Abstract
The following nicotinic acid derivatives of the vitamin B_6 group have been prepared : Pyridoxine-5-nicotinate, pyridoxine-4,5-dinicotinate, 4-nicotinylpyridoxamine-5-nicotinate, 4-nicotinylpyridoxamine, pyridoxamine-5-nicotinate and pyridoxal-5-nicotinate. The ultraviolet absorption spectra of these compunds are essentially identical, with the exception of that of pyridoxal-5-nicotinate, which is distinguished by having a maximum at 390mμ in phosphate buffer (pH 7.0) as a solvent. Pyridoxine-5-nicotinate and pyridoxine-4,5-dinicotinate showed the vitamin B_6 activity for Sacch. carlsbergensis.
