Trimetrexate is a quinazoline

Quinazoline

Quinazoline is a compound made up of two fused six-membered simple aromatic rings, a benzene ring and a pyrimidine ring. Its chemical formula is C8H6N2. Quinazoline is yellow and crystalline...

 derivative. It is a dihydrofolate reductase inhibitor

Dihydrofolate reductase inhibitor

A dihydrofolate reductase inhibitor is a molecule that inhibits the function of dihydrofolate reductase, and is a type of antifolate.Since folate is needed by rapidly dividing cells to make thymine, this effect may be used to therapeutic advantage. For example, methotrexate is used as cancer...

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Uses

It has been used with leucovorin in treating pneumocystis pneumonia

Pneumocystis pneumonia

Pneumocystis pneumonia or pneumocystosis is a form of pneumonia, caused by the yeast-like fungus Pneumocystis jirovecii...

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It has been investigated for use in treating leiomyosarcoma

Leiomyosarcoma

Leiomyosarcoma , aka LMS, is a malignant cancer of smooth muscle....

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It is a methotrexate (MTX) analog that is active against transport-deficient MTX-resistant tumor cells that overcome the acquired and natural resistance to methotrexate. Other uses include skin lymphoma.