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Muñoz-Gacitúa D, Monroy-Cárdenas M, Araya-Maturana R, Weiss-López B. Characterization of an anionic membrane mimetic with natural phospholipid content and magnetic orienting capabilities. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2020.114616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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2
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Patyk-Kaźmierczak E, Kaźmierczak M. A new high-pressure benzocaine polymorph - towards understanding the molecular aggregation in crystals of an important active pharmaceutical ingredient (API). ACTA CRYSTALLOGRAPHICA SECTION B, STRUCTURAL SCIENCE, CRYSTAL ENGINEERING AND MATERIALS 2020; 76:56-64. [PMID: 32831241 DOI: 10.1107/s2052520619016548] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 12/08/2019] [Indexed: 06/11/2023]
Abstract
Benzocaine (BZC), an efficient and highly permeable anaesthetic and an active pharmaceutical ingredient of many commercially available drugs, was studied under high pressure up to 0.78 GPa. As a result, new BZC polymorph (IV) was discovered. The crystallization of polymorph (IV) can be initiated by heating crystals of polymorph (I) at a pressure of at least 0.45 GPa or by their compression to 0.60 GPa. However, no phase transition from polymorph (I) to (IV) was observed. Although polymorph (IV) exhibits the same main aggregation motif as in previously reported BZC polymorphs (I)-(III), i.e. a hydrogen-bonded ribbon, its molecular packing and hydrogen-bonding pattern differ considerably. The N-H...N hydrogen bonds joining parallel BZC ribbons in crystals at ambient pressure are eliminated in polymorph (IV), and BZC ribbons become positioned at an angle of about 80°. Unfortunately, crystals of polymorph (IV) were not preserved on pressure release, and depending on the decompression protocol they transformed into polymorph (II) or (I).
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Affiliation(s)
- Ewa Patyk-Kaźmierczak
- Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, Poznań, 61-614, Poland
| | - Michał Kaźmierczak
- Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, Poznań, 61-614, Poland
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3
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León I, Lesarri A, Fernández JA. Evaluation of the aggregation process in a mixture of propofol and benzocaine. Phys Chem Chem Phys 2019; 21:3537-3544. [PMID: 30137107 DOI: 10.1039/c8cp04386h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report on a mass-resolved IR spectrosopic study on propofol-benzocaine aggregates. This is a complex system due to the several conformational isomers that both monomers may adopt and to the combination of functional groups they present, which allow the molecules to interact in many possible ways. However, our results demonstrate that a single conformation is favored for each stoichiometry. In the heterodimer, propofol acts as a proton donor to the ester group of benzocaine, while the whole cluster is stabilized by dispersive forces. These dispersive forces account for an important part of the system's stabilization energy as the calculations suggest. Propofol does not show any affinity for the amino group of benzocaine, even when a second molecule of propofol is introduced. These results demonstrate the difficulty in anticipating the aggregation preferences of even small organic molecules.
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Affiliation(s)
- I León
- Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country, Barrio Sarriena s/n, 48940 Leioa, Spain.
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4
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Kumar S, Singh SK, Vaishnav JK, Hill JG, Das A. Interplay among Electrostatic, Dispersion, and Steric Interactions: Spectroscopy and Quantum Chemical Calculations of π-Hydrogen Bonded Complexes. Chemphyschem 2017; 18:828-838. [PMID: 28124829 DOI: 10.1002/cphc.201601405] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 01/24/2017] [Indexed: 11/07/2022]
Abstract
π-Hydrogen bonding interactions are ubiquitous in both materials and biology. Despite their relatively weak nature, great progress has been made in their investigation by experimental and theoretical methods, but this becomes significantly more complicated when secondary intermolecular interactions are present. In this study, the effect of successive methyl substitution on the supramolecular structure and interaction energy of indole⋅⋅⋅methylated benzene (ind⋅⋅⋅n-mb, n=1-6) complexes is probed through a combination of supersonic jet experiments and benchmark-quality quantum chemical calculations. It is demonstrated that additional secondary interactions introduce a subtle interplay among electrostatic and dispersion forces, as well as steric repulsion, which fine-tunes the overall structural motif. Resonant two-photon ionization and IR-UV double-resonance spectroscopy techniques are used to probe jet-cooled ind⋅⋅⋅n-mb (n=2, 3, 6) complexes, with redshifting of the N-H IR stretching frequency showing that increasing the degree of methyl substitution increases the strength of the primary N-H⋅⋅⋅π interaction. Ab initio harmonic frequency and binding energy calculations confirm this trend for all six complexes. Electronic spectra of the three dimers are broad and structureless, with quantum chemical calculations revealing that this is likely to be due to multiple tilted conformations of each dimer possessing similar stabilization energies.
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Affiliation(s)
- Sumit Kumar
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Dr. Homi Bhabha Road, Pashan, Pune, 411008, Maharashtra, India.,Present address: Department of Dynamics at Surfaces, Max Planck Institute of Biophysical Chemistry, Am Faßberg 11, 37077, Gottingen, Germany
| | - Santosh K Singh
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Dr. Homi Bhabha Road, Pashan, Pune, 411008, Maharashtra, India
| | - Jamuna K Vaishnav
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Dr. Homi Bhabha Road, Pashan, Pune, 411008, Maharashtra, India.,Present address: Indian Institute of Technology (IIT) Indore, Khandwa Rd, Simrol, Madhya, Pradesh, 452020, India
| | - J Grant Hill
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research (IISER), Dr. Homi Bhabha Road, Pashan, Pune, 411008, Maharashtra, India
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5
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Pérez C, Caballero-Mancebo E, Lesarri A, Cocinero EJ, Alkorta I, Suenram RD, Grabow JU, Pate BH. The Conformational Map of Volatile Anesthetics: Enflurane Revisited. Chemistry 2016; 22:9804-11. [PMID: 27258776 DOI: 10.1002/chem.201601201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Indexed: 11/10/2022]
Abstract
Previous ambiguities in the conformational and structural landscape of the volatile anesthetic enflurane have been solved combining microwave spectroscopy in a jet expansion and ab initio calculations. The broadband (2-18 GHz) rotational spectra identified three different rotamers, sharing a common trans ether skeleton but differing in the ±gauche/trans position of the terminal chlorine atom. For each chlorine conformation two different gauche orientations were predicted for the opposite difluoromethyl group, but only one is experimentally observable due to collisional relaxation in the jet. The experimental dataset comprised nine different isotopologues ((35) Cl, (37) Cl, (13) C) and a large number (>6500) of rotational transitions. The inertial data provided structural information using the substitution and effective procedures. The structural preferences were rationalized with additional ab initio, natural-bond-orbital and non-covalent-interaction analysis, which suggest that plausible anomeric effects at the difluoromethyl group could be overridden by other intramolecular effects. The difluoromethyl orientation thus reflects a minimization of inter-fluorine repulsions while maximizing F⋅⋅⋅H attractive interactions. A comparison with previous electron diffraction and spectroscopic data in the gas and condensed phases finally resulted in a comprehensive description of this ether, completing a rotational description of the most common multi-halogenated anesthetics.
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Affiliation(s)
- Cristóbal Pérez
- Department of Chemistry, University of Virginia, McCormick Rd., Charlottesville, Virginia, 22904, USA.,Max-Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Elena Caballero-Mancebo
- Departamento de Química Física y Química Inorgánica, Universidad de Valladolid, 47011, Valladolid, Spain
| | - Alberto Lesarri
- Departamento de Química Física y Química Inorgánica, Universidad de Valladolid, 47011, Valladolid, Spain.
| | - Emilio J Cocinero
- Departamento de Química Física, Universidad del País Vasco, Ap. 644, 48080, Bilbao, Spain
| | - Ibon Alkorta
- Instituto de Química Médica, CSIC, Madrid, Spain
| | - Richard D Suenram
- Department of Chemistry, University of Virginia, McCormick Rd., Charlottesville, Virginia, 22904, USA
| | - Jens-Uwe Grabow
- Institut für Physikalische Chemie and Elektrochemie, Lehrgebiet A, Gottfried-Wilhelm-Leibniz-Universität, Callinstrasse 3A, 30167, Hannover, Germany
| | - Brooks H Pate
- Department of Chemistry, University of Virginia, McCormick Rd., Charlottesville, Virginia, 22904, USA.
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6
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Uriarte I, Écija P, Spada L, Zabalza E, Lesarri A, Basterretxea FJ, Fernández JA, Caminati W, Cocinero EJ. Potential energy surface of fluoroxene: experiment and theory. Phys Chem Chem Phys 2016; 18:3966-74. [DOI: 10.1039/c5cp06522d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The potential energy surface (PES) of the general anesthetic fluoroxene was probed in a supersonic jet expansion using broadband CP-FTMW spectroscopy and theoretical calculations.
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Affiliation(s)
- Iciar Uriarte
- Departamento de Química Física
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- Bilbao
- Spain
| | - Patricia Écija
- Departamento de Química Física
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- Bilbao
- Spain
| | - Lorenzo Spada
- Departamento de Química Física
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- Bilbao
- Spain
| | - Eneko Zabalza
- Departamento de Química Física
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- Bilbao
- Spain
| | - Alberto Lesarri
- Departamento de Química Física y Química Inorgánica
- Facultad de Ciencias
- Universidad de Valladolid
- Valladolid
- Spain
| | - Francisco J. Basterretxea
- Departamento de Química Física
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- Bilbao
- Spain
| | - José A. Fernández
- Departamento de Química Física
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- Bilbao
- Spain
| | | | - Emilio J. Cocinero
- Departamento de Química Física
- Facultad de Ciencia y Tecnología
- Universidad del País Vasco (UPV/EHU)
- Bilbao
- Spain
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7
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León I, Arnáiz PF, Usabiaga I, Fernández JA. Mass resolved IR spectroscopy of aniline–water aggregates. Phys Chem Chem Phys 2016; 18:27336-27341. [DOI: 10.1039/c6cp04373a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aniline is the simplest aromatic amine and therefore it is a prototypical system to study the microhydration and excited state dynamics of aromatic amines.
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Affiliation(s)
- I. León
- Department of Physical Chemistry
- Faculty of Science and Technology
- University of the Basque Country
- 48940 Leioa
- Spain
| | - P. F. Arnáiz
- Department of Physical Chemistry
- Faculty of Science and Technology
- University of the Basque Country
- 48940 Leioa
- Spain
| | - I. Usabiaga
- Department of Physical Chemistry
- Faculty of Science and Technology
- University of the Basque Country
- 48940 Leioa
- Spain
| | - J. A. Fernández
- Department of Physical Chemistry
- Faculty of Science and Technology
- University of the Basque Country
- 48940 Leioa
- Spain
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Yan B, Jaeqx S, van der Zande WJ, Rijs AM. A conformation-selective IR-UV study of the dipeptides Ac-Phe-Ser-NH2 and Ac-Phe-Cys-NH2: probing the SH···O and OH···O hydrogen bond interactions. Phys Chem Chem Phys 2015; 16:10770-8. [PMID: 24756311 DOI: 10.1039/c4cp00810c] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The conformational preferences of peptides are mainly controlled by the stabilizing effect of intramolecular interactions. In peptides with polar side chains, not only the backbone but also the side chain interactions determine the resulting conformations. In this paper, the conformational preferences of the capped dipeptides Ac-Phe-Ser-NH2 (FS) and Ac-Phe-Cys-NH2 (FC) are resolved under laser-desorbed jet cooling conditions using IR-UV ion dip spectroscopy and density functional theory (DFT) quantum chemistry calculations. As serine (Ser) and cysteine (Cys) only differ in an OH (Ser) or SH (Cys) moiety; this subtle alteration allows us to study the effect of the difference in hydrogen bonding for an OH and SH group in detail, and its effect on the secondary structure. IR absorption spectra are recorded in the NH stretching region (3200-3600 cm(-1)). In combination with quantum chemical calculations the spectra provide a direct view of intramolecular interactions. Here, we show that both FS as FC share a singly γ-folded backbone conformation as the most stable conformer. The hydrogen bond strength of OH···O (FS) is stronger than that of SH···O (FC), resulting in a more compact gamma turn structure. A second conformer is found for FC, showing a β turn interaction.
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Affiliation(s)
- Bin Yan
- Radboud University Nijmegen, Institute for Molecules and Materials, FELIX Facility, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands.
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Wang C, Jiang Y, Zhang R, Lin Z. Intermolecular π/π and H/π interactions in dimers researched by different computational methods. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2014. [DOI: 10.1142/s0219633614500576] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The analysis of π/π and H /π interactions in complexes are a challenging aspect of theoretical research. Due to the different approximations of different levels of theory, results tend to be inconsistent. We compared the reliabilities of HF, SVWN, M06L, PW91, BLYP, B3LYP, BHandHLYP, B97D, MP2, and DFTB-D approaches in researching π/π and H /π interactions by calculating the binding energies of five benzene-containing dimers. The effects of 6-31+G**, 6-311++G** and 6-311++G(2df,2p) basis sets on the results were analyzed too. We found that the DFTB-D and B97D methods combined with the 6-311++G** basis set perform well for dimers that contain π/π and H /π interactions. With high efficiency and satisfactory precision, DFTB-D is helpful for the calculation of complexes containing π/π and H /π stacking. We further calculated the structures and properties of phenylalanine-containing dimers using the DFTB-D and B97D methods. The properties of low energy conformers such as rotational constants, dipole moments and molecular orbitals were also analyzed. These data should be helpful for research into systems that contain π/π and H /π stacking.
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Affiliation(s)
- Cuihong Wang
- School of Science, TianJin ChengJian University, Tianjin 300384, P. R. China
| | - Yue Jiang
- School of Science, TianJin ChengJian University, Tianjin 300384, P. R. China
| | - Ruiqin Zhang
- Department of Physics and Materials Science, City University of Hong Kong, Hong Kong, P. R. China
| | - Zijing Lin
- Department of Physics & Collaborative Innovation Center of Suzhou Nano Science and Technology, University of Science and Technology of China, Hefei 230026, P. R. China
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Rijs AM, Oomens J. IR Spectroscopic Techniques to Study Isolated Biomolecules. Top Curr Chem (Cham) 2014; 364:1-42. [DOI: 10.1007/128_2014_621] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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