Synthesis of cystine-peptide by a new disulphide bond-forming reaction using the siiyl chloride–sulphoxide system

Abstract

Methyltrichlorosilane or tetrachlorosilane in trifluoroacetic acid, in the presence of diphenylsulphoxide, is found to cleave various S-protecting groups of cysteine to form cystine directly by the reduction–oxidation reaction; this new disulphide bond forming reaction is successfully applied to the syntheses of oxytocin and human brain natriuretic peptide.