Synthesis of selenium-containing biindolyls and their Diels-Alder reaction toward the synthesis of heteroannulated [a]- and [c]-carbazoles

We reported the first syntheses of 2- and 3-(2-(benzo[b]selenophen-2-yl)-indoles and their Diels-Alder reactions to furnish six unique annulated benzoselenphene carbazoles. This facile route can be used to synthesize selenium-containing biindolyl derivatives that possessed potential pharmaceutical activities.