Antischistosomal Tetrahydro-γ-carboline Sulfonamides

We discovered tetrahydro-γ-carboline sulfonamides as a new antischistosomal chemotype. The aryl sulfonamide and tetrahydro–γ–carboline substructures were required for high antischistosomal activity. Increasing polarity improved solubility and metabolic stability but decreased antischistosomal activity. We identified two compounds with IC(50) values < 5 μM against ex vivo Schistosoma mansoni.