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Disulfide-Bridged Peptides That Mediate Enantioselective Cycloadditions through Thiyl Radical Catalysis.

ABSTRACT: An enantioselective vinylcyclopropane ring-opening/cycloaddition cascade is described. The active thiyl radical catalysts are generated in situ via UV light-promoted homolysis of cystine-based dimers. Amide-functionalization of the peptide at the 4-proline position is essential for effective asymmetric induction. Stereochemical communication is dependent on steric interactions with this substituent that are enforced by H-bonding to the peptide backbone.

SUBMITTER: Ryss JM

PROVIDER: S-EPMC5963541 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Disulfide-Bridged Peptides That Mediate Enantioselective Cycloadditions through Thiyl Radical Catalysis.

Ryss Jonathan M JM Turek Amanda K AK Miller Scott J SJ

Organic letters 20180305 6

An enantioselective vinylcyclopropane ring-opening/cycloaddition cascade is described. The active thiyl radical catalysts are generated in situ via UV light-promoted homolysis of cystine-based dimers. Amide-functionalization of the peptide at the 4-proline position is essential for effective asymmetric induction. Stereochemical communication is dependent on steric interactions with this substituent that are enforced by H-bonding to the peptide backbone. ...[more]

PMID: 29504763

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