Convenient synthesis of human calcitonin and its methionine sulfoxide derivative

The human calcitonin peptide chain was assembled using Fmoc solid-phase peptide synthesis chemistry. The combinations of cleavage Reagent H with trans-[Pt(en)2Cl2]2+ and Reagents B, K, and R with trans-[Pt(CN)4Cl2]2− provide convenient methods for the synthesis of human calcitonin and its methionine sulfoxide derivative; the formation of intramolecular disulfide bonds by the above Pt(IV) oxidants is essentially quantitative.