An Enzymatic Platform for Aniline Synthesis Through Oxidative Amination
Xiang Zhao1,2, Zhen Liu2,3
1College of Life Sciences, Beijing Normal University, Beijing, 100875, China.
Angewandte Chemie (International Ed. in English)
|April 7, 2025
Summary
Researchers developed a biocatalytic platform for synthesizing anilines using engineered flavin-dependent enzymes. This novel method expands biocatalysis beyond P450s, enabling efficient production of diverse aniline compounds for organic synthesis.
Area of Science:
- Biocatalysis
- Organic Synthesis
- Enzyme Engineering
Background:
- Aniline motifs are prevalent in natural and synthetic molecules.
- Current C(sp2)-N bond formation methods are limited, with biocatalysis mainly relying on P450 enzymes.
- A need exists for broader biocatalytic approaches to aniline synthesis.
Purpose of the Study:
- To establish a novel biocatalytic platform for aniline synthesis.
- To engineer flavin-dependent enzymes for efficient oxidative amination of cyclohexanones.
- To broaden the scope of biocatalytic aniline production.
Main Methods:
- Directed evolution of the flavin-dependent enzyme, Pyrococcus abyssi oxidoreductase (PtOYE).
- Screening of evolved variants (e.g., OYE_G3, OYE_M3) for catalytic activity.
- Mechanistic studies to understand enzyme performance and byproduct formation.
Main Results:
- Identification of engineered PtOYE variants with broad substrate activity.
- Successful synthesis of 40 diverse secondary and tertiary anilines.
- Achieved up to 91% gas chromatography (GC) conversion.
- Enhanced imine desaturation kinetics and reduced phenol byproduct formation.
Conclusions:
- The developed enzymatic platform offers a powerful new tool for aniline synthesis.
- Flavin-dependent enzymes demonstrate significant potential in organic synthesis and drug discovery.
- This work expands the biocatalytic toolbox beyond traditional P450 systems.
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