Facile synthesis of benzamides to mimic an α-helix

A new α-helix mimetic was designed by using a benzamide as a rigid scaffold. It presents three functional groups corresponding to side chains of amino acids found at the i, i + 4, and i + 7 positions of an ideal α-helix, which are displayed on the same helical face. Its efficient synthesis was achieved by employing simple alkylation and amidation reactions which can be easily adapted for solid-phase synthesis. As a result, two tris-benzamides were produced to mimic two helical regions found in a peptide hormone, glucagon.