Syntheses of labeled vitamers of folic acid to be used as internal standards in stable isotope dilution assays

J Agric Food Chem. 2002 Aug 14;50(17):4760-8. doi: 10.1021/jf025571k.


[2H4]Folic acid was synthesized by deuterating p-aminobenzoic acid, which was then coupled to glutamic acid and 6-formylpterin. Using [2H4]folic acid as starting component enabled the preparation of labeled vitamers tetrahydrofolate, 5-formyltetrahydrofolate, 5-methyltetrahydrofolate, and 10-formylfolate which were characterized by electrospray mass spectrometry and collision-induced dissociation. The mass spectrometric studies confirmed that the compounds could be used as internal standards in stable isotope dilution assays.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 4-Aminobenzoic Acid / chemistry
  • Chromatography, High Pressure Liquid
  • Deuterium*
  • Folic Acid / analogs & derivatives*
  • Folic Acid / chemical synthesis*
  • Glutamic Acid / chemistry
  • Isotope Labeling / methods*
  • Leucovorin / chemical synthesis
  • Magnetic Resonance Spectroscopy
  • Pteridines / chemistry
  • Pterins*
  • Spectrometry, Mass, Electrospray Ionization
  • Tetrahydrofolates / chemical synthesis


  • Pteridines
  • Pterins
  • Tetrahydrofolates
  • 10-formylfolic acid
  • Glutamic Acid
  • 5,6,7,8-tetrahydrofolic acid
  • 2-amino-4-hydroxy-6-formylpteridine
  • Folic Acid
  • Deuterium
  • Leucovorin
  • 4-Aminobenzoic Acid
  • 5-methyltetrahydrofolate