Folding control of a non-natural glycopeptide using saccharide-coded structural information for polypeptides.

We synthesized "glyco-arylopeptides", whose folding structure significantly changes depending on the kind of saccharide in their side chain. The saccharide moiety interacts with the main chain via hydrogen bonding, and the non-natural polypeptides form two well-defined architectures-(P)-3- and (M)-4-helices-depending on the length of the saccharide chains and even the configuration of a single stereo-genic center in the epimers.