Tri‐Orthogonal Scaffolds for the Solid‐Phase Synthesis of Peptides

Abstract

Multi‐orthogonal scaffolds can be useful for the attachment of several different compounds to the same central skeleton. Such compounds can find applications in the development of protein mimics because of their potential to mimic several distant epitopes in the protein structure. Three new tri‐orthogonal variants of a previously reported scaffold have been developed that are suitable for the solid‐phase synthesis of three different peptides on the same skeleton. Different chemical moieties were combined for the phased attachment of amino acids to the scaffolds: Fmoc‐ or Alloc‐protected amine, free or TIPS‐protected alkyne or azido group. Several model compounds were prepared, characterized, and compared for their suitability as new scaffolds for peptide synthesis. All three scaffolds provided peptides with satisfactory yields and purities, making them suitable for a synthesis of libraries of compounds.