In the course of the screening of plants from Niger for antiprotozoal activity, the methanol extract ofCassia sieberiana, and the dichloromethane extracts ofZiziphus mauritianaandSesamun alatumwere found to be active against protozoan parasites, namelyTrypanosoma brucei rhodesiense,Trypanosoma cruzi,Leishmania donovaniand/orPlasmodium falciparum. Myricitrin (1), quercitrin (2) and 1-palmitoyl-lysolecithin (3) were isolated fromC. sieberiana. FromZ. mauritiana, the three triterpene derivatives13,15, and16are described here for the first time. Their chemical structures were determined by 1D and 2D NMR experiments, UV, IR and HRESIMS data. The absolute configurations were assigned via comparison of the experimental and calculated ECD spectra. In addition, eight known cyclopeptide alkaloids (4,5,7–12), and five known triterpenoids (6,14,17–19) were isolated. The antiprotozoal activity of the isolated compounds, as well as of eleven quinone derivatives (20–30) previously isolated fromS. alatumwas determinedin vitro.The cytotoxicity in L6 rat myoblast cells was also evaluated. Compound18showed the highest antiplasmodial activity (IC50= 0.2 µm) and compound24inhibitedT. b. rhodesiensewith an IC50value of 0.007µM. However, it also displayed significant cytotoxicity in L6 cells (IC50= 0.4 µm).