Cadinane sesquiterpenes from the stems and branches of Illicium ternstroemioides

Three new cadinane sesquiterpenes (1–3) and three known sesquiterpenes were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith. The structures of the new compounds were elucidated by extensive analysis of spectroscopic and HRESIMS data. The structures of illiternins A–C (1–3) were confirmed by single crystal X-ray diffraction, allowing for the determination of their absolute configurations. Compounds 3 and 6 exhibited antiviral activity against Coxsackievirus B3 with IC₅₀ values of 33.3 and 57.7 μM, respectively.