Dimeric antioxidant and cytotoxic triterpenoid saponins from Terminalia ivorensis A. Chev.

Three saponins, including two dimeric triterpenoid glucosides possessing an unusual skeleton (1, 2) and a monomeric triterpenoid saponin (3) together with the known sericoside, were isolated from the bark of Terminalia ivorensis. These compounds were evaluated for their antioxidant properties and further for their cytotoxic activity against two human cancer cell lines. Compounds 2 and 3 exhibited scavenging activity against DPPH and ABTS+ radicals with IC50 values comparable with that of Trolox. Compound 1 showed antiproliferative activity against MDA-MB-231 and HCT116 human cancer cell lines with IC50 values of 3.96 and 3.43 μM, respectively.