N→S acyl-transfer-mediated synthesis of peptide thioesters utilizing an N-aminoacyl-N-sulfanylethylaminobenzoic acid derivative has been examined. The developed synthetic methodology for peptide thioesters is compatible with Fmoc solid-phase peptidesynthesis (SPPS).
absence of phosphate salts to afford ligated products, whereas soluble SEAlide peptides do not. This unexpected difference in reactivity of the SEAlide peptides allows for a one-pot/three-fragment ligation using resin-bound and unbound peptides.
A facile procedure has been developed for the synthesis of C-terminal peptide thioacids under mild conditions. A series of N-sulfanylethylanilide peptides prepared using Fmoc-based solid-phase peptide synthesis were successfully converted to the corresponding thioacids via a hydrothiolysis reaction in a phosphate buffer with only trace epimerization of the C-terminal amino acid. (C) 2015 Elsevier Ltd. All rights reserved.
Sequential native chemical ligation utilizing peptide thioacids derived from newly developed Fmoc-based synthetic method
The first facile Fmoc-based synthetic procedure for peptide thioacids was developed. Successful application of the resulting thioacids to sequential native chemical ligation (NCL) in the N to C direction was achieved. Conversion of the peptide thioacids to the corresponding thioesters with Ellman's reagent followed by NCL in the presence of tris(2-carboxyethyl)phosphine (TCEP) and thiophenol was accomplished in a one-pot manner. (C) 2010 Elsevier Ltd. All rights reserved.