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Updated: Jul 2, 2026
09:04
A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
Synthesis of (-)-hamigeran B
Douglass F Taber1, Weiwei Tian
1Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA. taberdf@udel.edu
The Journal of Organic Chemistry
|September 6, 2008
Summary
Researchers achieved the synthesis of (-)-hamigeran B using a novel rhodium-catalyzed C-H insertion method for cyclopentane construction. This approach efficiently installed key structural features, including the endo-isopropyl group.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Catalysis
Background:
- (-)-hamigeran B is a natural product with a complex polycyclic structure.
- Efficient synthetic routes to complex natural products are crucial for chemical synthesis and drug discovery.
Purpose of the Study:
- To develop a novel and efficient synthetic strategy for (-)-hamigeran B.
- To establish a new method for cyclopentane ring construction via rhodium-mediated C-H insertion.
Main Methods:
- Rhodium-catalyzed intramolecular C-H insertion of alpha-aryl-alpha-diazoketones for cyclopentane core formation.
- Selective hydrogenation of a cyclopropylidene substituent to install the endo-isopropyl group.
Main Results:
- Successful total synthesis of (-)-hamigeran B.
- Demonstration of a new rhodium-mediated C-H insertion reaction for constructing substituted cyclopentanes.
- Efficient installation of the sterically demanding endo-isopropyl group.
Conclusions:
- The developed synthetic route provides an effective pathway to (-)-hamigeran B.
- The rhodium-mediated C-H insertion offers a powerful new tool for cyclopentane synthesis.
- This methodology can be applied to the synthesis of other complex molecules.
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