Sesquiterpenoids from the Roots of Aucklandia Costus And Their Anti-Inflammatory Activities

Abstract

Five undescribed sesquiterpenoid dimers, aucklandiolides A–E (1–5), one new sesquiterpenoid glycoside, β-cyclocostunolide-15-β-D-glycoside (6), and seventeen known analogues (7–23) were isolated from the roots of Aucklandia costus. Their structures were elucidated by comprehensive HRESIMS, NMR, and ECD spectroscopic data analysis. Aucklandiolides A and B are the first examples of dimeric sesquiterpenoids with a unique 6/6/6/5/6/6 ring system originated from a proposed Diels–Alder cycloaddition between two eudesmane sesquiterpenoids. Besides, compounds 9–11, 20, and 22 showed significant inhibition of nitric oxide production in LPS-stimulated RAW 264.7 cells at a concentration of 20 μM.

Keywords: Aucklandia costus, Sesquiterpenoid dimer, Aucklandiolide A, Nitric oxide