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Papers by Jean-Yves Le Questel
La modelisation de molecules organiques bifonctionnelles en differents systemes reproduisant les ... more La modelisation de molecules organiques bifonctionnelles en differents systemes reproduisant les interactions entre deux groupes fonctionnels potentiellement accepteurs de liaison hydrogene nous a permis de degager trois regles permettant de prevoir l'affinite de liaison hydrogene d'une molecule polyfonctionnelle a partir de sa structure: 1) les sites potentiels accepteurs de liaison hydrogene (principalement les heteroatomes et les systemes ), sont pratiquement toujours actifs; 2) lorsque deux sites potentiels, l'un donneur d, l'autre accepteur d'electrons a, sont separes par un groupe transmetteur permettant leur conjugaison, seul le groupe a est accepteur de liaison hydrogene (systeme push-pull); 3) dans les systemes push-pull, le groupe transmetteur revet une importance particuliere pour moduler la basicite de liaison hydrogene du groupe accepteur a. La validite de ces regles est testee et confirmee au cours de leur application a des molecules d'interet biologique (la progesterone, le valium, la cafeine et la nicotine ont par exemple ete etudiees). Dans une derniere partie, nous comparons les sites de liaison hydrogene et de protonation de molecules polyfonctionnelles a partir de donnees relatives a la basicite de bronsted en solution aqueuse et de resultats acquis a l'etat gazeux
Journal of the Chemical Society, 1995
HAL (Le Centre pour la Communication Scientifique Directe), 1996
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
HAL (Le Centre pour la Communication Scientifique Directe), 2016
Journal of Medicinal Chemistry, Jun 19, 2009
Journal of Physical Chemistry A, May 14, 2010
The conformational preferences of a new bis-pyrrole derivative and its bis-pyridazine precursor h... more The conformational preferences of a new bis-pyrrole derivative and its bis-pyridazine precursor have been investigated through quantum chemistry calculations (HF, DFT(MPWB1K), LMP2) and observations in the solid state. The global energetic minima are planar for both structures, with the conformational preferences being explained by pi-electronic conjugation between the aromatic systems and the occurrence of intramolecular hydrogen bonds (HB). For the bis-pyridazine derivative, the all-anti preferred conformation results from CH...Nsp(2) HB whereas the all-syn conformation of the bis-pyrrole is partly due to NH...Nsp(2) HB. For both systems, the validity of the theoretical conformational features is confirmed through the excellent agreement with the experimental data available. Calculations of electrostatic potential computed on the molecular surface of the various structures and their building blocks allow the variations to be rationalized in terms of molecular structure and are used to analyze the HB donor and acceptor sites of the compounds. The HB interaction sites predicted from the quantum chemical calculations are confirmed through the HB interactions observed in relevant crystal structures.
Nuclear Medicine and Biology, May 1, 2022
HAL (Le Centre pour la Communication Scientifique Directe), 2014
248th National Meeting of the American-Chemical-Society (ACS), San Francisco, CA, AUG 10-14, 2014... more 248th National Meeting of the American-Chemical-Society (ACS), San Francisco, CA, AUG 10-14, 2014International audienc
HAL (Le Centre pour la Communication Scientifique Directe), 2016
Chemistry: A European Journal, Dec 27, 2016
Bioorganic & Medicinal Chemistry Letters, 2023
Elsevier eBooks, 2019
Abstract Hydrogen bonding represents the most specific molecular interaction in biological recogn... more Abstract Hydrogen bonding represents the most specific molecular interaction in biological recognition processes, and the controlled modulation of hydrogen-bond properties of functional groups present in ligands is of great interest. The introduction of fluorine atoms in the vicinity of functional groups is one of the ways this can be achieved. In this chapter, a number of hydrogen-bond acidity scales are reviewed, with a focus on the hydrogen-bond donating capacity of alcohols. An overview of experimental data showing how the hydrogen-bond donating capacity of alcohols is modulated by fluorination is given, followed by a rationalization of these results. Computational methodology to describe and predict hydrogen bonds is discussed, with a focus on a convenient method for accurate alcohol hydrogen-bond donating capacity prediction.
HAL (Le Centre pour la Communication Scientifique Directe), 2018
256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanot... more 256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanotechnology and Beyond, Boston, MA, AUG 19-23, 201
HAL (Le Centre pour la Communication Scientifique Directe), 1995
Chemistry: A European Journal, Feb 2, 2007
Journal of Molecular Structure, Oct 1, 2022
Proteins, Jun 28, 2014
Structural and theoretical studies on the geometrical features of a hydrogen-bond network occurri... more Structural and theoretical studies on the geometrical features of a hydrogen-bond network occurring in the binding site of nicotinic acetylcholine receptors (nAChRs) and composed of interconnected WxPD (Trp-x-Pro-Asp) and SWyz (Ser-Trp-yz) sequences from loops A and B, respectively, have been carried out. Multiple sequence alignments using as template the sequence of the apoform of Aplysia californica Acetylcholine binding protein (Ac-AChBP) show the strict conservation of Serine and Tryptophan residues of the loop B SWyz sequence. Considering a sample of 19 high resolution AChBP structures, the strong conformational preferences of the key Tryptophan residue has been pointing out, whatever the form, free or bounded, of AChBP. The geometry of the motif hydrogen
Chemical Physics Letters, 2012
Abstract We use dispersion-corrected density functional theory approaches (DFT-D) to investigate ... more Abstract We use dispersion-corrected density functional theory approaches (DFT-D) to investigate the structure and properties of complexes constituted of an aromatic tweezer and aromatic molecules. It turns out that a B97-D/6-31G(d) geometry optimisation yields reasonably accurate structural parameters, whereas larger basis sets and the latest DFT-D models are required to adequately mimic the complexation energies measured through NMR experiments. This contribution highlights that ab initio schemes may be pertinent to investigate the binding energies of large association complexes, even when the studied interaction is relatively weak and shows a non specific character, with a significant dispersion contribution.
La modelisation de molecules organiques bifonctionnelles en differents systemes reproduisant les ... more La modelisation de molecules organiques bifonctionnelles en differents systemes reproduisant les interactions entre deux groupes fonctionnels potentiellement accepteurs de liaison hydrogene nous a permis de degager trois regles permettant de prevoir l'affinite de liaison hydrogene d'une molecule polyfonctionnelle a partir de sa structure: 1) les sites potentiels accepteurs de liaison hydrogene (principalement les heteroatomes et les systemes ), sont pratiquement toujours actifs; 2) lorsque deux sites potentiels, l'un donneur d, l'autre accepteur d'electrons a, sont separes par un groupe transmetteur permettant leur conjugaison, seul le groupe a est accepteur de liaison hydrogene (systeme push-pull); 3) dans les systemes push-pull, le groupe transmetteur revet une importance particuliere pour moduler la basicite de liaison hydrogene du groupe accepteur a. La validite de ces regles est testee et confirmee au cours de leur application a des molecules d'interet biologique (la progesterone, le valium, la cafeine et la nicotine ont par exemple ete etudiees). Dans une derniere partie, nous comparons les sites de liaison hydrogene et de protonation de molecules polyfonctionnelles a partir de donnees relatives a la basicite de bronsted en solution aqueuse et de resultats acquis a l'etat gazeux
Journal of the Chemical Society, 1995
HAL (Le Centre pour la Communication Scientifique Directe), 1996
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
HAL (Le Centre pour la Communication Scientifique Directe), 2016
Journal of Medicinal Chemistry, Jun 19, 2009
Journal of Physical Chemistry A, May 14, 2010
The conformational preferences of a new bis-pyrrole derivative and its bis-pyridazine precursor h... more The conformational preferences of a new bis-pyrrole derivative and its bis-pyridazine precursor have been investigated through quantum chemistry calculations (HF, DFT(MPWB1K), LMP2) and observations in the solid state. The global energetic minima are planar for both structures, with the conformational preferences being explained by pi-electronic conjugation between the aromatic systems and the occurrence of intramolecular hydrogen bonds (HB). For the bis-pyridazine derivative, the all-anti preferred conformation results from CH...Nsp(2) HB whereas the all-syn conformation of the bis-pyrrole is partly due to NH...Nsp(2) HB. For both systems, the validity of the theoretical conformational features is confirmed through the excellent agreement with the experimental data available. Calculations of electrostatic potential computed on the molecular surface of the various structures and their building blocks allow the variations to be rationalized in terms of molecular structure and are used to analyze the HB donor and acceptor sites of the compounds. The HB interaction sites predicted from the quantum chemical calculations are confirmed through the HB interactions observed in relevant crystal structures.
Nuclear Medicine and Biology, May 1, 2022
HAL (Le Centre pour la Communication Scientifique Directe), 2014
248th National Meeting of the American-Chemical-Society (ACS), San Francisco, CA, AUG 10-14, 2014... more 248th National Meeting of the American-Chemical-Society (ACS), San Francisco, CA, AUG 10-14, 2014International audienc
HAL (Le Centre pour la Communication Scientifique Directe), 2016
Chemistry: A European Journal, Dec 27, 2016
Bioorganic & Medicinal Chemistry Letters, 2023
Elsevier eBooks, 2019
Abstract Hydrogen bonding represents the most specific molecular interaction in biological recogn... more Abstract Hydrogen bonding represents the most specific molecular interaction in biological recognition processes, and the controlled modulation of hydrogen-bond properties of functional groups present in ligands is of great interest. The introduction of fluorine atoms in the vicinity of functional groups is one of the ways this can be achieved. In this chapter, a number of hydrogen-bond acidity scales are reviewed, with a focus on the hydrogen-bond donating capacity of alcohols. An overview of experimental data showing how the hydrogen-bond donating capacity of alcohols is modulated by fluorination is given, followed by a rationalization of these results. Computational methodology to describe and predict hydrogen bonds is discussed, with a focus on a convenient method for accurate alcohol hydrogen-bond donating capacity prediction.
HAL (Le Centre pour la Communication Scientifique Directe), 2018
256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanot... more 256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanotechnology and Beyond, Boston, MA, AUG 19-23, 201
HAL (Le Centre pour la Communication Scientifique Directe), 1995
Chemistry: A European Journal, Feb 2, 2007
Journal of Molecular Structure, Oct 1, 2022
Proteins, Jun 28, 2014
Structural and theoretical studies on the geometrical features of a hydrogen-bond network occurri... more Structural and theoretical studies on the geometrical features of a hydrogen-bond network occurring in the binding site of nicotinic acetylcholine receptors (nAChRs) and composed of interconnected WxPD (Trp-x-Pro-Asp) and SWyz (Ser-Trp-yz) sequences from loops A and B, respectively, have been carried out. Multiple sequence alignments using as template the sequence of the apoform of Aplysia californica Acetylcholine binding protein (Ac-AChBP) show the strict conservation of Serine and Tryptophan residues of the loop B SWyz sequence. Considering a sample of 19 high resolution AChBP structures, the strong conformational preferences of the key Tryptophan residue has been pointing out, whatever the form, free or bounded, of AChBP. The geometry of the motif hydrogen
Chemical Physics Letters, 2012
Abstract We use dispersion-corrected density functional theory approaches (DFT-D) to investigate ... more Abstract We use dispersion-corrected density functional theory approaches (DFT-D) to investigate the structure and properties of complexes constituted of an aromatic tweezer and aromatic molecules. It turns out that a B97-D/6-31G(d) geometry optimisation yields reasonably accurate structural parameters, whereas larger basis sets and the latest DFT-D models are required to adequately mimic the complexation energies measured through NMR experiments. This contribution highlights that ab initio schemes may be pertinent to investigate the binding energies of large association complexes, even when the studied interaction is relatively weak and shows a non specific character, with a significant dispersion contribution.