Vieloplains A-G, seven new guaiane-type sesquiterpenoid dimers from Xylopia vielana

Abstract Seven new guaiane-type sesquiterpene dimers vieloplains A-G, connecting patterns through three different direct C C bonds compounds 1 – 5 (C-3 to C-3′, C-4 to C-1′), compound 6 (C-2 to C-3′, C-4 to C-2′) and compound 7 ( C-2 to C-1′ , C-4 to C-2′ ) were isolated from the roots of Xylopia vielana . Their absolute configurations were established by NOESY analysis, the Cu K α X-ray crystallographic the experiment circular dichroism (ECD) and the calculated ECD. Among them, only compound 6 showed a considerable cytotoxicity against DU145 cells with IC 50 values of 9.5 μM. Flow cytometry analysis confirmed that 6 caused death of DU145 cells via apoptosis induction.