SYNTHESIS OF EDATREXATE (2-C-13-GLUTAMATE)

The experimental antitumor drug Edatrexate, labeled with 99% C-13 at t he 2-position of the glutamate acid group was required for C-13-magnet ic resonance spectroscopy studies in biological media. Coupling of 2,4 -diamino-4-deoxy-10-ethyl-10-deazapteroic acid with diethyl L-2-C-13-g lutamate as promoted by BOP reagent afforded Edatrexate (2-C-13-glu) d iethyl ester in 60% yield following purification by column chromatogra phy. Saponification by aqueous NaOH in 2-methoxyethanol gave the targe t molecule in 44% yield or 26% overall.