Synthesis of Methylene‐Bridged Biscarbazole Alkaloids by using an Ullmann‐type Coupling: First Total Synthesis of Murrastifoline‐C and Murrafoline‐E
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| Authors: | Sebastian K Kutz Dr Carsten Börger Dr Arndt W Schmidt Prof?Dr Hans‐Joachim Knölker |
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| Institution: | 1. Department Chemie, Technische Universit?t Dresden, Dresden, Germany), Fax;2. +49)351‐463‐37030 |
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| Abstract: | We describe the total synthesis of methylene‐bridged biscarbazole alkaloids by using a late‐stage Ullmann‐type coupling of fully functionalised carbazole subunits. The carbazole derivatives were synthesised via a sequence of palladium(0)‐ and palladium(II)‐catalysed coupling reactions. Our approach has provided bismurrayafoline‐A, bismurrayafolinol, chrestifolines B–D, and the first total synthesis of murrastifoline‐C and murrafoline‐E. |
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| Keywords: | alkaloids C− H bond activation copper cyclisation natural products palladium |
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