Synthesis and biological evaluation of bengacarboline derivatives.

Novel derivatives of the marine alkaloid bengacarboline have been synthesized. The seco derivatives 11 and 12 were evaluated for topoisomerase inhibition, DNA damages, cytotoxicity and cell cycle perturbation. The two synthetic analogs are more potent cytotoxic agents than bengacarboline and they both induce an accumulation of cells in the S phase of DNA synthesis. They do not function as topoisomerase inhibitors but trigger DNA damages in cells.