Novel approach to biscarbazole alkaloids via Ullmann coupling--synthesis of murrastifoline-A and bismurrayafoline-A.

@article{Brger2012NovelAT,
  title={Novel approach to biscarbazole alkaloids via Ullmann coupling--synthesis of murrastifoline-A and bismurrayafoline-A.},
  author={Carsten B{\"o}rger and Olga N. Kataeva and Hans‐Joachim Kn{\"o}lker},
  journal={Organic \& biomolecular chemistry},
  year={2012},
  volume={10 36},
  pages={
          7269-73
        }
}
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). 
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TLDR
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Iodine-catalyzed aromatization of tetrahydrocarbazoles and its utility in the synthesis of glycozoline and murrayafoline A: a combined experimental and computational investigation.
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