Efficient Stereo-Selective Fluorination on Vitamin D3 Side-Chain Using Electrophilic Fluorination
Fumihiro Kawagoe1, Sayuri Mototani1, Atsushi Kittaka1
1Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1 Kaga, Itabashi, Tokyo 173-8605, Japan.
Biomolecules
|January 23, 2024
Summary
Researchers developed a new stereo-selective fluorination method for vitamin D3 side-chains. This efficient technique uses N-fluorobenzenesulfonimide and chiral auxiliaries for targeted C24 and C22 fluorination.
Area of Science:
- Organic Chemistry
- Medicinal Chemistry
- Fluorine Chemistry
Background:
- Vitamin D3 analogues are crucial in various biological processes.
- Developing novel synthetic routes for modified vitamin D3 is essential for drug discovery.
- Stereoselective fluorination offers precise control over molecular structure and biological activity.
Purpose of the Study:
- To introduce a novel electrophilic fluorination method for vitamin D3 side-chains.
- To achieve stereo-selective fluorination at the C24 and C22 positions.
- To explore the utility of N-fluorobenzenesulfonimide (NFSI) in this context.
Main Methods:
- Utilized N-fluorobenzenesulfonimide (NFSI) as the electrophilic fluorinating agent.
- Employed CD-ring imides with Evans chiral auxiliaries (compounds 26, 27, 30) to direct stereoselectivity.
- Applied these reagents to the side-chain of vitamin D3 analogues.
Main Results:
- Successfully developed a new stereo-selective fluorination methodology.
- Achieved targeted fluorination at the C24 and C22 positions of the vitamin D3 side-chain.
- Demonstrated the effectiveness of the chosen reagents and chiral auxiliaries.
Conclusions:
- The developed method provides an efficient route to side-chain fluorinated vitamin D3 analogues.
- This stereoselective approach enhances the synthesis of complex vitamin D3 derivatives.
- The findings contribute to the broader field of synthetic organic and medicinal chemistry.
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