Azido acids in a novel method of solid-phase peptide synthesis

Article abstract of DOI:10.1016/S0040-4039(97)00393-6

Azido acids were produced from α-branched acids by α-bromination with NBS followed by substitution with sodium azide and the products were used in a novel method of solid-phase synthesis. The azido acids were transformed into the highly activated acid chlorides and used synthesis of extremely hindered peptides containing up to four successive diphenyl glycine or Aib residues. By reaction of the genetically encoded amino acids with TfN₃ and then SOCl₂ they were transformed into α-azido acid chlorides used in solid-phase peptide synthesis without racemization.