Synthesis of 12-epi-ent-polyalthenol an antitumour indole sesquiterpene alkaloid

Abstract The synthesis of 12- epi - ent -polyalthenol, 10 , and its epimer at C-19, 11 , from ent -halimic acid as starting material has been carried out. The structure of the natural product polyalthenol 1 is confirmed in this way. The synthesized indole sesquiterpenes 10 and 11 and their acetylderivatives 32 and 33 inhibited cellular proliferation of a number of human leukaemic and solid tumour cell lines.