Abstract A wide variety of substituted p-sulfamoylphenylazo compounds were prepared, and their activity against Plasmodium berghei in mice was studied. A study of the effects of substitution in the sulfamoyl group revealed that substitution by pyrimidine, methylpyrimidine, and hexylresorcinol greatly increased the antimalarial activity, while substitution by thiazole, methylthiazole, and 2-methyl-3, 4-thiadiazole did not lead to a ...