title: Synthesis and structure of symmetrical bicyclic hexapeptides bridged by metathesis reaction.
abstract: [structure: see text] Bicyclic hexapeptides 1a-c were synthesized via an intramolecular ring-closing metathesis reaction on solid phase followed by an N- to C-terminal cyclization in solution. Structural elucidation showed that these compounds assumed a C2-symmetrical structure with two beta-turns. The trans-ethylene plane was found to occupy two positions in rapid interconversion. One of the bicyclic hexapeptides crystallized with five water molecules, which made an arch above the ethylene group.
authors.affiliation: LAPP, CNRS-UMR 5810, Universités de Montpellier I et II, 15 Avenue Charles Flahault, BP 14 491, 34093 Montpellier Cedex 5, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Giovannoni
authors.forename: Claude
authors.initials: C
authors.lastname: Didierjean
authors.forename: Philippe
authors.initials: P
authors.lastname: Durand
authors.forename: Michel
authors.initials: M
authors.lastname: Marraud
authors.forename: André
authors.initials: A
authors.lastname: Aubry
authors.forename: Patrice
authors.initials: P
authors.lastname: Renaut
authors.forename: Jean
authors.initials: J
authors.lastname: Martinez
authors.forename: Muriel
authors.initials: M
authors.lastname: Amblard
mesh_terms: D003500:Cyclization; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010456:Peptides, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry; D011487:Protein Conformation; D013237:Stereoisomerism
chemical_list: D010456:Peptides, Cyclic