4-Pyridoxic Acid
Structural Formula Vector Image
Title: 4-Pyridoxic Acid
CAS Registry Number: 82-82-6
CAS Name: 3-Hydroxy-5-(hydroxymethyl)-2-methyl-4-pyridinecarboxylic acid
Additional Names: 3-hydroxy-5-(hydroxymethyl)-2-methylisonicotinic acid; 2-methyl-3-hydroxy-4-carboxy-5-hydroxymethylpyridine
Molecular Formula: C8H9NO4
Molecular Weight: 183.16
Percent Composition: C 52.46%, H 4.95%, N 7.65%, O 34.94%
Literature References: Occurs in urine. It is the chief metabolic product of pyridoxine, pyridoxal, and pyridoxamine. Isoln from human urine: Singal, Sydenstricker, Science 78, 545 (1941). Isoln and synthesis: Huff, Perlzweig, J. Biol. Chem. 155, 345 (1944).
Properties: Wedge-shaped crystals, mp 247-248°. Slightly sol in water, alcohol, pyridine. Insoluble in ether and in aq acid soln, but completely sol in aq alkaline soln. Possesses two acidic groups, one a phenolic and the other a carboxyl having pK values of 9.75 and 5.50, respectively. Characteristic blue fluorescence, max at pH 3 to 4. The fluorescence disappears on reduction with hydrosulfite and is restored to the original intensity with H2O2. Is adsorbed on zeolite from aq solns at pH 4 to 5 and can be eluted with 25% KCl; butanol extracts of neutral eluates also show characteristic blue fluorescence which is increased by a trace of acetic acid. Stable to boiling with dil alkali (1N); but upon being heated with 0.5N acid for a few minutes it is converted to the lactone.
Melting point: mp 247-248°
pKa: pK values of 9.75 and 5.50, respectively
Derivative Type: Lactone
Additional Names: b-Pyracine
Molecular Formula: C8H7NO3
Molecular Weight: 165.15
Percent Composition: C 58.18%, H 4.27%, N 8.48%, O 29.06%
Properties: mp 263-265°, exhibits much stronger fluorescence. Is more easily followed in the course of biochemical investigations.
Melting point: mp 263-265°

Other Monographs:
Benzoic AcidMagnesium DiborideCaproyl ChlorideCollodion
KallikreinConquinamineThimerfonate SodiumPretilachlor
©2006-2023 DrugFuture->Chemical Index Database