A new rearranged eudesmane sesquiterpene and bioactive sesquiterpenes from the twigs of Lindera glauca (Sieb. et Zucc.) Blume.

A new rearranged eudesmane sesquiterpene, named eudeglaucone (1), and five known sesquiterpenes including (+)-faurinone (2) and four eudesmane-type sesquiterpenes (3-6), were isolated from the twigs of Lindera glauca (Sieb. et Zucc.) Blume. The structure of 1 was elucidated by a combination of extensive spectroscopic analyses, including extensive 2D NMR (1H-1H COSY, HMQC, HMBC, and NOESY) and HR-MS. Compound 1 was a relatively rare rearranged eudesmane sesquiterpene in terpenoids. All isolates were evaluated for their antiproliferative activities against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15). Compounds 3 and 6 showed significant cytotoxicity against SK-MEL-2 and HCT-15 cell lines with IC50 values ranging from 9.98 to 12.20 μM. We also investigated the anti-neuroinflammatory activities of the isolates (1-6) in the lipopolysaccharide (LPS)-stimulated murine microglia BV-2 cell line by measuring nitric oxide (NO) levels. All isolates significantly inhibited NO production with IC50 values of 3.67-26.48 μM without inducing cell toxicity.