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Building photoswitchable 3,4'-AMPB peptides: Probing chemical ligation methods with reducible azobenzene thioesters.

ABSTRACT: Photoswitchable peptides were synthesized by using cysteine- and auxiliary-based native chemical ligation reactions. For this purpose, the two regioisomeric azobenzene building blocks 3,4'-AMPB thioester 1b and 4,4'-AMPB thioester 2b were employed in the ligation reactions. While 4,4'-AMPB requires the 4,5,6-trimethoxy-2-mercaptobenzyl auxiliary to minimize reduction of the diazene unit, 3,4'-AMPB can be used in combination with the 4,5,6-trimethoxy-2-mercaptobenzyl auxiliary as well as the N(?)-2-mercaptoethyl auxiliary. Thus, 3,4'-AMPB derivatives/peptides proved to be significantly less prone to reduction by aliphatic and aromatic thiols than were the 4,4'-AMPB compounds.

SUBMITTER: Zeyat G

PROVIDER: S-EPMC3388879 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Building photoswitchable 3,4'-AMPB peptides: Probing chemical ligation methods with reducible azobenzene thioesters.

Zeyat Gehad G Rück-Braun Karola K

Beilstein journal of organic chemistry 20120618

Photoswitchable peptides were synthesized by using cysteine- and auxiliary-based native chemical ligation reactions. For this purpose, the two regioisomeric azobenzene building blocks 3,4'-AMPB thioester 1b and 4,4'-AMPB thioester 2b were employed in the ligation reactions. While 4,4'-AMPB requires the 4,5,6-trimethoxy-2-mercaptobenzyl auxiliary to minimize reduction of the diazene unit, 3,4'-AMPB can be used in combination with the 4,5,6-trimethoxy-2-mercaptobenzyl auxiliary as well as the N(α) ...[more]

PMID: 23015839

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