Antiplasmodial Oleanane Triterpenoids from Root Bark.

Phytochemical investigation of the -BuOH extract of the roots of Sc. Elliot (Combretaceae) led to the isolation and identification of 10 oleanane triterpenoids (-), among which six new compounds, i.e., albidanoside A (), albidic acid A (), albidinolic acid (), albidienic acid (), albidolic acid (), and albidiolic acid (), and two triterpenoid aglycones, i.e., albidic acid B () and albidic acid C (), were isolated here for the first time from a natural source, along with two known compounds. The structures of these constituents were established by means of 1D and 2D NMR spectroscopy and ESI mass spectrometry. The isolated compounds were evaluated for their antiplasmodial and antimicrobial activity against the chloroquine-resistant strain K1, , and . Compounds -, , , and showed moderate antiplasmodial activity with IC values between 5 and 15 μM. None of the tested compounds were active against or . These findings emphasize the potential of as a source for discovery of new antiplasmodial compounds.