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Published on: June 13, 2022
A concise formal synthesis of (-)-hamigeran B
Biao Jiang1, Ming-Ming Li, Ping Xing
1CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China. jiangb@sioc.ac.cn
Organic Letters
|February 6, 2013
Summary
Researchers report a concise synthesis of (-)-hamigeran B, a complex natural product. Key steps include a Pauson-Khand reaction and Suzuki coupling, achieving high stereoselectivity for efficient drug discovery.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Natural Product Synthesis
Background:
- (-)-hamigeran B is a complex natural product with potential biological activities.
- Efficient synthetic routes are crucial for accessing and studying such molecules.
Purpose of the Study:
- To develop a concise and efficient formal synthesis of (-)-hamigeran B.
- To establish a scalable route for potential pharmaceutical applications.
Main Methods:
- The synthesis commenced with 3-methoxy-5-methylphenyl trifluoromethanesulfonate.
- Key reactions included an intermolecular Pauson-Khand reaction and a Claisen rearrangement for chiral quaternary carbon construction (>99% ee).
- Cyclohexane ring B was formed via aldehyde Friedel-Crafts cyclization, and ring C was completed using Suzuki coupling.
Main Results:
- An 11-step synthesis route was established with a 7.2% overall yield.
- High stereoselectivity (>99% ee) was achieved in constructing the chiral quaternary center.
- The synthesis successfully introduced the isopropenyl group of ring C.
Conclusions:
- The reported synthesis is concise and efficient, providing a viable route to (-)-hamigeran B.
- The methodology demonstrates the utility of Pauson-Khand and Suzuki coupling reactions in complex molecule synthesis.
- This work facilitates further investigation into the biological properties of (-)-hamigeran B.
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