Bioactive abietane diterpenes and benzofuran neolignans from the resins of Toxicodendron vernicifluum.

Six new compounds (1-6), including two abietane diterpenes (1,2) and four benzofuran neolignans (3-6), along with five known compounds (7-11) were isolated and identified through phytochemical investigation on the resins of Toxicodendron vernicifluum (Toxicodendri Resina). The structures of the new compounds were fully elucidated by their 1D and 2D NMR, HRESIMS, UV, and IR spectroscopic data analyses. The absolute configurations of 1-4 were deduced by comparison of the experimental and calculated electronic circular dichroism (ECD) data. The inhibitory effects of the isolates on myocardial fibrosis induced by TGF-β were examined, and compounds 1, 5, and 7-10 showed the anti-proliferation of myocardial fibroblasts at the concentrations of 10-40 μM in a dose-dependent manner.