Hofmann Degradation of Asparagine and Glutamine as an Efficient Approach for the Synthesis of Derivatized Lysine Homologs

Abstract

We present a convenient and efficient approach for synthesizing lysine homologs via the Hofmann rearrangement of N ‐protected L ‐asparagine and L ‐glutamine. This method enabled the preparation of a diverse family of noncanonical amino acids (ncAAs) bearing side chains with varied properties, including electron‐donating and electron‐accepting abilities, redox activity, and fluorescence. The luminescence properties and redox behavior of these ncAAs were investigated. Furthermore, the newly synthesized Fmoc‐protected ncAAs were successfully incorporated into a hexapeptide sequence using solid‐phase peptide synthesis, thus expanding the library of hexapeptide hydrogelators.