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Epimerization-free access to C-terminal cysteine peptide acids, carboxamides, secondary amides, and esters via complimentary strategies.

ABSTRACT: C-Terminal cysteine peptide acids are difficult to access without epimerization of the cysteine ?-stereocenter. Diversification of the C-terminus after solid-phase peptide synthesis poses an even greater challenge because of the proclivity of the cysteine ?-stereocenter to undergo deprotonation upon activation of the C-terminal carboxylic acid. We present herein two general strategies to access C-terminal cysteine peptide derivatives without detectable epimerization, diketopiperazine formation, or piperidinylalanine side products.

SUBMITTER: Arbour CA

PROVIDER: S-EPMC5868297 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Epimerization-free access to C-terminal cysteine peptide acids, carboxamides, secondary amides, and esters <i>via</i> complimentary strategies.

Arbour Christine A CA Kondasinghe Thilini D TD Saraha Hasina Y HY Vorlicek Teanna L TL Stockdill Jennifer L JL

Chemical science 20171109 2

C-Terminal cysteine peptide acids are difficult to access without epimerization of the cysteine α-stereocenter. Diversification of the C-terminus after solid-phase peptide synthesis poses an even greater challenge because of the proclivity of the cysteine α-stereocenter to undergo deprotonation upon activation of the C-terminal carboxylic acid. We present herein two general strategies to access C-terminal cysteine peptide derivatives without detectable epimerization, diketopiperazine formation, ...[more]

PMID: 29629104

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