Syntheses and biological activities of bis(3-indolyl)thiazoles, analogues of marine bis(indole)alkaloid nortopsentins

The thiazole analogues of the marine bis(indole)alkaloid nortopsentins, 2,4-bis(3-indolyl)thiazoles, were synthesized using Hantzsch reaction between indole-3-thioamides and 3-(α-bromoacetyl)indoles as the key step, and these analogues showed potent cytotoxic activities against a variety of human cancer cell lines in vitro.