Soluble α-amino acid salts in acetonitrile:: Practical technology for the production of some dipeptides

[GRAPHICS] alpha-Amino acids are soluble in acetonitrile when treated with phosphazene bases. As a result, the protection/deprotection events that are usually required for peptide coupling reactions can be minimized. This is illustrated in the synthesis of the important angiotensin-converting enzyme (ACE) inhibitor enalapril.