title: Conformational Effects through Hydrogen Bonding in a Constrained γ-Peptide Template: From Intraresidue Seven-Membered Rings to a Gel-Forming Sheet Structure.
abstract: A series of three short oligomers (di-, tri-, and tetramers) of cis-2-(aminomethyl)cyclobutane carboxylic acid, a γ-amino acid featuring a cyclobutane ring constraint, were prepared, and their conformational behavior was examined spectroscopically and by molecular modeling. In dilute solutions, these peptides showed a number of low-energy conformers, including ribbonlike structures pleated around a rarely observed series of intramolecular seven-membered hydrogen bonds. In more concentrated solutions, these interactions defer to an organized supramolecular assembly, leading to thermoreversible organogel formation notably for the tripeptide, which produced fibrillar xerogels. In the solid state, the dipeptide adopted a fully extended conformation featuring a one-dimensional network of intermolecularly H-bonded molecules stacked in an antiparallel sheet alignment. This work provides unique insight into the interplay between inter- and intramolecular H-bonded conformer topologies for the same peptide template.
authors.affiliation: CP3A Organic Synthesis Group and Services Communs, ICMMO, UMR 8182, CNRS, Université Paris Sud, Université Paris Saclay , Bât. 420, 15 rue Georges Clemenceau, 91405 Orsay cedex, France.|Inorganic and Organometallic Coordination Chemistry Laboratory and Laboratory for Medicinal Chemistry and Natural Products, Faculty of Sciences (I) & PRASE-EDST, Lebanese University , Hadath, Lebanon.
authors.forename: Hawraà
authors.initials: H
authors.lastname: Awada
authors.affiliation: CP3A Organic Synthesis Group and Services Communs, ICMMO, UMR 8182, CNRS, Université Paris Sud, Université Paris Saclay , Bât. 420, 15 rue Georges Clemenceau, 91405 Orsay cedex, France.
authors.forename: Claire M
authors.initials: CM
authors.lastname: Grison
authors.affiliation: CP3A Organic Synthesis Group and Services Communs, ICMMO, UMR 8182, CNRS, Université Paris Sud, Université Paris Saclay , Bât. 420, 15 rue Georges Clemenceau, 91405 Orsay cedex, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Charnay-Pouget
authors.affiliation: CP3A Organic Synthesis Group and Services Communs, ICMMO, UMR 8182, CNRS, Université Paris Sud, Université Paris Saclay , Bât. 420, 15 rue Georges Clemenceau, 91405 Orsay cedex, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Baltaze
authors.affiliation: CP3A Organic Synthesis Group and Services Communs, ICMMO, UMR 8182, CNRS, Université Paris Sud, Université Paris Saclay , Bât. 420, 15 rue Georges Clemenceau, 91405 Orsay cedex, France.
authors.forename: François
authors.initials: F
authors.lastname: Brisset
authors.affiliation: CP3A Organic Synthesis Group and Services Communs, ICMMO, UMR 8182, CNRS, Université Paris Sud, Université Paris Saclay , Bât. 420, 15 rue Georges Clemenceau, 91405 Orsay cedex, France.
authors.forename: Régis
authors.initials: R
authors.lastname: Guillot
authors.affiliation: CP3A Organic Synthesis Group and Services Communs, ICMMO, UMR 8182, CNRS, Université Paris Sud, Université Paris Saclay , Bât. 420, 15 rue Georges Clemenceau, 91405 Orsay cedex, France.|UFR Sciences Pharmaceutiques et Biologiques, Université Paris Descartes , 4 avenue de l'Observatoire, 75270 Paris cedex 06, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Robin
authors.affiliation: Inorganic and Organometallic Coordination Chemistry Laboratory and Laboratory for Medicinal Chemistry and Natural Products, Faculty of Sciences (I) & PRASE-EDST, Lebanese University , Hadath, Lebanon.
authors.forename: Ali
authors.initials: A
authors.lastname: Hachem
authors.affiliation: Inorganic and Organometallic Coordination Chemistry Laboratory and Laboratory for Medicinal Chemistry and Natural Products, Faculty of Sciences (I) & PRASE-EDST, Lebanese University , Hadath, Lebanon.
authors.forename: Nada
authors.initials: N
authors.lastname: Jaber
authors.affiliation: Inorganic and Organometallic Coordination Chemistry Laboratory and Laboratory for Medicinal Chemistry and Natural Products, Faculty of Sciences (I) & PRASE-EDST, Lebanese University , Hadath, Lebanon.
authors.forename: Daoud
authors.initials: D
authors.lastname: Naoufal
authors.affiliation: Inorganic and Organometallic Coordination Chemistry Laboratory and Laboratory for Medicinal Chemistry and Natural Products, Faculty of Sciences (I) & PRASE-EDST, Lebanese University , Hadath, Lebanon.
authors.forename: Ogaritte
authors.initials: O
authors.lastname: Yazbeck
authors.affiliation: CP3A Organic Synthesis Group and Services Communs, ICMMO, UMR 8182, CNRS, Université Paris Sud, Université Paris Saclay , Bât. 420, 15 rue Georges Clemenceau, 91405 Orsay cedex, France.
authors.forename: David J
authors.identifier: 0000-0002-5164-6042
authors.initials: DJ
authors.lastname: Aitken