Modified method of synthesis of N-substituted dithioesters of amino acids and peptides in the Pinner reaction

An improved method for the synthesis of dithioesters of amino acids and peptides has been developed. The syntheses have been carried out from the nitriles. The addition of thiol to the nitrile derivative in the Pinner step of dithioester synthesis was activated with hydrogen fluoride. A few examples of dithioester synthesis using liquid HF are described. Some novel dithioesters, which are model compounds for resonance Raman spectroscopic studies of dithioacylpapain intermediates, are described. Key words: dithioesters, amino acids, Pinner reaction, HF, isotopes.