Synthesis of thienocarbazoles by reductive cyclization of 6-(2’- nitrophenyl)benzo[b]thiophenes

Abstract

Thienocarbazoles are bioisosters of anti-tumoural pyridocarbazoles, ellipticine and olivacine. Methylated thienocarbazoles 1 were synthesized by reductive cyclization of 6-(2'nitrophenyl) benzo[b]thiophenes 2, using triethylphosphite. Compounds 2 were obtained by palladium-catalyzed cross-coupling between 2-bromo or iodonitrobenzenes and 6-boronic esters of methylated benzo[b]thiophenes (communication presented at this meeting).