Tetrahydrohomopteroic acid

It is evident, therefore, that the 2,4-diaminopyrimidines, like pyrimethamine and trimethoprim, the dihydrotriazines like proguanil (in its active metabolite form), the 2,4-diaminopteridines, and methotrexate, inhibit dihydrofolate reductase. Their selective toxicity to plasmodia may be due to a combination of greater binding to the parasite enzyme and to their selective uptake by parasitised erythrocytes. However, a new antifolic mode of action has recently been proposed for compounds like tetrahydrohomopteroic acid [288], which may inhibit folate metabolism by an action on the feedback... 

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