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Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
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Total Synthesis of (-)-Arborisidine.
1Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing, 100084, China.
Angewandte Chemie (International Ed. in English)
|March 29, 2021
Summary
Researchers present an asymmetric total synthesis of the cage-like indole alkaloid arborisidine. This novel strategy utilizes catalytic kinetic resolution and radical cyclization to construct complex chiral centers and ring systems.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Natural Product Synthesis
Background:
- Indole alkaloids represent a significant class of natural products with diverse biological activities.
- Arborisidine is a complex, cage-like indole alkaloid whose total synthesis presents a considerable challenge.
- Establishing quaternary stereocenters is a common hurdle in the synthesis of complex natural products.
Purpose of the Study:
- To develop a novel and efficient asymmetric total synthesis of arborisidine.
- To establish a robust strategy for constructing the intricate cage-like structure of arborisidine.
- To control the absolute configurations of two quaternary chiral centers within the arborisidine framework.
Main Methods:
- Asymmetric total synthesis employing a catalytic parallel kinetic resolution.
- Utilizing the ambident nucleophilicity (C3/N) of indole to control stereochemistry.
- Employing a 5-exo-trig radical cyclization for the formation of a key bridged ring system.
Main Results:
- Successful asymmetric total synthesis of arborisidine.
- Precise control over the absolute configurations of two quaternary chiral centers was achieved.
- Efficient construction of the bridged nitrogen-containing five-membered ring via radical cyclization.
Conclusions:
- The presented synthetic strategy provides an effective route to arborisidine.
- The methodology highlights the power of catalytic kinetic resolution and radical cyclization in complex molecule synthesis.
- This work offers a valuable platform for accessing other structurally related indole alkaloids.
Keywords:
arborisidinepalladium catalysisparallel kinetic resolutionradical cyclizationtotal synthesisMore Related Videos
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