Secobutanolides Isolated from Lindera obtusiloba Stem and Their Anti-Inflammatory Activity

In this study, a new secobutanolide, named secosubamolide B (<b>3</b>), along with three previously known secobutanolides (<b>1</b>, <b>2</b>, and <b>4</b>), were successfully isolated from a methanol extract of the stem of <i>Lindera obtusiloba</i>. The chemical structures of these compounds were elucidated through the analysis of spectroscopic data, and then compared with the existing literature to confirm their identities. Furthermore, the anti-inflammatory effect of these isolated compounds on bone marrow-derived dendritic cells stimulated by lipopolysaccharide (LPS) was evaluated. Compounds <b>1</b>-<b>3</b> showed the significant suppression of LPS-triggered IL-6 and IL-12 p40 production, with IC₅₀ values between 1.8 and 24.1 µM. These findings may provide a scientific foundation for developing anti-inflammatory agents from <i>L. obtusiloba</i>.