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Updated: Jun 2, 2026

Solid Phase Synthesis of a Functionalized Bis-Peptide Using "Safety Catch" Methodology
Published on: May 15, 2012
N-methyl-phenacyloxycarbamidomethyl (Pocam) group: a novel thiol protecting group for solid-phase peptide synthesis
Hidekazu Katayama1, Yoshiaki Nakahara, Hironobu Hojo
1Department of Applied Biochemistry, Faculty of Engineering, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan. katay@tokai-u.jp
Abstract:
In the so-called thioester method for the condensation of peptide segments, protecting groups for amino and thiol groups are required for chemoselective ligation. In this study, we developed a novel thiol protecting group, N-methyl-phenacyloxycarbamidomethyl (Pocam). We used it for protection of cysteine side chains, and synthesized Pocam-containing peptides and peptide thioesters. These were condensed by the thioester method. After the condensation reaction, Pocam groups were cleaved by Zn/AcOH treatment. At the same time, the azido group, which was used for the protection of lysine side chains, was also converted to an amino group, demonstrating that this protecting group strategy simplified the deprotecting reaction after the peptide condensation reaction to only one step.
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