Reactivity of dehydroaspartic acid derivatives under peptide coupling conditions

✍ Scribed by Nalin L Subasinghe; Rodney L. Johnson

• Book ID: 104215736
• Publisher: Elsevier Science
• Year: 1992
• Tongue: French
• Weight: 293 KB
• Volume: 33
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)79048-4

✦ Synopsis

The reactivity of a-car~ctivated &h#roaspartic acid derivadves with various N-and 0-nuckophiles is described for the first time. Reaction of amino acid derivatives with AC-AZAsp(OBu')-OH (da) under a variety of coupling conditions gave very poor yields of rhe resuliing deh@oaspartyl dipepddes, while the coupling qf4a with oxygen nucleophiles gave very good y'elds of the dehydroaqmrtyl esters. In contrast. du cowling of amino acids with

Cbs-AzAsp(OBut)-OH (4b) gave good yields of dehydroaspartyl dipeptides. The fomuation of a highly reactive

oxazolone intemzediate is proposed to explain the low yieldc of pepdde coupling behvecn da and amino aci&.