A new nor-eudesmane-type sesquiterpene from Fissistigma polyanthum

Twelve compounds were isolated and purified from Fissistigma polyanthum by using various modern separation techniques such as silica gel, MCI, ODS, and Sephadex LH-20 column chromatography, as well as preparative HPLC. The structures of these compounds were determined by spectroscopic methods and identified as fissistigmaoid A (1), (10S)-11-hydroxy-β-cyperone (2), 11-hydroxy-8-oxo-β-cyperone (3), (4S, 5E, 10R)-7-oxo-tri-nor-eudesm-5-en-4β-ol (4), oxyphyllanene B (5), teuhetone (6), teuhetenone A (7), trans-4, 5-dihydroxycorocalane (8), 4-hydroxy-4, 7-dimethyl-1-tetralone (9), epicatechin (10), dihydroquercetin (11), and piperolactam C (12). Among them, compound 1 is a new nor-eudesmane-type sesquiterpene, while compounds 1-9 were isolated from F. polyanthum for the first time. Compounds 8 and 12 exhibited NO inhibitory activity in an LPS-induced RAW 264.7 murine macrophage inflammation model, with IC₅₀ values of 30.5 ± 1.5 and 10.5 ± 1.0 μmol·L^-1 respectively.