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Stereodivergent atom-transfer radical cyclization by engineered cytochromes P450
Qi Zhou1, Michael Chin1, Yue Fu2
1Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
Science (New York, N.Y.)
|December 23, 2021
Summary
Researchers engineered metalloenzymes, like cytochromes P450, to control stereochemistry in free-radical reactions. This breakthrough enables precise asymmetric catalysis, offering a powerful new tool for synthesizing complex molecules.
Area of Science:
- Biocatalysis and synthetic chemistry.
- Enzyme engineering and directed evolution.
- Asymmetric catalysis and radical reactions.
Background:
- Enzymes offer unique reactivity for biocatalyst development.
- Controlling stereochemistry in free-radical reactions is challenging in synthetic chemistry.
- First-row transition metals inspire redox enzyme design.
Purpose of the Study:
- To repurpose cytochromes P450 for stereoselective atom-transfer radical cyclization.
- To engineer metalloenzymes for precise stereocontrol in radical catalysis.
- To develop an evolvable platform for asymmetric radical reactions.
Main Methods:
- Directed evolution of cytochromes P450.
- Engineering metalloenzymes for radical cyclization.
- Investigating stereocontrol in radical addition and halogen rebound steps.
Main Results:
- Engineered metalloenzymes achieved substantial stereocontrol in radical processes.
- Demonstrated enantio- and diastereodivergent asymmetric catalysis.
- Successfully repurposed P450 enzymes for unnatural radical reactions.
Conclusions:
- Evolvable metalloenzymes provide a novel solution for controlling radical intermediates.
- This platform enables precise stereochemistry in asymmetric radical catalysis.
- Repurposed enzymes offer a powerful approach to challenging synthetic transformations.
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