A new ursane-type triterpene from the whole plants of Ainsliaea glabra Hemsl.

A comprehensive phytochemical investigation of the whole plant extract of Ainsliaea glabra Hemsl. led to the isolation of nine compounds, including a new ursane-type triterpene fatty acid ester named 3β-O-heptadecanoyl-urs-12-ene (1), along with eight known compounds (2-9). Their structures were elucidated based on extensive spectroscopic analysis, including 1D and 2D NMR and HR-ESI-MS, and comparison with the literature. Biological activity evaluation results revealed that compound 1 displayed the most potent tyrosinase inhibitory activity with an IC50 value of 16.7 μg/mL.