Synthesis of optically pure Clausenamine-A and its demethoxylated analogs

The first total synthesis of Clansenamine-A (3) was developed involving the Suzuki cross-coupling and oxidative coupling reaction. The synthesis of its demethoxylated analogs 1 and 2 were also reported. Resolution of(+)-1, (+)-2, (+)-3 and (-)-1, (-)-2, (-)-3 were performed via their corresponding camphorsulfonates of the racemates. The absolute configurations of(+)-1, (+)-2, (+)-3 and (-)-1, (-)-2, (-)-3 were assigned as (aR) and (aS), respectively, by X-ray analysis and their CD spectrum. The primarily cytotoxic activities of these biscarbazoles against Plasmodium falciparum were briefly described. (C) 2000 Elsevier Science Ltd. All rights reserved.