Our primary aim is the development of a coordinated set of new reagents for peptide synthesis, comprising new amide forming reagents, protective groups which can be removed under exceedingly mild conditions, and protective groups which can be used to achieve affinity isolation and solubilization. Primary approaches to amide formation include safety-catch activation and prior amine capture. Independently usable affinity isolation procedures or """"""""handles"""""""" are to be used to achieve isolation and purification of products from coupling reactions without recourse to chromatography or crystallization. Protective groups are sought which can be removed with special reagents under conditions close to physiological minimizing damage to peptide products. Our new approach to amide formation involves prior thiol capture of an N-terminal cysteine residue of a peptide fragment, followed by intramolecular acyl transfer. In its most efficient form this strategy minimizes the need for protective groups and is therefore ideally suited to semisynthesis. Syntheses and semisyntheses of bovine pancreatic trypsin inhibitor and a series of analogs are described.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37GM013453-25
Application #
3484151
Study Section
Bio-Organic and Natural Products Chemistry Study Section (BNP)
Project Start
1976-12-01
Project End
1992-06-30
Budget Start
1990-07-01
Budget End
1991-06-30
Support Year
25
Fiscal Year
1990
Total Cost
Indirect Cost
Name
Massachusetts Institute of Technology
Department
Type
Schools of Arts and Sciences
DUNS #
City
Cambridge
State
MA
Country
United States
Zip Code
02139
Moreau, Robert J; Schubert, Christian R; Nasr, Khaled A et al. (2009) Context-independent, temperature-dependent helical propensities for amino acid residues. J Am Chem Soc 131:13107-16
Nasr, Khaled A; Schubert, Christian R; Torok, Marianna et al. (2009) Helix-coil energetics for helix formers and breakers reflect context and temperature: mutants of helically robust, guest-sensitive homopeptide hosts. Biopolymers 91:311-20
Fotouhi, N; Kemp, D S (1993) Novel class of silicon-based protective groups for the side chain of tyrosine. Int J Pept Protein Res 41:153-61
Fotouhi, N; Bowen, B R; Kemp, D S (1992) Resolution of proline acylation problem for thiol capture strategy by use of a chloro-dibenzofuran template. Int J Pept Protein Res 40:141-7
Kemp, D S; Fotouhi, N; Boyd, J G et al. (1988) Practical preparation and deblocking conditions for N-alpha-(2-(p-biphenylyl)-2-propyloxycarbonyl)-amino acid (N-a-Bpoc-Xxx-OH) derivatives. Int J Pept Protein Res 31:359-72