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An Umpolung Approach for the Chemoselective Arylation of Selenocysteine in Unprotected Peptides.

ABSTRACT: Herein we report an umpolung strategy for the bioconjugation of selenocysteine in unprotected peptides. This mild and operationally simple approach takes advantage of the electrophilic character of an oxidized selenocysteine (Se-S bond) to react with a nucleophilic arylboronic acid to provide the arylated selenocysteine within hours. This reaction is amenable to a wide range of boronic acids with different biorelevant functional groups and is unique to selenocysteine. Experimental evidence indicates that under oxidative conditions the arylated derivatives are more stable than the corresponding alkylated selenocysteine.

SUBMITTER: Cohen DT

PROVIDER: S-EPMC4613869 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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An Umpolung Approach for the Chemoselective Arylation of Selenocysteine in Unprotected Peptides.

Cohen Daniel T DT Zhang Chi C Pentelute Bradley L BL Buchwald Stephen L SL

Journal of the American Chemical Society 20150730 31

Herein we report an umpolung strategy for the bioconjugation of selenocysteine in unprotected peptides. This mild and operationally simple approach takes advantage of the electrophilic character of an oxidized selenocysteine (Se-S bond) to react with a nucleophilic arylboronic acid to provide the arylated selenocysteine within hours. This reaction is amenable to a wide range of boronic acids with different biorelevant functional groups and is unique to selenocysteine. Experimental evidence indic ...[more]

PMID: 26225900

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