Download MendeleyChemodivergent C(sp 3 )-H and C(sp 2 )-H Cyanomethylation Using Engineered Carbene Transferases.
Zhang, J., Maggiolo, A.O., Alfonzo, E., Mao, R., Porter, N.J., Abney, N., Arnold, F.H.(2023) Nat Catal 6: 152-160
- PubMed: 36875868
- DOI: https://doi.org/10.1038/s41929-022-00908-x
- Primary Citation of Related Structures:
8DSG - PubMed Abstract:
The ubiquity of C-H bonds presents an attractive opportunity to elaborate and build complexity in organic molecules. Methods for selective functionalization, however, often must differentiate among multiple chemically similar and, in some cases indistinguishable, C-H bonds. An advantage of enzymes is that they can be finely tuned using directed evolution to achieve control over divergent C-H functionalization pathways. Here, we demonstrate engineered enzymes that effect a new-to-nature C-H alkylation with unparalleled selectivity: two complementary carbene C-H transferases derived from a cytochrome P450 from Bacillus megaterium deliver an α -cyanocarbene into the α -amino C(sp 3 )-H bonds or the ortho -arene C(sp 2 )-H bonds of N -substituted arenes. These two transformations proceed via different mechanisms, yet only minimal changes to the protein scaffold (nine mutations, less than 2% of the sequence) were needed to adjust the enzyme's control over the site-selectivity of cyanomethylation. The X-ray crystal structure of the selective C(sp 3 )-H alkylase, P411-PFA, reveals an unprecedented helical disruption which alters the shape and electrostatics in the enzyme active site. Overall, this work demonstrates the advantages of enzymes as C-H functionalization catalysts for divergent molecular derivatization.
Organizational Affiliation:
Division of Chemistry and Chemical Engineering, California Institute of Technology; Pasadena, California, United States.
