Novel approach to biscarbazole alkaloidsvia Ullmann coupling – synthesis of murrastifoline-A and bismurrayafoline-A

Abstract

Unprecedented Ullmann couplings of murrayafoline-A with either 6-bromo- or 4-bromocarbazole derivatives provide highly efficient synthetic routes to the biscarbazole alkaloids murrastifoline-A (6 steps, 66% overall yield) and bismurrayafoline-A (6 steps, 28% overall yield).