Solid-phase synthesis of "mixed" peptidomimetics using Fmoc-protected aza-/β3-amino acids and α-amino acids

A solid-phase fluorenylmethyloxycarbonyl (Fmoc)-based synthesis strategy is described for "mixed" aza-beta(3)-peptides as well as a convenient general approach for their required building blocks, the aza-beta(3)-amino acid residues (aza-beta(3)-aa). These monomers allow the synthesis of relatively large quantities of pure mixed aza-beta(3)-peptides. The required Fmoc-substituted aza-beta(3)-amino acids are accessible by convenient synthesis, and a number of monomers including those containing side chains with functional groups have been synthesized. The method was applied toward the solid-phase synthesis of aza-beta(3)-peptide mimetics of a biologically active histone H4 sequence.