Lignans and terpenoids from Gaultheria leucocarpa var. yunnanensis and their anti-inflammatory and antioxidant activities

Six new compounds, including three lignans (1a, 1b, and 2), two abietane-type diterpenoids (3 and 4), and a triterpenoid (5), together with 13 known compounds (6a, 6b, and 7-17) were isolated from the aerial parts of Gaultheria leucocarpa var. yunnanensis. Their structures were elucidated by analysis of spectroscopic data involving NMR, IR, UV, and HRESIMS. The absolute configurations of lignans were confirmed by experimental and calculated ECD spectra. The anti-inflammatory and antioxidant activities of the isolates were evaluated. Compounds 12, 13, and 15 showed inhibitory effects against the LPS-induced production of NO in BV-2 microglial cells with the IC50 values of 30.50, 23.26, and 13.02 μM, respectively. In addition, compounds 2 and 7 performed moderate DPPH radical scavenging activities.