2,2 '-bispyridyl disulfide rapidly induces intramolecular disulfide bonds in peptides

A linear peptide containing two reduced cysteine residues can be rapidly co nverted to its oxidized cyclic form containing an intramolecular disulfide bond by adding an excess of 2,2'-bispyridyl disulfide (2,2'-dipyridyl disul fide or 2,2'-dithiodipyridine) to conventional buffer solutions. The reacta nts and products are easily separated by reverse-phase chromatography. This reaction will find wide application in forming intramolecular disulfide bo nds because of its selectivity for free sulfhydryl groups, quickness, safet y, and applicability under acidic conditions. (C) 1999 Elsevier Science Inc . All rights reserved.