title: Syntheses of labeled vitamers of folic acid to be used as internal standards in stable isotope dilution assays.
abstract: [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.
authors.affiliation: Institut für Lebensmittelchemie der Technischen Universität München, Lichtenbergstrasse 4, D-85748 Garching, Germany.
authors.forename: Achim
authors.initials: A
authors.lastname: Freisleben
authors.forename: Peter
authors.initials: P
authors.lastname: Schieberle
authors.forename: Michael
authors.initials: M
authors.lastname: Rychlik
mesh_terms: D010129:4-Aminobenzoic Acid / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D003903:Deuterium; D005492:Folic Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis*; D018698:Glutamic Acid / Q000737:chemistry; D007553:Isotope Labeling / Q000379:methods*; D002955:Leucovorin / Q000138:chemical synthesis; D009682:Magnetic Resonance Spectroscopy; D011621:Pteridines / Q000737:chemistry; D011622:Pterins; D021241:Spectrometry, Mass, Electrospray Ionization; D013763:Tetrahydrofolates / Q000138:chemical synthesis
chemical_list: D011621:Pteridines; D011622:Pterins; D013763:Tetrahydrofolates; C012324:10-formylfolic acid; D018698:Glutamic Acid; C030371:5,6,7,8-tetrahydrofolic acid; C005926:2-amino-4-hydroxy-6-formylpteridine; D005492:Folic Acid; D003903:Deuterium; D002955:Leucovorin; D010129:4-Aminobenzoic Acid; C005984:5-methyltetrahydrofolate