Indole-Terpenoids With Anti-inflammatory Activities From Penicillium sp. HFF16 Associated With the Rhizosphere Soil of Cynanchum bungei Decne

Four new indole-terpenoids (1–4) named encindolene A, 18-O-methyl-encindolene A, encindolene B, and encindolene C, as well as three known analogs (5–7), were isolated from the fungus Penicillium sp. HFF16 from the rhizosphere soil of Cynanchum bungei Decne. The structures of compounds including absolute configurations were elucidated by spectroscopic data and electronic circular dichroism (ECD) analysis. Anti-inflammatory activity evaluation revealed that compounds 1–7 inhibit the production of nitric oxide with IC50 values of 79.4, 49.7, 81.3, 40.2, 86.7, 90.1, and 54.4 μM, respectively, and decrease the levels of tumor necrosis factor-α, interleukin-6 contents in lipopolysaccharide-induced RAW264.7 macrophages.