title: @-Tide-stabilized beta-hairpins.
abstract: As minimalist versions of beta-structure, two-stranded beta-hairpins are commonly employed as platforms for assessing the interactions that stabilize beta-sheets in proteins. We have found that the presence of a 1,6-dihydro-3(2H)-pyridinone moiety (the "@-unit") as an amino acid replacement at the i - 1 or i + 4 positions relative to a beta-turn strongly stabilizes the hairpin conformation. Hybrids of this type bridge the gap between natural beta-hairpins and unnatural beta-sheets because the @-unit only replaces one residue in a peptide while stabilizing the hairpin conformation to a greater extent than a normal amino acid. In this report, we describe the synthesis of a variety of @-tide-templated hairpins and the NMR and CD characterization of their conformations in both polar and nonpolar solvents.
authors.affiliation: Center for New Directions in Organic Synthesis, Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
authors.forename: Scott T
authors.initials: ST
authors.lastname: Phillips
authors.forename: Landy K
authors.initials: LK
authors.lastname: Blasdel
authors.forename: Paul A
authors.initials: PA
authors.lastname: Bartlett
mesh_terms: D006860:Hydrogen Bonding; D046911:Macromolecular Substances / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D011728:Pyridones / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; D010455:Peptides; D011728:Pyridones