title: Human urinary metabolites of 1-(tetrahydro-2-furanyl)-5-fluorouracil (ftoraful).
abstract: Two hydroxylated metabolites were isolated from the urine of a patient who had received ftorafur (5 g/sq m). These metabolites were identified by mass spectrometry and nuclear magnetic resonance spectroscopy as trans-3'- and cis-4'-hydroxyftorafur. The compounds were not converted to 4-fluorouracil when incubated in plasma, base (pH 9), or water. Because of their stability, it is unlikely that these metabolites are in vivo precursors of 5-fluorouracil. There are indications that less stable, unisolatable, hydroxylated ftorafur derivatives are intermediates in the conversion of ftorafur to 5-fluorouracil.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D005472:Fluorouracil / Q000031:analogs & derivatives*; D006801:Humans; D006900:Hydroxylation; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D005641:Tegafur / Q000031:analogs & derivatives / Q000652:urine*
chemical_list: D005641:Tegafur; D005472:Fluorouracil