Aminopterin

A white to yellow powder; commonly used as the dihydrate which forms clustersof yellow needles;

Antineoplastic, antirheumatic, folic acid antagonist

Used in the production of anti- neurogranin antibodies.

A folic acid antagonist. Its actively transported into cells by thefolate transporter. In the cell, its converted to a high molecular weight polyglutamate metabolite by folylpolyglutamate synthase, that, in turn, binds to dihydrofolate reductase and inhibits its activity.