Antiprotozoal activity of natural products from Nigerien plants used in folk medicine.

In the course of the screening of plants from Niger for antiprotozoal activity, the methanol extract of , and the dichloromethane extracts of and were found to be active against protozoan parasites, namely , , and/or . Myricitrin (), quercitrin () and 1-palmitoyl-lysolecithin () were isolated from . From , the three triterpene derivatives , , and are 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 (, , -), and five known triterpenoids (, , ) were isolated. The antiprotozoal activity of the isolated compounds, as well as of eleven quinone derivatives () previously isolated from was determined The cytotoxicity in L6 rat myoblast cells was also evaluated. Compound showed the highest antiplasmodial activity (IC = 0.2 µm) and compound inhibited with an IC value of 0.007 M. However, it also displayed significant cytotoxicity in L6 cells (IC = 0.4 µm).