Four New Cadinane‐Type Sesquiterpenoids From the Roots of Fissistigma tientangense

ABSTRACT

Four new cadinane‐type sesquiterpenoids, named fisscadinanes A–D ( 1 – 4 ), together with four known biogenetically related cadinane‐type sesquiterpenoids ( 5 – 8 ) were isolated from the roots of Fissistigma tientangense . The structures of these sesquiterpenoids were determined by comprehensive spectroscopic analyses. Compound 1 is a 15‐norcadinane sesquiterpene containing one p ‐ π – π ‐system. Compounds 2 ‐ 4 are cadinane sesquiterpenes. The absolute configurations of compounds 1 – 4 were determined via ECD calculations. The inhibitory activities of fisscadinanes A–D against the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in mouse macrophage RAW 264.7 cells in vitro were evaluated. Compounds 1 and 7 exhibited significant inhibitory activities, possessing the IC ₅₀ values of 8.27 ± 0.09 and 14.66 ± 0.08 µM. The positive control, quercetin, displayed an inhibitory activity against NO production with an IC ₅₀ value of 14.87 ± 0.11 µM.