Peptide synthesis: synthesis of the cysteine-containing peptides of biological and pharmaceutical interest, α-h-ANF and h-big endothelin

Abstract
The biologically important vasoactive peptides, α-h-atrial natriuretic factor (ANF) and h-Big endothelin (Big ET) have been synthesised using the solid-phase Fmoc strategy with reference to the choice of protecting group for cysteine residues. Selective disulfide bond formation was seen to be problematical in the synthesis of Big ET but use of the acetamidomethyl (Acm) group, removal with the silver ions and oxidation using the mixed disulfide method proved successful.