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Total Synthesis of (-) and (+)-Zingibergingerols A
Manoj N Shet1,2, Chepuri V Ramana1,2
1Division of Organic Chemistry, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411 008, India.
The Journal of Organic Chemistry
|October 30, 2024
Summary
Researchers achieved the first total synthesis of Zingibergingerol A enantiomers. A novel gold-catalyzed cycloisomerization strategy was employed to construct the unique trioxabicyclo[4.2.1]nonane core structure.
Area of Science:
- Organic Chemistry
- Natural Product Synthesis
Background:
- Zingibergingerol A is a natural product with a complex polycyclic structure.
- Previous synthetic routes to Zingibergingerol A have been limited or incomplete.
Purpose of the Study:
- To achieve the first total synthesis of both enantiomers of Zingibergingerol A.
- To develop a novel synthetic strategy for constructing the 3,7,9-trioxabicyclo[4.2.1]nonane core.
Main Methods:
- Sequential C-C bond formations utilizing epichlorohydrin as a key building block.
- Gold-catalyzed alkynol cycloisomerization for the construction of the bicyclic core.
- Stereoselective installation of functional groups including epoxides and hydroxyls.
Main Results:
- Successful synthesis of both enantiomers of Zingibergingerol A.
- Demonstration of a novel gold-catalyzed cycloisomerization for constructing the target skeleton.
- Establishment of a convergent synthetic route with control over stereochemistry.
Conclusions:
- The developed synthetic strategy provides efficient access to Zingibergingerol A enantiomers.
- This work expands the synthetic toolbox for complex natural product synthesis.
- The methodology is applicable to the synthesis of related compounds with similar structural motifs.
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