The invention relates to a process for introducing a thiol group a to a carbonyl group in a side chain of a protected a-amino acid, said protected a-amino acid having protecting groups on both the α-amine group and the a-carboxyl group. The process comprises a) if the side chain contains a functional group comprising a heteroatom bearing a hydrogen atom, protecting said functional group; b) treating the protected amino acid with a base of sufficient strength to abstract a hydrogen atom a to the carbonyl group, so as to form an anion; c) treating the anion with a reagent of structure Pr-S-L in which L is a leaving group and Pr is a thiol-protecting group, so as to introduce a Pr-S- group a to the carbonyl group; and d) converting the Pr-S- group to an H-S-(thiol) group. This process may be used to prepare ligated peptides.
One-Pot Peptide Ligation–Desulfurization at Glutamate
作者:Katie M. Cergol、Robert E. Thompson、Lara R. Malins、Peter Turner、Richard J. Payne
DOI:10.1021/ol403288n
日期:2014.1.3
steps from protected glutamic acid and could be incorporated at the N-terminus of peptides. The application of these peptides in one-pot ligation–desulfurization chemistry is demonstrated with a range of peptide thioesters, and the utility of this methodology is highlighted through the synthesis of the osteoporosis peptide drug teriparatide (Forteo).