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REVIEW
Contents Vol 68(4)

Synthetic Amino Acids for Applications in Peptide Ligation–Desulfurization Chemistry

Lara R. Malins A and Richard J. Payne A B
+ Author Affiliations
- Author Affiliations

A School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia.

B Corresponding author. Email: richard.payne@sydney.edu.au




Lara R. Malins completed her undergraduate studies in chemistry in 2009 as a Trustee Scholar at Boston University, where she worked in the laboratory of Associate Professor Scott Schaus on the synthesis of purine-based natural products. She was awarded an International Postgraduate Research Scholarship in 2010 to undertake her Ph.D. at the University of Sydney, Australia, in the group of Professor Richard Payne. She completed her doctorate in April 2014 and is currently a post-doctoral research associate in the Payne laboratory, focusing on the development of novel ligation methodologies for the synthesis of complex peptide and glycopeptide targets.


Richard J. Payne graduated from the University of Canterbury, New Zealand, in 2002. In 2003, he was awarded a Gates Scholarship to undertake his Ph.D. within the Department of Chemistry, University of Cambridge, under the supervision of Professor Chris Abell. After completing his Ph.D., Richard moved to the Scripps Research Institute under the auspices of a Lindemann Postdoctoral Fellowship where he worked in the laboratory of Professor Chi-Huey Wong. In 2008, he moved to the University of Sydney as a lecturer within the School of Chemistry, where he is currently Professor of Organic Chemistry and Chemical Biology and ARC Future Fellow. Richard's research focuses on utilising the tools of synthetic chemistry, including peptide and carbohydrate chemistry, to address problems of biochemical and medicinal significance.

Australian Journal of Chemistry 68(4) 521-537 https://doi.org/10.1071/CH14568
Submitted: 15 September 2014  Accepted: 9 October 2014   Published: 23 January 2015

Abstract

Native chemical ligation is a powerful tool for the convergent assembly of homogeneous peptide and protein targets from unprotected peptide fragments. The method involves the chemoselective coupling of a peptide thioester with a peptide bearing an N-terminal cysteine (Cys) residue and is mediated by the nucleophilic Cys thiol functionality. A widely adopted extension of the technique for the disconnection of protein targets at alanine (Ala) ligation junctions has been the application of post-ligation desulfurization protocols for the mild removal of the Cys thiol moiety. Recently, attention has turned to the construction of synthetic amino acid building blocks bearing suitably positioned β-, γ-, or δ-thiol ligation auxiliaries with a view to expanding the scope of the ligation–desulfurization manifold. To date, several thiol-derived amino acids have been prepared, greatly increasing the generality and flexibility of chemoselective ligation technologies for the chemical synthesis of diverse protein targets. This review will highlight the current synthetic approaches to these important amino acid building blocks.


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