Chemical Synthesis of Peptide-Thioesters for Native Chemical Ligation — ASN Events
  1. Schedule
  2. Opening Plenary Session
  3. Chemical Synthesis of Peptide-Thioesters for Native Chemical Ligation

Chemical Synthesis of Peptide-Thioesters for Native Chemical Ligation (#1)

Stephen Kent 1
  1. Department of Chemistry, University of Chicago, Chicago, USA

Synthetic peptide-thioesters are the key building blocks for total protein synthesis by modern native chemical ligation methods.[1] They can be prepared in straightforward fashion by “in situ neutralization” Boc chemistry solid phase peptide synthesis (SPPS).[2] Sparingly soluble peptide-thioesters can be rendered soluble by the use of (Arg)n tags in the thioester leaving group moiety.[3] Although “in situ neutralization” Boc chemistry SPPS is highly effective for the preparation of peptide-thioesters, the use of liquid HF in the final deprotection and cleavage step is a barrier to the use of this chemistry in many laboratories. We and others [4] are developing non-HF ‘on-resin flow deprotection/thiolysis’ methods to obviate the need to use HF in Boc chemistry SPPS for making peptide-thioesters. Efficient conversion of the product peptide-thioesters to free acids will be discussed.[5] Case studies in the preparation of peptide-thioesters and their use in chemical protein synthesis will be presented.

1. Total chemical synthesis of proteins. Stephen B.H. Kent, Chemical Society Reviews, 38, 338-51 (2009).

2. "In situ" neutralization protocols in Boc-chemistry solid phase peptide synthesis: rapid, high yield assembly of difficult sequences. Martina Schnölzer, Paul Alewood, Dianne Alewood, Stephen B.H. Kent, Int. J. Pept. Prot. Res., 40, 180-193 (1992); [Republished: International Journal of Peptide Research and Therapeutics, 13, 31–44 (2007)].

3. Towards the total chemical synthesis of integral membrane proteins:  a general method for the synthesis of hydrophobic peptide-athioester building blocks. Erik C.B. Johnson, Stephen B.H. Kent, Tetrahedron Letters, 48, 1795-99 (2007).

4. Chemical synthesis of an erythropoietin glycoform containing a complex-type disialyloligosaccharide. Masumi Murakami, Ryo Okamoto, Masayuki Izumi, Yasuhiro Kajihara, Angew. Chem., Int. Ed., 51, 3567-72 (2012).

5. Rapid formal hydrolysis of peptide-athioesters. Zachary P. Gates, Jules Stephan, Dong Jun Lee, Stephen B.H. Kent, Chem. Commun., 49, 786-788  (2013).