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

The conformational control of a 14-helix nucleating template, cis-β-furanoid sugar amino acid (FSAA), over a flexible δ-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

Total synthesis of azumamide E and sugar amino acid-containing analogue

An efficient and practical total synthesis of marine cyclic tetrapeptide, natural product azumamide E (1) is achieved via high-yielding reactions. The strategy also allowed us to synthesize the azumamide E-SAA (sugar amino acid) analogue (2), whose solution-phase NMR and biological activity studies were also carried out

β-Sugar aminoxy peptides as rigid secondary structural scaffolds

Short homo-oligomers of a new building block, cis-β2,3-furanoid sugar aminoxy acid, are designed, characterized, and found to exhibit rigid ribbon-like secondary structures composed of 5/7 bifurcated intramolecular hydrogen bonds