A biomimetic method to synthesise indolo[3,2- a ]carbazoles

A simple and biomimetic synthetic strategy for indolo[3,2-a]carbazoles has been developed. Our approach involved the efficient conversion of 2-(3′-indolyl)tryptophan derivatives into the corresponding α-keto esters and the subsequent aromatic cyclisation of these intermediates to construct the characteristic heteroaryl-condensed carbazole core.