title: The phenacyl group as an efficient thiol protecting group in a peptide condensation reaction by the thioester method.
abstract: One of the condensation methods for the preparation of long-chain peptides, the so-called thioester method requires protecting groups for amino and thiol groups for regioselective ligation. In this study, we demonstrated that the phenacyl (Pac) group acts as an efficient protecting group of cysteine side chains. We synthesized a cysteine derivative carrying the Pac group at the side chain sulfur atom, and Pac-containing peptides and peptide thioesters were synthesized using it by the ordinary 9-fluorenylmethoxycarbonyl (Fmoc)-based solid-phase peptide synthesis strategy. Pac-containing peptide segments could be condensed by the thioester method. After the condensation reaction, Pac groups could be removed by Zn/AcOH treatment. In addition, the azido group, which was used for the protection of lysine side chains, was simultaneously converted into an amino group, demonstrating that this protecting group scheme simplified the deprotecting reaction after the peptide condensation reaction to a single step.
authors.affiliation: Department of Applied Biochemistry, School of Engineering, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan. katay@tokai-u.jp
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Katayama
authors.forename: Hironobu
authors.initials: H
authors.lastname: Hojo
mesh_terms: D000595:Amino Acid Sequence; D023181:Antimicrobial Cationic Peptides / Q000138:chemical synthesis / Q000737:chemistry; D003545:Cysteine / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000138:chemical synthesis / Q000737:chemistry; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D010456:Peptides, Cyclic / Q000138:chemical synthesis / Q000737:chemistry; D060327:Solid-Phase Synthesis Techniques / Q000379:methods*; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D023181:Antimicrobial Cationic Peptides; D004268:DNA-Binding Proteins; D010455:Peptides; D010456:Peptides, Cyclic; D013438:Sulfhydryl Compounds; C057636:tachyplesin peptide, Tachypleus tridentatus; D003545:Cysteine