Antiprotozoal activity of synthetic amino substituted 1-methyl-1H-α-carbolines

The antiprotozoal properties of a series of amino substituted 1-methyl-1H-α-carbolines were investigated in a broad panel of parasites. Various substituents were systematically introduced at various positions on the carbocyclic ring of the parent 1-methyl-1H-α-carboline. Most compounds showed a potent antiprotozoal activity, although mostly accompanied by cytotoxicity on MRC-5 cells. One compound, containing the same amino-substitution as chloroquine, showed an IC50 against Plasmodium falciparum of 2.37 M and was reasonably selective.