STUDIES ON THE ANTITUMOR CONSTITUENTS OF CEPHALOTAXUS HAINANENSIS LI.

ABSTRACT Eleven alkaloids were isolated from the bark of Cephalotaxus hainanensis Li. Nine of them were identified as deoxyharringtonine(Ⅰ),isoharringtonine(Ⅱ), harringtonine(Ⅲ),homoharringtonine(Ⅳ),cephalotaxine(Ⅴ),drupacine(Ⅵ), desmethylcephalotaxinone(Ⅶ),3-epischelhammericine(Ⅷ)and epicephalotaxine (Ⅺ),respectively.The structure of alkaloid Ⅸ,a new alkaloid,was postulated on the bases of its spectrometric data as the epimer of“phelline alkaloid 6”.Alkaloid X has not yet been characterized due to scarcity of material. Alkaloids Ⅰ,Ⅱ,Ⅲ and Ⅳ increased the life span in the L 615 lymphocytic leukemic mice,while alkaloids Ⅴ,Ⅵ,Ⅶ and Ⅹ were inactive.Alkaloids Ⅰ,Ⅱ,Ⅲ and Ⅳ have been put under clinical trials and preliminary results indicate that alkaloid Ⅲ is effective in the treatment of both acute and chronic myelocytic leukemia.