Skip to Content
Merck
  • A simple preparation of the methotrexate metabolites 7-hydroxymethotrexate and 4-deoxy-4-amino-N10-methylpteroic acid.

A simple preparation of the methotrexate metabolites 7-hydroxymethotrexate and 4-deoxy-4-amino-N10-methylpteroic acid.

Therapeutic drug monitoring (1983-01-01)
D A Cairnes, W E Evans
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.

MATERIALS
Product Number
Brand
Product Description

Methotrexate impurity E, European Pharmacopoeia (EP) Reference Standard
Pricing and availability is not currently available.