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The availability of stable, short-helical peptides would provide useful frameworks for the design of biologically active small molecules as well as models for probing aspects of protein folding. Several approaches have recently been reported for stabilizing «-helical peptides including incorporation of salt bridges, 1 metal chelates, 2 or amide bonds3 that bridge the i and i+ 4 positions; incorporation of amino acids with high helix propensity4 and helix caps; 5 and the formation of amphiphilic helix bundles. 6 7One of the most successful strategies to date exploits the disulfide-bridged framework of the bee venom peptide, apamin, to generate chimeric «-helical peptides. 7 We now report the synthesis of short peptides containing a two-turn «-helix stabilized by a single intramolecular disulfide bond bridging the i and i+ 7 residues (Scheme I). An eight-residue peptide containing this bridge shows high helicity in water at 0 …