OxyFile #219

[Hydrogen peroxide for disulfide bridge formation in the 
synthesis of peptides with the sequence of the immunodominant 
epitope of HIV gp41 glycoprotein]

Author:  Sidorova MV; Kudriavtseva EV; Antopol'skii ML; 
         Pal'keeva ME; Ovchinnikov MV; Bespalova ZhD

Source:  Bioorg Khim 1996 Apr; 22(4):273-9


A simple, rapid, and highly efficient method for intramolecular 
disulfide formation in tryptophan-containing peptides using 
hydrogen peroxide was elaborated. Solid phase synthesis 
of the peptide fragment corresponding to 601-617 sequence 
of transmembrane gp41 glycoprotein of HIV-1 was performed 
by Fmoc-technique. Coupling of Fmoc-Asn-OH by DCC-HOBt 
method was shown to be accompanied by a side reaction of 
dehydration of asparagine amide function with the formation 
of side product (22%) containing 3-cyanoalanine residue. 
This side reaction was not observed, when Fmoc-Asn-OH was 
coupled in the form of its p-nitrophenyl ester and with 
HOBt as a catalyst.