Clavirolide G, a new rare dolabellane-type diterpenoid from the Xisha soft coral Clavularia viridis

Abstract One new dolabellane-type diterpenoid, named clavirolide G ( 1 ), and one known related analogue ( 3 ), have been isolated from the soft coral Clavularia viridis collected off the Xisha Islands in the South China Sea. Its structure and absolute configuration were determined on the basis of spectroscopic analysis, electronic circular dichroism, and compared with literature model compounds. The cytotoxic activity of these two compounds was evaluated against a panel of human tumor cell lines. Compound 1 showed moderate cytotoxic activity against KB and HL-60 cells.