Heterospirocyclic 3-Amino-2H-azirines as Convenient Building Blocks in Peptide Synthesis

Abstract

Heterospirocyclic 3-amino-2H-azirines with a tetrahydropyran (Thp), tetrahydrothiopyran (Tht), or N-protected piperidine (Pip) moiety are useful reagents for the preparation of peptides containing the corresponding six-membered heterocyclic 4-amino-4-carboxylic acid unit. In the present study, tripeptides of the type H-Asp-D-Ala-Xaa-OMe, where Xaa is the heterocyclic amino acid, were prepared according to the ‘azirine/oxazolone method’.