Thiol capture ligation

D.S. Kemp, R.I. Carey, Synthesis of a 39-peptide and a 25-peptide by thiol-capture ligations observation of... 

Kemp s thiol capture ligation demonstrates that amide bond formation, even between large peptide segments with only moderate activation, can be rapid... 

Template-mediated ligation, an approach to bring two peptide fragments into close proximity. The N-terminus of one peptide and C-terminus of the other peptide are attached to a template, and consequently close to each other so that they can form a peptide bond. The basic principle was created by Brenner et al. using a salicylamide template based on a base-catalyzed intramolecular rearrangement and has been later exploited in thiol capture ligation [M. Bretmer et al., Helv. Chim. Acta 1957, 40, 1497]. 

Thiol capture ligation, a variant of template-mediated ligation used for amide bond formation between two unprotected peptide fragments. According to Kemp, a 4-hydroxy-6-mercaptodibenzofuran template with a hydroxy and a thiol substituent has been employed. One peptide is connected with its C-terminus to the hydroxyl substituent, while the other peptide containing an N-terminal Cys residue is connected to the template thiol across a disulfide bond. This brings the N-terminus of one peptide and C-terminus of the other peptide into close proximity, and the amide bondforming step occurs as a very rapid in-... 

Schnolzer and Kent, 1992), oxime-fonning ligation (Rose, 1994) and thiol capture method (Liu and Tam, 1994) and activated amide ligation (Saxon et al, 2000). 

Kemp DS, Buckler DR (1991) Highly enantioselective amide ligation by prior thiol capture. Tetrahedron Lett 32 3013-3016... 

The protonated nature of the Nt-cysteinyl thiol Inhibits thloester ligation but permits imine capture of the Ct-glycoaldehyde ester and it s tautomerization to a stable thiazolidine ester 4. (Adapted from Tam et ah, 2001)... 

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