PROTECTION OF THE CARBOXY GROUP IN THE FORM OF THE 2-CYANOETHYL ESTERS IN SYNTHESIS OF PEPTIDES
With the aim of studying the suitability of the 2-cyano group for the protection of carboxylic functions in peptide synthesis, we have obtained the 2-cyanoethyl esters of a number of amino acids and have studied their behavior under the conditions of peptide synthesis.The synthesis of the pentapeptide leucine-enkephalin has been performed with the use of 2-cyanoethyl protection for C-terminal carboxy groups throughout.The physicochemical characteristics of the compounds synthesized are given.