Triterpenoid Saponins From the Root Bark of Haplocoelum congolanum

Two undescribed triterpenoid saponins together with 5 known ones were isolated from the root bark of Haplocoelum congolanum Hauman. Their structures were elucidated by spectroscopic methods including one-dimensional and two-dimensional nuclear magnetic resonance experiments in combination with mass spectrometry as 3-O-(4-O-[3-hydroxy-3-methylglutaryl])–l-arabinopyranosyl-(13)–l-rha mnopyranosyl-(12)-[-d-glucopyranosyl-(14)]–l-arabinopyranosyloleanoli c acid and 3-O–l-arabinofuranosyl-(13)–l-rhamnopyranosyl-(12)-[-d-glucopyranosy l-(14)]–l-arabinopyranosyloleanolic acid.