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Biocatalytic Asymmetric Cyclopropanations via Enzyme-Bound Iminium Ion Intermediates.

ABSTRACT: Cyclopropane rings are an important structural motif frequently found in many natural products and pharmaceuticals. Commonly, biocatalytic methodologies for the asymmetric synthesis of cyclopropanes rely on repurposed or artificial heme enzymes. Here, we engineered an unusual cofactor-independent cyclopropanation enzyme based on a promiscuous tautomerase for the enantioselective synthesis of various cyclopropanes via the nucleophilic addition of diethyl 2-chloromalonate to α,β-unsaturated aldehydes. The engineered enzyme promotes formation of the two new carbon-carbon bonds with excellent stereocontrol over both stereocenters, affording the desired cyclopropanes with high diastereo- and enantiopurity (d.r. up to 25:1; e.r. up to 99:1). Our results highlight the usefulness of promiscuous enzymes for expanding the biocatalytic repertoire for non-natural reactions.

SUBMITTER: Kunzendorf A

PROVIDER: S-EPMC8596749 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Biocatalytic Asymmetric Cyclopropanations via Enzyme-Bound Iminium Ion Intermediates.

Kunzendorf Andreas A Xu Guangcai G Saifuddin Mohammad M Saravanan Thangavelu T Poelarends Gerrit J GJ

Angewandte Chemie (International ed. in English) 20211005 45

Cyclopropane rings are an important structural motif frequently found in many natural products and pharmaceuticals. Commonly, biocatalytic methodologies for the asymmetric synthesis of cyclopropanes rely on repurposed or artificial heme enzymes. Here, we engineered an unusual cofactor-independent cyclopropanation enzyme based on a promiscuous tautomerase for the enantioselective synthesis of various cyclopropanes via the nucleophilic addition of diethyl 2-chloromalonate to α,β-unsaturated aldehy ...[more]

PMID: 34490955

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