Synthesis and conformational studies of a hybrid cyclic peptide based on cis-beta-furanoid sugar amino acid (FSAA) and ornithine

The conformational control of a 14-helix nucleating template, cis-beta-furanoid sugar amino acid (FSAA), over a flexible delta-amino acid, ornithine is studied in a FSAA-ornithine cyclic tetrapeptide. Extensive NMR and MD studies reveal that the cyclic peptide adopts a three-dimentional bowl-shape cavity, which promotes six- and seven-membered intra- and inter-residue H-bonding, in polar and non-polar solvents, respectively.