxypyridoxal is sharpened by heating, suggesting an equilibrium between two geometrical isomers. Mass spectra of the new aldehyde and of 5‐deoxypyridoxal are analyzed. The electronic absorption spectrum is nearly the same as that of 5‐deoxypyridoxal. The new aldehyde undergoes rapid transamination with amino acids, and the corresponding aminomethyl compound can be reoxidized to the aldehyde by heating with glyoxylic acid in aqueous solution.