Synthesis and structure of symmetrical bicyclic hexapeptides bridged by metathesis reaction.
[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.
Giovannoni
Jérôme
J
LAPP, CNRS-UMR 5810, Universités de Montpellier I et II, 15 Avenue Charles Flahault, BP 14 491, 34093 Montpellier Cedex 5, France.
Didierjean
Claude
C
Durand
Philippe
P
Marraud
Michel
M
Aubry
André
A
Renaut
Patrice
P
Martinez
Jean
J
Amblard
Muriel
M
D003500:Cyclization; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010456:Peptides, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry; D011487:Protein Conformation; D013237:Stereoisomerism
D010456:Peptides, Cyclic