A novel solid phase approach to Aia-containing peptides.

A strategy was developed to directly assemble 4-amino-1,2,4,5-tetrahydro-indolo[2,3-c]-azepin-3-ones on solid-phase-supported peptide sequences. Fmoc- and Boc-based strategies were investigated. The Fmoc-strategy approach strongly depends on the peptide sequence being synthesized while the Boc-based synthesis leads to excellent results for all the selected peptide analogs. The method was applied to prepare Aia-analogs of several bioactive peptides containing one or more Trp-residues which were shown to be important for biological recognition.