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Direct 11CN-Labeling of Unprotected Peptides via Palladium-Mediated Sequential Cross-Coupling Reactions.

ABSTRACT: A practical procedure for 11CN-labeling of unprotected peptides has been developed. The method was shown to be highly chemoselective for cysteine over other potentially nucleophilic residues, and the radiolabeled products were synthesized and purified in less than 15 min. Appropriate for biomedical applications, the method could be used on an extremely small scale (20 nmol) with a high radiochemical yield. The success of the protocol stems from the use of a Pd-reagent based on a dihaloarene, which enables direct "nucleophile-nucleophile" coupling of the peptide and [11C]cyanide by temporal separation of nucleophile addition.

SUBMITTER: Zhao W

PROVIDER: S-EPMC5572217 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Direct 11CN-Labeling of Unprotected Peptides via Palladium-Mediated Sequential Cross-Coupling Reactions.

Zhao Wenjun W Lee Hong Geun HG Buchwald Stephen L SL Hooker Jacob M JM

Journal of the American Chemical Society 20170517 21

A practical procedure for 11CN-labeling of unprotected peptides has been developed. The method was shown to be highly chemoselective for cysteine over other potentially nucleophilic residues, and the radiolabeled products were synthesized and purified in less than 15 min. Appropriate for biomedical applications, the method could be used on an extremely small scale (20 nmol) with a high radiochemical yield. The success of the protocol stems from the use of a Pd-reagent based on a dihal ...[more]

PMID: 28502164

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