Triterpenoids with α-glucosidase inhibitory activity and cytotoxic activity from the leaves of .

Ten pentacyclic triterpenoids including a new multiflorane triterpene acid, 2α,3β,23-trihydroxymultiflor-7-en-28-oic acid (1), and a new lupane triterpene monoglucoside named akebiaoside C (2), were obtained from the leaves of . Their structures were elucidated by extensive spectroscopic analysis, and they were all isolated from the leaves of for the first time. These compounds, except 4 and 5, showed α-glucosidase inhibitory activity much stronger than acarbose. Especially, 2, 3, 6, 8 and 10 displayed α-glucosidase inhibitory activity with IC values from 0.004 to 0.081 mM, which were close or even more potent than corosolic acid (IC 0.06 mM). Triterpenoids 1, 8 and 10 were further revealed to show moderate cytotoxic activity against human tumor A549, HeLa and HepG2 cell lines, with IC values ranging from 26.5 to 51.9 μM. Compound 9 selectively showed cytotoxicity toward HeLa and HepG2 cell lines, with IC values of 81.49 and 73.47 μM, respectively. These findings provided new data to support that the leaves of are a rich source in bioactive triterpenoids highly valuable to be developed for medicinal usage.