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Catalytic Modification of Dehydroalanine in Peptides and Proteins by Palladium-Mediated Cross-Coupling.

ABSTRACT: Dehydroalanine (Dha) is a remarkably versatile non-canonical amino acid often found in antimicrobial peptides. Herein, we present the catalytic modification of Dha by a palladium-mediated cross-coupling reaction. By using Pd(EDTA)(OAc)₂ as water-soluble catalyst, a variety of arylboronic acids was coupled to the dehydrated residues in proteins and peptides, such as Nisin. The cross-coupling reaction gave both the Heck product, in which the sp² -hybridisation of the α-carbon is retained, as well as the conjugated addition product. The reaction can be performed under mild aqueous conditions, which makes this method an attractive addition to the palette of bio-orthogonal catalytic methods.

SUBMITTER: de Bruijn AD

PROVIDER: S-EPMC6146911 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Catalytic Modification of Dehydroalanine in Peptides and Proteins by Palladium-Mediated Cross-Coupling.

de Bruijn A Dowine AD Roelfes Gerard G

Chemistry (Weinheim an der Bergstrasse, Germany) 20180718 48

Dehydroalanine (Dha) is a remarkably versatile non-canonical amino acid often found in antimicrobial peptides. Herein, we present the catalytic modification of Dha by a palladium-mediated cross-coupling reaction. By using Pd(EDTA)(OAc)2 as water-soluble catalyst, a variety of arylboronic acids was coupled to the dehydrated residues in proteins and peptides, such as Nisin. The cross-coupling reaction gave both the Heck product, in which the sp2 -hybridisation of the α-carbon ...[more]

PMID: 29923249

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