https://www.mpegs-1.com/index.php/2016/07/28/the-nmr-screening-carried-out-on-foldamers-with-various-secondary-constructions-resulted-in-that-a-h14-helix-created-with-2aminocyclohexanecarboxylic-acid-achc-residues-and-ionizable-b3-amino-acids/