title: Selenocysteine-mediated backbone cyclization of unprotected peptides followed by alkylation, oxidative elimination or reduction of the selenol.
abstract: An unprotected 16 residue peptide containing a C-terminal thioester and an N-terminal selenocysteine residue efficiently cyclizes in the presence of thiophenol; subsequent reduction, elimination or alkylation of the selenol yields modified cyclic peptides with alanine, dehydroalanine or a non-natural amino acid at the site of ligation.
authors.affiliation: Laboratory of Organic Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland.
authors.forename: Richard
authors.initials: R
authors.lastname: Quaderer
authors.forename: Donald
authors.initials: D
authors.lastname: Hilvert
mesh_terms: D000478:Alkylation; D000595:Amino Acid Sequence; D003500:Cyclization; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010455:Peptides / Q000737:chemistry*; D018036:Selenium Compounds / Q000737:chemistry*; D017279:Selenocysteine / Q000737:chemistry*
chemical_list: D010455:Peptides; D018036:Selenium Compounds; C442270:selenol; D017279:Selenocysteine