title: Studies on trypsin inhibitors. Part III. Synthesis of the protected decapeptide (sequence 15-24) of porcine pancreatic secretory trypsin inhibitor II (Kazal).
abstract: The synthesis of the amino-protected decapeptide tert-butyloxycarbonylhydrazide corresponding to positions 15-24 of the amino acid sequence of porcine pancreatic secretory trypsin inhibitor II (Kazal inhibitor) is described. The tripeptide free base threonyl-beta-tert-butylaspartylglycine tert-butyloxycarbonylhydrazide (sequence 22-24) was acylated with 1-succinimidyl o-nitrophenylsulfenylvalyl-S-acetamidomethylcysteinylglycinate (sequence 19-21). Removal of the amino protecting group from the resulting hexapeptide followed by acylation of the free base with either benzyloxycarbonylisoleucyl-O-tert-butyltyrosylasparaginylproline or O-nitrophenylsulfenylisoleucyl-O-tert-butyltyrosylasparaginylproline, via the pyrazoline active ester method, yielded the decapeptide tert-butyloxycarbonylhydrazide (sequence 15-24) in the form of Nalpha-benzyloxycarbonyl or Nalpha-O-nitrophenylsulfenyl derivative. The stereochemical homogeneity of the two decapeptides was assessed, after partial deprotection with liquid hydrogen fluoride, or thioacetamide and aqueous 90% trifluoroacetic acid, by digestion with papain and aminopeptidase M followed by quantitative amino acid analysis.
mesh_terms: D000818:Animals; D001216:Asparagine; D001224:Aspartic Acid; D003545:Cysteine; D005998:Glycine; D007532:Isoleucine; D010455:Peptides / Q000032:analysis / Q000138:chemical synthesis*; D011392:Proline; D013552:Swine; D013912:Threonine; D014359:Trypsin Inhibitor, Kazal Pancreatic / Q000032:analysis / Q000138:chemical synthesis*; D014361:Trypsin Inhibitors / Q000138:chemical synthesis*; D014443:Tyrosine; D014633:Valine
chemical_list: D010455:Peptides; D014361:Trypsin Inhibitors; D007532:Isoleucine; D013912:Threonine; D001224:Aspartic Acid; D014443:Tyrosine; D014359:Trypsin Inhibitor, Kazal Pancreatic; D001216:Asparagine; D011392:Proline; D014633:Valine; D003545:Cysteine; D005998:Glycine