title: A simple preparation of the methotrexate metabolites 7-hydroxymethotrexate and 4-deoxy-4-amino-N10-methylpteroic acid.
abstract: Simple and convenient preparations of two metabolites of the antineoplastic drug methotrexate (MTX) are described. MTX is incubated in a Tris-HCl rabbit liver homogenate to produce 7-hydroxymethotrexate. Filtration, lyophilization, and recrystallization from water gives a chromatographically pure product. Analytical amounts of 4-deoxy-4-amino-N10-methylpteroic acid (DAMPA) are prepared by 0.05 N NaOH hydrolysis of an amide bond within the MTX molecule. Preparative high-performance liquid chromatography was used for purification of DAMPA. Nominal molecular weights of these metabolites have been confirmed by fast atom bombardment mass spectrometry. These synthetic methods provide a simple and efficient source of these compounds for use as standards in analytical methods, drug metabolism and cytotoxicity studies, and therapeutic drug monitoring.
mesh_terms: D000818:Animals; D001711:Biotransformation; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism; D013058:Mass Spectrometry; D008727:Methotrexate / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism*; D011817:Rabbits
chemical_list: C000203:deoxyaminopteroic acid; C011864:7-hydroxymethotrexate; D008727:Methotrexate