METHOD FOR SYNTHESIZING PEPTIDES

The present invention relates to a novel method for synthesizing peptides in solution, the method comprising: a) treating a peptide or amino acid derivative, which has an alpha-amine function blocked with a urethane group of the formula R -SO2-CH2CH2-O-CO-, wherein R is aryl, with an excess of an aliphatic secondary amine in an organic solvent to provide the release of the free alpha-amine function of said amino acid or peptide derivative and the formation of a tertiary amine adduct between said secondary amine and the liberated vinyl compound of the formula R -SO2-CH2=CH2; b) removing the solvent and the excess of said secondary amine; c) contacting thus formed mixture of the Nalpha-deprotected amino acid or peptide derivative and said tertiary amine adduct with subsequent peptide or amino acid derivative Nalpha-protected with the above indicated or another urethane group under conditions providing the formation of a peptide bond between the free alpha-amine function of the Nalpha-deprotected amino acid or peptide derivative and an alpha-carboxylic function of the subsequent Nalpha-protected peptide or amino acid derivative; d) separating the newly formed peptide from the reaction mixture; e) repeating procedures as set forth above until the desired polypeptide is obtained.