Chemical synthesis of N-peptidyl 2-pyrrolidinemethanethiol for peptide ligation

Peptides carrying a C-terminal 2-pyrrolidinemethanethiol (PMT) unit were synthesized using 9-fluorenylmethoxycarbonyl (Fmoc) solid-phase peptide synthesis (SPPS), and were shown to ligate efficiently with cysteinyl-peptides. This novel PMT-mediated ligation tolerated many different C-terminal residues and was successfully applied to a one-pot N-to-C sequential ligation reaction and the semi-synthesis of lysine 16 acetylated histone H4, demonstrating the utility of the method in peptide and protein synthesis.