Synthesis of the benzo[b] carbazoloquinone with the structure proposed for prekinamycin

Article abstract of DOI:10.1016/S0040-4039(00)60664-0

The synthesis of the N-cyano benzo[b]carbazolequinone with the structure proposed for prekinamycin has been achieved by palladium and copper catalyzed coupling of a 2-bromonaphthoquinone with an arylstannane followed by ring closure, N-cyanation, and demethylation. Unexpectedly, the ring closure reaction gave also a regioisomer by an unprecedented rearrangement reaction.