Two new antimalarial quassinoid derivatives from the stems of Brucea javanica

Phytochemical investigation of the stems from Brucea javanica led to the isolation of two new quassinoids, brujavanol C (1) and brujavanol D (2), together with six known compounds (3-8). The chemical structures were elucidated by means of various spectroscopic methods. All the isolated compounds were evaluated for antimalarial activity against Plasmodium falciparum and compounds 6 and 7 exhibited the most potent activity against the K1 strain, with IC_{50} values of 1.41 and 1.06 μM, respectively.