Columns: Polymer Supports in Synthesis

Abstract

The focus of this month's column is on a general protocol for the solid phase synthesis of azapeptides without racimization, using a polymer support, where the aza-amino acid residue is introduced as an N-Boc-aza-dipeptide. This development was recently reported by Melendez and Lubell at the University of Montreal (JACS, 2004, 126, 6759–64). However, before summarizing the synthetic pathway, azapeptides will be introduced.Azapetides are peptide analogs where the α-carbon of one or more of the amino acid residues has been replaced by a nitrogen atom. A normal dipeptide portion of a peptide is compared to an azapeptide in structures 1 and 2, respectively. Natural peptides are widely investigated as drugs, but they are frequently rapidly metabolized.