Derivatives of amino-acids and peptides V. Complex formation of benzyloxycarbonylamino-acids with their salts

✍ Scribed by E. P. Grommers; J. F. Arens

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 387 KB
• Volume: 78
• Category: Article
• ISSN: 0165-0513
• DOI: 10.1002/recl.19590780802

✦ Synopsis

Abstract

Benzyloxycarbonylamino‐acids and ‐peptides very easily form addition compounds with their alkali metal salts; this sometimes causes difficulties during the preparation of benzyloxycarbonylamino‐acids or ‐peptides. The complexes may separate in crystalline form when aqueous solutions of the salts are acidified; they can also be prepared by mixing solutions of the free benzyloxycarbonyl derivatives with solutions of appropriate amounts of the salts. Some complexes are oily and fairly soluble in ethyl acetate. From one set of components (Cbo‐amino‐acid and its salt) sometimes more than one type of complex can be obtained each having a characteristic melting point. The solvent used for the crystallisation largely defines the complex. Within one type the salt content can vary. It seems that within certain limits an arbitrary number of metal ions can replace protons of COOH groups.