Sesquiterpenes fromRhododendron nivaleand Their Anti‐Inflammatory Activity

Abstract

Two new germacrane sesquiterpenes, named nivalenoids A and B (1 and 2), along with four known sesquiterpenes (3–6), were isolated from the Rhododendron nivale. The structures of compounds 1 and 2 were elucidated by integrating spectroscopic analyses, including NMR, UV, IR, as well as HR‐MS data. Anti‐inflammatory activity by inhibiting lipopolysaccharide (LPS)‐induced NO production in RAW 264.7 cells revealed that compared with the positive control dexamethasone (IC50=2.50 μM), compounds 1 and 2 showed mild anti‐inflammatory activity, with IC50 value of 27.55 μM and 53.26 μM, respectively.