1
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Gómez S, Ambrosetti M, Giovannini T, Cappelli C. Close-Up Look at Electronic Spectroscopic Signatures of Common Pharmaceuticals in Solution. J Phys Chem B 2024; 128:2432-2446. [PMID: 38416564 DOI: 10.1021/acs.jpcb.3c07795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
Simulating electronic properties and spectral signals requires robust computational approaches that need tuning with the system's peculiarities. In this paper, we test implicit and fully atomistic solvation models for the calculation of UV-vis and electronic circular dichroism (ECD) spectra of two pharmaceutically relevant molecules, namely, (2S)-captopril and (S)-naproxen, dissolved in aqueous solution. Room temperature molecular dynamics simulations reveal that these two drugs establish strong contacts with the surrounding solvent molecules via hydrogen bonds. Such specific interactions, which play a major role in the spectral response and are neglected in implicit approaches, are further characterized and quantified with natural bond orbital methods. Our calculations show that simulated spectra, and especially ECD, are in good agreement with experiments solely when conformational and configurational dynamics, mutual polarization, and solute-solvent repulsion effects are considered.
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Affiliation(s)
- Sara Gómez
- Scuola Normale Superiore, Classe di Scienze, Piazza dei Cavalieri 7, Pisa 56126, Italy
| | - Matteo Ambrosetti
- Scuola Normale Superiore, Classe di Scienze, Piazza dei Cavalieri 7, Pisa 56126, Italy
| | - Tommaso Giovannini
- Scuola Normale Superiore, Classe di Scienze, Piazza dei Cavalieri 7, Pisa 56126, Italy
| | - Chiara Cappelli
- Scuola Normale Superiore, Classe di Scienze, Piazza dei Cavalieri 7, Pisa 56126, Italy
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2
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Sepali C, Lafiosca P, Gómez S, Giovannini T, Cappelli C. Effective fully polarizable QM/MM approaches to compute Raman and Raman Optical Activity spectra in aqueous solution. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 305:123485. [PMID: 37827000 DOI: 10.1016/j.saa.2023.123485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 09/22/2023] [Accepted: 10/01/2023] [Indexed: 10/14/2023]
Abstract
Raman and Raman Optical Activity (ROA) signals are amply affected by solvent effects, especially in the presence of strongly solute-solvent interactions such as Hydrogen Bonding (HB). In this work, we extend the fully atomistic polarizable Quantum Mechanics/Molecular Mechanics approach, based on the Fluctuating Charges and Fluctuating Dipoles force field to the calculation of Raman and ROA spectra. Such an approach is able to accurately describe specific HB interactions, by also accounting for anisotropic contributions due to the inclusion of fluctuating dipoles. To highlight the potentiality of the novel approach, Raman and ROA spectra of L-Serine and L-Cysteine dissolved in aqueous solution are computed and compared both with alternative theoretical approaches and experimental measurements.
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Affiliation(s)
- Chiara Sepali
- Scuola Normale Superiore, Piazza dei Cavalieri, 7, Pisa, 56126, Italy
| | - Piero Lafiosca
- Scuola Normale Superiore, Piazza dei Cavalieri, 7, Pisa, 56126, Italy
| | - Sara Gómez
- Scuola Normale Superiore, Piazza dei Cavalieri, 7, Pisa, 56126, Italy
| | | | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri, 7, Pisa, 56126, Italy.
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3
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Perera AS, Carlson CD, Cheramy J, Xu Y. Infrared and vibrational circular dichroism spectra of methyl β-D-glucopyranose in water: The application of the quantum cluster growth and clusters-in-a-liquid solvation models. Chirality 2023; 35:718-731. [PMID: 37162747 DOI: 10.1002/chir.23576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/10/2023] [Accepted: 04/18/2023] [Indexed: 05/11/2023]
Abstract
The infrared (IR) and vibrational circular dichroism (VCD) spectra of methyl β-D-glucopyranose in water were measured. Both implicit and explicit solvation models were utilized to explain the observed spectra. The vast body of existing experimental and theoretical data suggested that about eight explicit water molecules are needed to account for the solvent effects, supported by the current Quantum Cluster Growth (QCG) analysis. Extensive manual and systematic conformational searches of the molecular target and its water clusters were carried out by using a recently developed conformational searching tool, conformer-rotamer ensemble sampling tool (CREST), and the microsolvation model in the associated QCG code. The Boltzmann averaged IR and VCD spectra of the methyl β-D-glucopyranose-(water)n (n = 8) conformers in the PCM of water provide better agreement with the experimental ones than those with n = 0, 1, and 2. The explicit solvation with eight water molecules was shown to greatly modify the conformational preference of methyl β-D-glucopyranose from its monomeric form. Further analyses show that the result is consistent with the existence of long-lived methyl β-D-glucopyranose monohydrates with the additional explicit water effects being accounted for with the quantum mechanical treatment of the other seven close-by water molecules in the PCM of water.
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Affiliation(s)
| | - Colton D Carlson
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Joseph Cheramy
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Yunjie Xu
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
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4
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Lemler PM, Craft CL, Pollok CH, Regan TP, Vaccaro PH. Isolated and solvated chiroptical behavior in conformationally flexible butanamines. Chirality 2023; 35:586-618. [PMID: 37550220 DOI: 10.1002/chir.23570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/15/2023] [Accepted: 04/17/2023] [Indexed: 08/09/2023]
Abstract
The nonresonant optical activity of two highly flexible aliphatic amines, (2R)-3-methyl-2-butanamine (R-MBA) and (2R)-(3,3)-dimethyl-2-butanamine (R-DMBA), has been probed under isolated and solvated conditions to examine the roles of conformational isomerism and to explore the influence of extrinsic perturbations. The optical rotatory dispersion (ORD) measured in six solvents presented uniformly negative rotatory powers over the 320-590 nm region, with the long-wavelength magnitude of chiroptical response growing nearly monotonically as the dielectric constant of the surroundings diminished. The intrinsic specific optical rotation,α λ T (in deg dm-1 [g/mL]-1 ), extracted for ambient vapor-phase samples of R-MBA [-11.031(98) and -2.29 (11)] and R-DMBA [-9.434 (72) and -1.350 (48)] at 355 and 633 nm were best reproduced by counterintuitive solvents of high polarity (yet low polarizability) like acetonitrile and methanol. Attempts to interpret observed spectral signatures quantitatively relied on the linear-response frameworks of density-functional theory (B3LYP, cam-B3LYP, and dispersion-corrected analogs) and coupled-cluster theory (CCSD), with variants of the polarizable continuum model (PCM) deployed to account for the effects of implicit solvation. Building on the identification of several low-lying equilibrium geometries (nine for R-MBA and three for R-DMBA), ensemble-averaged ORD profiles were calculated at T = 300 K by means of the independent-conformer ansatz, which enabled response properties predicted for the optimized structure of each isomer to be combined through Boltzmann-weighted population fractions derived from corresponding relative internal-energy or free-energy values, the latter of which stemmed from composite CBS-APNO and G4 analyses. Although reasonable accord between theory and experiment was realized for the isolated (vapor-phase) species, the solution-phase results were less satisfactory and tended to degrade progressively as the solvent polarity increased. These trends were attributed to solvent-mediated changes in structural parameters and energy metrics for the transition states that separate and putatively isolate the equilibrium conformations supported by the ground electronic potential-energy surface, with the resulting displacement of barrier locations and/or decrease of barrier heights compromising the underlying premise of the independent-conformer ansatz.
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Affiliation(s)
- Paul M Lemler
- Department of Chemistry, Yale University, New Haven, Connecticut, USA
- Intel Corporation, Hillsboro, Oregon, USA
| | - Clayton L Craft
- Department of Chemistry, Yale University, New Haven, Connecticut, USA
- United States Air Force Research Laboratory, Rome, New York, USA
| | - Corina H Pollok
- Department of Chemistry, Yale University, New Haven, Connecticut, USA
- Organische Chemie II, Ruhr-Universität Bochum, Bochum, Germany
| | - Thomas P Regan
- Department of Chemistry, Yale University, New Haven, Connecticut, USA
| | - Patrick H Vaccaro
- Department of Chemistry, Yale University, New Haven, Connecticut, USA
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5
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Gómez S, Giovannini T, Cappelli C. Multiple Facets of Modeling Electronic Absorption Spectra of Systems in Solution. ACS PHYSICAL CHEMISTRY AU 2022; 3:1-16. [PMID: 36718266 PMCID: PMC9881242 DOI: 10.1021/acsphyschemau.2c00050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/08/2022] [Accepted: 11/08/2022] [Indexed: 11/24/2022]
Abstract
In this Perspective, we outline the essential physicochemical aspects that need to be considered when building a reliable approach to describe absorption properties of solvated systems. In particular, we focus on how to properly model the complexity of the solvation phenomenon, arising from dynamical aspects and specific, strong solute-solvent interactions. To this end, conformational and configurational sampling techniques, such as Molecular Dynamics, have to be coupled to accurate fully atomistic Quantum Mechanical/Molecular Mechanics (QM/MM) methodologies. By exploiting different illustrative applications, we show that an effective reproduction of experimental spectral signals can be achieved by delicately balancing exhaustive sampling, hydrogen bonding, mutual polarization, and nonelectrostatic effects.
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6
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Galimberti DR. Vibrational Circular Dichroism from DFT Molecular Dynamics: The AWV Method. J Chem Theory Comput 2022; 18:6217-6230. [PMID: 36112978 PMCID: PMC9558311 DOI: 10.1021/acs.jctc.2c00736] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The paper illustrates the Activity Weighted Velocities
(AWV) methodology
to compute Vibrational Circular Dichroism (VCD) anharmonic spectra
from Density Functional Theory (DFT) molecular dynamics. AWV calculates
the spectra by the Fourier Transform of the time correlation functions
of velocities, weighted by specific observables: the Atomic Polar
Tensors (APTs) and the Atomic Axial Tensors (AATs). Indeed, AWV shows
to correctly reproduce the experimental spectra for systems in the
gas and liquid phases, both in the case of weakly and strongly interacting
systems. The comparison with the experimental spectra is striking
especially in the fingerprint region, as demonstrated by the three
benchmark systems discussed: (1S)-Fenchone in the
gas phase, (S)-(−)-Propylene oxide in the
liquid phase, and (R)-(−)-2-butanol in the
liquid phase. The time evolution of APTs and AATs can be adequately
described by a linear combination of the tensors of a small set of
appropriate reference structures, strongly reducing the computational
cost without compromising accuracy. Additionally, AWV allows the partition
of the spectral signal in its molecular components without any expensive
postprocessing and any localization of the charge density or the wave
function.
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Affiliation(s)
- Daria Ruth Galimberti
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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7
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Eikås KDR, Beerepoot MTP, Ruud K. A Computational Protocol for Vibrational Circular Dichroism Spectra of Cyclic Oligopeptides. J Phys Chem A 2022; 126:5458-5471. [PMID: 35930395 PMCID: PMC9393892 DOI: 10.1021/acs.jpca.2c02953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cyclic peptides are a promising class of compounds for next-generation antibiotics as they may provide new ways of limiting antibiotic resistance development. Although their cyclic structure will introduce some rigidity, their conformational space is large and they usually have multiple chiral centers that give rise to a wide range of possible stereoisomers. Chiroptical spectroscopies such as vibrational circular dichroism (VCD) are used to assign stereochemistry and discriminate enantiomers of chiral molecules, often in combination with electronic structure methods. The reliable determination of the absolute configuration of cyclic peptides will require robust computational methods than can identify all significant conformers and their relative population and reliably assign their stereochemistry from their chiroptical spectra by comparison with ab initio calculated spectra. We here present a computational protocol for the accurate calculation of the VCD spectra of a series of flexible cyclic oligopeptides. The protocol builds on the Conformer-Rotamer Ensemble Sampling Tool (CREST) developed by Grimme and co-workers ( Phys. Chem. Chem. Phys. 2020, 22, 7169-7192 and J. Chem. Theory. Comput. 2019, 15, 2847-2862) in combination with postoptimizations using B3LYP and moderately sized basis sets. Our recommended computational protocol for the computation of VCD spectra of cyclic oligopeptides consists of three steps: (1) conformational sampling with CREST and tight-binding density functional theory (xTB); (2) energy ranking based on single-point energy calculations as well as geometry optimization and VCD calculations of conformers that are within 2.5 kcal/mol of the most stable conformer using B3LYP/6-31+G*/CPCM; and (3) VCD spectra generation based on Boltzmann weighting with Gibbs free energies. Our protocol provides a feasible basis for generating VCD spectra also for larger cyclic peptides of biological/pharmaceutical interest and can thus be used to investigate promising compounds for next-generation antibiotics.
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Affiliation(s)
- Karolina Di Remigio Eikås
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway
| | - Maarten T P Beerepoot
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway
| | - Kenneth Ruud
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, 9037 Tromsø, Norway.,Norwegian Defence Research Establishment, P.O. Box 25, 2027 Kjeller, Norway
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8
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Morgante P, Ludowieg HD, Autschbach J. Comparative Study of Vibrational Raman Optical Activity with Different Time-Dependent Density Functional Approximations: The VROA36 Database. J Phys Chem A 2022; 126:2909-2927. [PMID: 35512708 DOI: 10.1021/acs.jpca.2c00951] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A new database, VROA36, is introduced to investigate the performance of computational approaches for vibrational Raman optical activity (VROA) calculations. The database is composed of 36 molecules with known experimental VROA spectra. It includes 93 conformers. Normal modes calculated with B3LYP-D3(BJ)/def2-TZVP are used to compute the VROA spectra with four functionals, B3LYP-D3(BJ), ωB97X-D, M11, and optimally tuned LC-PBE, as well as several basis sets. SimROA indices and frequency scaling factors are used to compare calculated spectra with each other and with experimental data. The four functionals perform equally well independently of the basis set and usually achieve good agreement with the experimental data. For molecules in near- or at-resonance conditions, the inclusion of a complex (damped) linear response approach is important to obtain physically meaningful VROA intensities. The use of any of the tested functional approximations with the def2-SVPD Gaussian-type basis set, or a basis of similar flexibility, can be recommended for efficient and reliable theoretical VROA studies.
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Affiliation(s)
- Pierpaolo Morgante
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Herbert D Ludowieg
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Jochen Autschbach
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
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9
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Yang Y, Cheramy J, Brehm M, Xu Y. Raman Optical Activity of N-Acetyl-L-Cysteine in water and in methanol: the "clusters-in-a-liquid" model and ab initio molecular dynamics simulations. Chemphyschem 2022; 23:e202200161. [PMID: 35353934 DOI: 10.1002/cphc.202200161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 03/29/2022] [Indexed: 11/06/2022]
Abstract
Raman and Raman Optical Activity (ROA) spectra of N-acetyl-L-cysteine (NALC), a flexible chiral molecule, were measured in water and in methanol to evaluate the solvent effects. Two different solvation approaches, i.e. the DFT based clusters-in-a-liquid solvent model and the ab initio molecular dynamics (AIMD) simulations, were applied to simulate the Raman and ROA spectra. Systematic conformational searches were carried out using a recently developed conformational searching tool, CREST, with the inclusion of polarizable continuum model of water and of methanol. The CREST candidates of NALC and the NALC-solvent complexes were re-optimized and their Raman and ROA simulations were done at the B3LYP-D3BJ/def2-TZVP and the B3LYP-aug-cc-pVDZ//cc-pVTZ levels. Also, AIMD simulations , which includes some anharmonic effects and all intermolecular interactions in solution, were performed. By empirically weighting the computed Raman and ROA spectra of each conformer, good agreements with the experimental data were achieved with both approaches, while AIMD offered some improvements in the carbonyl and in the low wavenumber regions over the static DFT approach. The pros and cons of these two different approaches for accounting the solvent effects on Raman and ROA of this flexible chiral system will also be discussed.
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Affiliation(s)
| | | | - Martin Brehm
- Martin-Luther-Universität Halle-Wittenberg: Martin-Luther-Universitat Halle-Wittenberg, Chemistry, GERMANY
| | - Yunjie Xu
- University of Alberta Faculty of Science, Chemistry Department, 11227 Saskatchewan Drive, T6G 2G2, Edmonton, CANADA
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10
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Gómez S, Rojas-Valencia N, Giovannini T, Restrepo A, Cappelli C. Ring Vibrations to Sense Anionic Ibuprofen in Aqueous Solution as Revealed by Resonance Raman. Molecules 2022; 27:molecules27020442. [PMID: 35056755 PMCID: PMC8780161 DOI: 10.3390/molecules27020442] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 12/31/2021] [Accepted: 01/04/2022] [Indexed: 12/07/2022] Open
Abstract
We unravel the potentialities of resonance Raman spectroscopy to detect ibuprofen in diluted aqueous solutions. In particular, we exploit a fully polarizable quantum mechanics/molecular mechanics (QM/MM) methodology based on fluctuating charges coupled to molecular dynamics (MD) in order to take into account the dynamical aspects of the solvation phenomenon. Our findings, which are discussed in light of a natural bond orbital (NBO) analysis, reveal that a selective enhancement of the Raman signal due to the normal mode associated with the C-C stretching in the ring, νC=C, can be achieved by properly tuning the incident wavelength, thus facilitating the recognition of ibuprofen in water samples.
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Affiliation(s)
- Sara Gómez
- Classe di Scienze, Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy;
- Correspondence: (S.G.); (C.C.)
| | - Natalia Rojas-Valencia
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellin 050010, Colombia; (N.R.-V.); (A.R.)
| | - Tommaso Giovannini
- Classe di Scienze, Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy;
| | - Albeiro Restrepo
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellin 050010, Colombia; (N.R.-V.); (A.R.)
| | - Chiara Cappelli
- Classe di Scienze, Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy;
- Correspondence: (S.G.); (C.C.)
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11
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12
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Rojas-Valencia N, Gómez S, Núñez-Zarur F, Cappelli C, Hadad C, Restrepo A. Thermodynamics and Intermolecular Interactions during the Insertion of Anionic Naproxen into Model Cell Membranes. J Phys Chem B 2021; 125:10383-10391. [PMID: 34492187 DOI: 10.1021/acs.jpcb.1c06766] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The insertion process of Naproxen into model dimyristoylphosphatidylcholine (DMPC) membranes is studied by resorting to state-of-the-art classical and quantum mechanical atomistic computational approaches. Molecular dynamics simulations indicate that anionic Naproxen finds an equilibrium position right at the polar/nonpolar interphase when the process takes place in aqueous environments. With respect to the reference aqueous phase, the insertion process faces a small energy barrier of ≈5 kJ mol-1 and yields a net stabilization of also ≈5 kJ mol-1. Entropy changes along the insertion path, mainly due to a growing number of realizable microstates because of structural reorganization, are the main factors driving the insertion. An attractive fluxional wall of noncovalent interactions is characterized by all-quantum descriptors of chemical bonding (natural bond orbitals, quantum theory of atoms in molecules, noncovalent interaction, density differences, and natural charges). This attractive wall originates in the accumulation of tiny transfers of electron densities to the interstitial region between the fragments from a multitude of individual intermolecular contacts stabilizing the tertiary drug/water/membrane system.
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Affiliation(s)
- Natalia Rojas-Valencia
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, 050010Medellín, Colombia.,Facultad de Ciencias Básicas, Universidad de Medellín, Carrera 87 No. 30-65, 050026 Medellín, Colombia.,Escuela de Ciencias y Humanidades, Departamento de Ciencias Básicas, Universidad Eafit, AA 3300 Medellín, Colombia
| | - Sara Gómez
- Scuola Normale Superiore, Classe di Scienze, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Francisco Núñez-Zarur
- Facultad de Ciencias Básicas, Universidad de Medellín, Carrera 87 No. 30-65, 050026 Medellín, Colombia
| | - Chiara Cappelli
- Scuola Normale Superiore, Classe di Scienze, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Cacier Hadad
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, 050010Medellín, Colombia
| | - Albeiro Restrepo
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, 050010Medellín, Colombia
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13
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Jähnigen S, Sebastiani D, Vuilleumier R. The important role of non-covalent interactions for the vibrational circular dichroism of lactic acid in aqueous solution. Phys Chem Chem Phys 2021; 23:17232-17241. [PMID: 34369531 DOI: 10.1039/d1cp03106f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We present a computational study of vibrational circular dichroism (VCD) in solutions of (S)-lactic acid, relying on ab initio molecular dynamics (AIMD) and full solvation with bulk water. We discuss the effect of the hydrogen bond network on the aggregation behaviour of the acid: while aggregates of the solute represent conditions encountered in a weakly interacting solvent, the presence of water drastically interferes with the clusters - more strongly than originally anticipated. For both scenarios we computed the VCD spectra by means of nuclear velocity perturbation theory (NVPT). The comparison with experimental data allows us to establish a VCD-structure relationship that includes the solvent network around the chiral solute. We suggest that fundamental modes with strong polarisation such as the carbonyl stretching vibration can borrow VCD from the chirally restructured solvent cage, which extends the common explanatory models of VCD generation in aqueous solution.
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Affiliation(s)
- Sascha Jähnigen
- PASTEUR, Département de chimie, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France.
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14
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Katsyuba SA, Spicher S, Gerasimova TP, Grimme S. Revisiting conformations of methyl lactate in water and methanol. J Chem Phys 2021; 155:024507. [PMID: 34266277 DOI: 10.1063/5.0057024] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The recently developed efficient protocols to implicit [Grimme et al., J. Phys. Chem. A 125, 4039-4054 (2021)] and explicit quantum mechanical modeling of non-rigid molecules in solution [Katsyuba et al., J. Phys. Chem. B 124, 6664-6670 (2020)] are applied to methyl lactate (ML). Building upon this work, a new combination scheme is proposed to incorporate solvation effects for the computation of infrared (IR) absorption spectra. Herein, Boltzmann populations calculated for implicitly solvated single conformers are used to weight the IR spectra of explicitly solvated clusters with a size of typically ten solvent molecules, i.e., accounting for the first solvation shell. It is found that in water and methanol, the most abundant conformers of ML are structurally modified relative to the gas phase, where the major form is ML1, in which the syn conformation of the -OH moiety is stabilized by a OH⋯O=C intramolecular hydrogen bond (HB). In solution, this syn conformation transforms to the gauche form because the intramolecular HB is disrupted by explicit water molecules that form intermolecular HBs with the hydroxyl and carbonyl groups. Similar changes induced by the gas-solution transition are observed for the minor conformers, ML2 and/or ML3, characterized by OH⋯OCH3 intramolecular HB in the gas phase. The relative abundance of ML1 is shown to decrease from ∼96% in gas to ∼51% in water and ∼92% in methanol. The solvent strongly influences frequencies, IR intensities, and normal modes, resulting in qualitatively different spectra compared to the gas phase. Some liquid-state conformational markers in the fingerprint region of IR spectra are revealed.
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Affiliation(s)
- Sergey A Katsyuba
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Centre of RAS, Arbuzov st. 8, 420088 Kazan, Russia
| | - Sebastian Spicher
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie der Universität Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Tatiana P Gerasimova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Centre of RAS, Arbuzov st. 8, 420088 Kazan, Russia
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie der Universität Bonn, Beringstr. 4, 53115 Bonn, Germany
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15
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Paolino M, Giovannini T, Manathunga M, Latterini L, Zampini G, Pierron R, Léonard J, Fusi S, Giorgi G, Giuliani G, Cappelli A, Cappelli C, Olivucci M. On the Transition from a Biomimetic Molecular Switch to a Rotary Molecular Motor. J Phys Chem Lett 2021; 12:3875-3884. [PMID: 33856801 DOI: 10.1021/acs.jpclett.1c00526] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The experimental investigation of the unidirectional motion characterizing the photoisomerization of single-molecule rotary motors requires accessible lab prototypes featuring an electronic circular dichroism (ECD) signal that is sensitive to the geometrical and electronic changes occurring during an ultrafast reactive process. Here we report a combined experimental/computational study of a candidate obtained via the asymmetrization of a light-driven biomimetic molecular switch. We show that the achieved motor has an ECD band that is remarkably sensitive to the isomerization motion, and it is therefore suitable for time-resolved ECD studies. However, we also find that, unexpectedly, the synthesized motor isomerizes on a time scale longer than the subpicosecond time measured for the achiral parent, a result that points to alternative candidates conserving a high reaction speed.
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Affiliation(s)
- Marco Paolino
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | | | - Madushanka Manathunga
- Chemistry Department, Bowling Green State University, Bowling Green, Ohio 43403-0001, United States
| | - Loredana Latterini
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto, 8, 06123 Perugia, Italy
| | - Giulia Zampini
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto, 8, 06123 Perugia, Italy
| | - Robin Pierron
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, F-67000 Strasbourg, France
| | - Jérémie Léonard
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, F-67000 Strasbourg, France
| | - Stefania Fusi
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Gianluca Giorgi
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Germano Giuliani
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Andrea Cappelli
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, Via A. Moro 2, 53100 Siena, Italy
| | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Massimo Olivucci
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, Via A. Moro 2, 53100 Siena, Italy
- Chemistry Department, Bowling Green State University, Bowling Green, Ohio 43403-0001, United States
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16
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Polavarapu PL, Santoro E, Covington CL, Johnson JL, Puente AR, Schley ND, Kallingathodi Z, Prakasan PC, Haleema S, Thomas AA, Ibnusaud I. How important are the intermolecular hydrogen bonding interactions in methanol solvent for interpreting the chiroptical properties? SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 247:119094. [PMID: 33142265 DOI: 10.1016/j.saa.2020.119094] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/10/2020] [Accepted: 10/12/2020] [Indexed: 06/11/2023]
Abstract
Two crispine A analogs and tetrahydrofuro[2,3-b]furan-3,3a(6aH)-diol, endowed with hydroxyl groups that can participate in intramolecular hydrogen bonding, have been synthesized and experimental vibrational circular dichroism (VCD) spectra and optical rotatory dispersion (ORD) data have been measured in CD3OD/CH3OH solvents. The absolute configurations (ACs) of these compounds have been determined using their synthetic schemes, supplemented wherever possible with X-ray diffraction data. The ACs are also analyzed with quantum chemical (QC) calculations of VCD and ORD utilizing implicit solvation as well as explicit solvation models, with the later employing classical molecular dynamics (MD) simulations. It is found that VCD calculations with implicit solvation model are adequate for determining the ACs, despite propensity of studied compounds for intermolecular hydrogen bonding between solute and solvent molecules. This observation is important because time-consuming MD simulations may not be necessary in the type of situations studied here. Additionally, it is found that the QC predicted VCD spectra provided enough diastereomer discrimination for determining the correct AC of studied compounds independently. The same observation did not apply to ORD.
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Affiliation(s)
| | - Ernesto Santoro
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA
| | - Cody L Covington
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA; Department of Chemistry, Austin Peay State University, Clarksville, TN 37044, USA
| | - Jordan L Johnson
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA
| | - Andrew R Puente
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA
| | - Nathan D Schley
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA.
| | - Zabeera Kallingathodi
- Institute for Integrated Programmes and Research in Basic Sciences, Mahatma Gandhi University, Kottayam 686560, India
| | - Prasanth C Prakasan
- Institute for Integrated Programmes and Research in Basic Sciences, Mahatma Gandhi University, Kottayam 686560, India
| | - Simimole Haleema
- Institute for Integrated Programmes and Research in Basic Sciences, Mahatma Gandhi University, Kottayam 686560, India
| | - Annu Anna Thomas
- Institute for Integrated Programmes and Research in Basic Sciences, Mahatma Gandhi University, Kottayam 686560, India
| | - Ibrahim Ibnusaud
- Institute for Integrated Programmes and Research in Basic Sciences, Mahatma Gandhi University, Kottayam 686560, India.
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17
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Marrazzini G, Giovannini T, Scavino M, Egidi F, Cappelli C, Koch H. Multilevel Density Functional Theory. J Chem Theory Comput 2021; 17:791-803. [PMID: 33449681 PMCID: PMC7880574 DOI: 10.1021/acs.jctc.0c00940] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
![]()
Following recent
developments in multilevel embedding methods,
we introduce a novel density matrix-based multilevel approach within
the framework of density functional theory (DFT). In this multilevel
DFT, the system is partitioned in an active and an inactive fragment,
and all interactions are retained between the two parts. The decomposition
of the total system is performed upon the density matrix. The orthogonality
between the two parts is maintained by solving the Kohn–Sham
equations in the MO basis for the active part only, while keeping
the inactive density matrix frozen. This results in the reduction
of computational cost. We outline the theory and implementation and
discuss the differences and similarities with state-of-the-art DFT
embedding methods. We present applications to aqueous solutions of
methyloxirane and glycidol.
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Affiliation(s)
- Gioia Marrazzini
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Tommaso Giovannini
- Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Marco Scavino
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Franco Egidi
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Henrik Koch
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
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18
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Kirchner B, Blasius J, Esser L, Reckien W. Predicting Vibrational Spectroscopy for Flexible Molecules and Molecules with Non‐Idle Environments. ADVANCED THEORY AND SIMULATIONS 2020. [DOI: 10.1002/adts.202000223] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Barbara Kirchner
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
| | - Jan Blasius
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
| | - Lars Esser
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
| | - Werner Reckien
- Mulliken Center for Theoretical Chemistry Rheinische Friedrich‐Wilhelms‐Universität Bonn Beringstr. 4+6 D‐53115 Bonn Germany
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19
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Marrazzini G, Giovannini T, Egidi F, Cappelli C. Calculation of Linear and Non-linear Electric Response Properties of Systems in Aqueous Solution: A Polarizable Quantum/Classical Approach with Quantum Repulsion Effects. J Chem Theory Comput 2020; 16:6993-7004. [PMID: 33058671 PMCID: PMC8015238 DOI: 10.1021/acs.jctc.0c00674] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Indexed: 01/10/2023]
Abstract
We present a computational study of polarizabilities and hyperpolarizabilities of organic molecules in aqueous solutions, focusing on solute-water interactions and the way they affect a molecule's linear and non-linear electric response properties. We employ a polarizable quantum mechanics/molecular mechanics (QM/MM) computational model that treats the solute at the QM level while the solvent is treated classically using a force field that includes polarizable charges and dipoles, which dynamically respond to the solute's quantum-mechanical electron density. Quantum confinement effects are also treated by means of a recently implemented method that endows solvent molecules with a parametric electron density, which exerts Pauli repulsion forces upon the solute. By applying the method to a set of aromatic molecules in solution we show that, for both polarizabilities and first hyperpolarizabilities, observed solution values are the result of a delicate balance between electrostatics, hydrogen-bonding, and non-electrostatic solute solvent interactions.
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Affiliation(s)
- Gioia Marrazzini
- Scuola
Normale Superiore, Piazza dei Cavalieri 7, Pisa 56126, Italy
| | - Tommaso Giovannini
- Department
of Chemistry, Norwegian University of Science
and Technology, Trondheim 7491, Norway
| | - Franco Egidi
- Scuola
Normale Superiore, Piazza dei Cavalieri 7, Pisa 56126, Italy
| | - Chiara Cappelli
- Scuola
Normale Superiore, Piazza dei Cavalieri 7, Pisa 56126, Italy
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20
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Giovannini T, Egidi F, Cappelli C. Theory and algorithms for chiroptical properties and spectroscopies of aqueous systems. Phys Chem Chem Phys 2020; 22:22864-22879. [PMID: 33043930 DOI: 10.1039/d0cp04027d] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Chiroptical properties and spectroscopies are valuable tools to study chiral molecules and assign absolute configurations. The spectra that result from chiroptical measurements may be very rich and complex, and hide much of their information content. For this reason, the interplay between experiments and calculations is especially useful, provided that all relevant physico-chemical interactions that are present in the experimental sample are accurately modelled. The inherent difficulty associated to the calculation of chiral signals of systems in aqueous solutions requires the development of specific tools, able to account for the peculiarities of water-solute interactions, and especially its ability to form hydrogen bonds. In this perspective we discuss a multiscale approach, which we have developed and challenged to model the most used chiroptical techniques.
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Affiliation(s)
- Tommaso Giovannini
- Department of Chemistry, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway
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21
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Giovannini T, Egidi F, Cappelli C. Molecular spectroscopy of aqueous solutions: a theoretical perspective. Chem Soc Rev 2020; 49:5664-5677. [PMID: 32744278 DOI: 10.1039/c9cs00464e] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Computational spectroscopy is an invaluable tool to both accurately reproduce the spectra of molecular systems and provide a rationalization for the underlying physics. However, the inherent difficulty to accurately model systems in aqueous solutions, owing to water's high polarity and ability to form hydrogen bonds, has severely hampered the development of the field. In this tutorial review we present a technique developed and tested in recent years based on a fully atomistic and polarizable classical modeling of water coupled with a quantum mechanical description of the solute. Thanks to its unparalleled accuracy and versatility, this method can change the perspective of computational and experimental chemists alike.
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Affiliation(s)
| | - Franco Egidi
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa, Italy.
| | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa, Italy.
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22
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Katsyuba SA, Spicher S, Gerasimova TP, Grimme S. Fast and Accurate Quantum Chemical Modeling of Infrared Spectra of Condensed-Phase Systems. J Phys Chem B 2020; 124:6664-6670. [DOI: 10.1021/acs.jpcb.0c05857] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sergey A. Katsyuba
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Centre of RAS, Arbuzov st. 8, 420088 Kazan, Russia
| | - Sebastian Spicher
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie der Universität Bonn, Beringstr. 4, 53115 Bonn, Germany
| | - Tatiana P. Gerasimova
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Centre of RAS, Arbuzov st. 8, 420088 Kazan, Russia
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie der Universität Bonn, Beringstr. 4, 53115 Bonn, Germany
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23
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Ghidinelli S, Abbate S, Koshoubu J, Araki Y, Wada T, Longhi G. Solvent Effects and Aggregation Phenomena Studied by Vibrational Optical Activity and Molecular Dynamics: The Case of Pantolactone. J Phys Chem B 2020; 124:4512-4526. [PMID: 32396357 PMCID: PMC8007093 DOI: 10.1021/acs.jpcb.0c01483] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Raman and Raman optical activity (ROA), IR, and vibrational circular dichroism (VCD) spectra of (R)- and (S)-pantolactone have been recorded in three solvents. ROA has been employed on water and DMSO solutions, VCD on DMSO and CCl4 solutions. In the last solvent, monomer-dimer equilibrium is present. Due to the low conformational flexibility of the isolated molecule and to the possibility of aggregation, this compound has been used here to test different protocols for computation of the spectroscopic responses taking into account solvent effects. Molecular dynamics (MD) simulations have been carried out together with statistical clustering methods based on collective variables to extract the structures needed to calculate the spectra. Quantum mechanical DFT calculations based on PCM are compared with approaches based on different representations of the solvent shell (MM or QM level). Appropriate treatment of the solvent permits obtaining of good band-shapes, with the added advantage that the MD analysis allows one to take into account flexibility of dimeric structures justifying the broadness of observed bands and the absence of intense VCD couplets in the carbonyl and OH stretching regions.
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Affiliation(s)
- Simone Ghidinelli
- Dipartimento di Medicina Molecolare e Traslazionale, Università di Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Sergio Abbate
- Dipartimento di Medicina Molecolare e Traslazionale, Università di Brescia, Viale Europa 11, 25123 Brescia, Italy.,Istituto Nazionale di Ottica (INO), CNR, Research Unit of Brescia, c/o CSMT, Via Branze 45, 25123 Brescia, Italy
| | - Jun Koshoubu
- JASCO Corporation, 2967-5 Ishikawa-machi, Hachioji, Tokyo 192-8537, Japan
| | - Yasuyuki Araki
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Takehiko Wada
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Giovanna Longhi
- Dipartimento di Medicina Molecolare e Traslazionale, Università di Brescia, Viale Europa 11, 25123 Brescia, Italy.,Istituto Nazionale di Ottica (INO), CNR, Research Unit of Brescia, c/o CSMT, Via Branze 45, 25123 Brescia, Italy
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24
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Polavarapu PL, Santoro E. Vibrational optical activity for structural characterization of natural products. Nat Prod Rep 2020; 37:1661-1699. [DOI: 10.1039/d0np00025f] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review presents the recent progress towards elucidating the structures of chiral natural products and applications using vibrational optical activity (VOA) spectroscopy.
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25
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Le Barbu-Debus K, Bowles J, Jähnigen S, Clavaguéra C, Calvo F, Vuilleumier R, Zehnacker A. Assessing cluster models of solvation for the description of vibrational circular dichroism spectra: synergy between static and dynamic approaches. Phys Chem Chem Phys 2020; 22:26047-26068. [DOI: 10.1039/d0cp03869e] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Solvation effects are essential for defining the shape of vibrational circular dichroism (VCD) spectra.
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Affiliation(s)
- Katia Le Barbu-Debus
- Institut des Sciences Moléculaires d’Orsay (ISMO)
- CNRS
- Université Paris-Saclay
- F-91405 Orsay
- France
| | - Jessica Bowles
- Université Paris-Saclay
- CNRS
- Institut de Chimie Physique
- UMR8000
- 91405 Orsay
| | - Sascha Jähnigen
- PASTEUR
- Département de Chimie
- Ecole Normale Supérieure
- PSL University
- Sorbonne Université
| | - Carine Clavaguéra
- Université Paris-Saclay
- CNRS
- Institut de Chimie Physique
- UMR8000
- 91405 Orsay
| | - Florent Calvo
- Université Grenoble Alpes
- CNRS
- LiPhy
- F-38000 Grenoble
- France
| | - Rodolphe Vuilleumier
- PASTEUR
- Département de Chimie
- Ecole Normale Supérieure
- PSL University
- Sorbonne Université
| | - Anne Zehnacker
- Institut des Sciences Moléculaires d’Orsay (ISMO)
- CNRS
- Université Paris-Saclay
- F-91405 Orsay
- France
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26
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Mattiat J, Luber S. Vibrational (resonance) Raman optical activity with real time time dependent density functional theory. J Chem Phys 2019; 151:234110. [DOI: 10.1063/1.5132294] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Affiliation(s)
- Johann Mattiat
- Department of Chemistry, University of Zurich, Zurich, Switzerland
| | - Sandra Luber
- Department of Chemistry, University of Zurich, Zurich, Switzerland
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27
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Rojas-Valencia N, Gómez S, Montillo S, Manrique-Moreno M, Cappelli C, Hadad C, Restrepo A. Evolution of Bonding during the Insertion of Anionic Ibuprofen into Model Cell Membranes. J Phys Chem B 2019; 124:79-90. [DOI: 10.1021/acs.jpcb.9b09705] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Natalia Rojas-Valencia
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - Sara Gómez
- Scuola Normale Superiore, Classe di Scienze, Piazza dei Cavalieri 7, 56126, Pisa, Italy
| | - Sebastian Montillo
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | | | - Chiara Cappelli
- Scuola Normale Superiore, Classe di Scienze, Piazza dei Cavalieri 7, 56126, Pisa, Italy
| | - Cacier Hadad
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - Albeiro Restrepo
- Instituto de Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
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28
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Giovannini T, Riso RR, Ambrosetti M, Puglisi A, Cappelli C. Electronic transitions for a fully polarizable QM/MM approach based on fluctuating charges and fluctuating dipoles: Linear and corrected linear response regimes. J Chem Phys 2019; 151:174104. [PMID: 31703497 DOI: 10.1063/1.5121396] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The fully polarizable Quantum Mechanics/Molecular Mechanics (QM/MM) approach based on fluctuating charges and fluctuating dipoles, named QM/FQFμ [T. Giovannini et al., J. Chem. Theory Comput. 15, 2233 (2019)], is extended to the calculation of vertical excitation energies of solvated molecular systems. Excitation energies are defined within two different solvation regimes, i.e., linear response (LR), where the response of the MM portion is adjusted to the QM transition density, and corrected-Linear Response (cLR) in which the MM response is adjusted to the relaxed QM density, thus being able to account for charge equilibration in the excited state. The model, which is specified in terms of three physical parameters (electronegativity, chemical hardness, and polarizability) is applied to vacuo-to-water solvatochromic shifts of aqueous solutions of para-nitroaniline, pyridine, and pyrimidine. The results show a good agreement with their experimental counterparts, thus highlighting the potentialities of this approach.
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Affiliation(s)
- Tommaso Giovannini
- Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | | | | | | | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
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29
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Mensch C, Bultinck P, Johannessen C. The effect of protein backbone hydration on the amide vibrations in Raman and Raman optical activity spectra. Phys Chem Chem Phys 2019; 21:1988-2005. [PMID: 30633268 DOI: 10.1039/c8cp06423g] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Raman and specifically Raman optical activity (ROA) spectroscopy are very sensitive to the solution structure and conformation of biomolecules. Because of this strong conformational sensitivity, density functional theory (DFT) calculations are often used to get a better understanding of the experimentally observed spectral patterns. While e.g. for carbohydrate structure the water molecules that surround the solute have been demonstrated to be of vital importance to get accurate modelled ROA spectra, the effect of explicit water molecules on the calculated ROA patterns of peptides and proteins is less well studied. Here, the effect of protein backbone hydration was studied using DFT calculations of HCO-(l-Ala)5-NH2 in specific secondary structure conformations with different treatments of the solvation. The effect of the explicit water molecules on the calculated spectra mainly arises from the formation of hydrogen bonds with the amide C[double bond, length as m-dash]O and N-H groups. Hydrogen bonding of water with the C[double bond, length as m-dash]O group determines the shape and position of the amide I band. The C[double bond, length as m-dash]O bond length increases upon formation of C[double bond, length as m-dash]OH2O hydrogen bonds. The effect of the explicit water molecules on the amide III vibrations arises from hydrogen bonding of the solvent with both the C[double bond, length as m-dash]O and N-H group, but their contributions to this spectral region differ: geometrically, the formation of a C[double bond, length as m-dash]OH2O bond decreases the C-N bond length, while upon forming a N-HH2O hydrogen bond, the N-H bond length increases.
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Affiliation(s)
- Carl Mensch
- Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium.
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30
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Giovannini T, Grazioli L, Ambrosetti M, Cappelli C. Calculation of IR Spectra with a Fully Polarizable QM/MM Approach Based on Fluctuating Charges and Fluctuating Dipoles. J Chem Theory Comput 2019; 15:5495-5507. [DOI: 10.1021/acs.jctc.9b00574] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tommaso Giovannini
- Department of Chemistry, Norwegian University of Science and Technology, Trondheim 7491, Norway
| | - Laura Grazioli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, Pisa 56126, Italy
| | | | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, Pisa 56126, Italy
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31
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Di Remigio R, Giovannini T, Ambrosetti M, Cappelli C, Frediani L. Fully Polarizable QM/Fluctuating Charge Approach to Two-Photon Absorption of Aqueous Solutions. J Chem Theory Comput 2019; 15:4056-4068. [DOI: 10.1021/acs.jctc.9b00305] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Roberto Di Remigio
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Tromsø - The Arctic University of Norway, N-9037 Tromsø, Norway
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Tommaso Giovannini
- Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | | | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Luca Frediani
- Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Tromsø - The Arctic University of Norway, N-9037 Tromsø, Norway
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Katsyuba SA, Zvereva EE, Grimme S. Fast Quantum Chemical Simulations of Infrared Spectra of Organic Compounds with the B97-3c Composite Method. J Phys Chem A 2019; 123:3802-3808. [PMID: 30958005 DOI: 10.1021/acs.jpca.9b01688] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability of the quantum chemical computations to reproduce spectral positions and relative intensities of infrared (IR) bands for experimental vibrational spectra of organic molecules is assessed. The efficient B97-3c density functional approximation, routinely applicable to hundreds of atoms on a single processor, has been applied for the simulation of IR spectra for species containing up to 216 atoms. The results demonstrate that B97-3c, being much faster than the well-recognized hybrid functional B3LYP, offers similarly good quantitative performance in comparison to experimental data for relative IR intensities and fundamental frequencies (ν ≤ 2200 cm-1) for isolated molecules comprising from 3 to 21 first- or second-row atoms.
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Affiliation(s)
- Sergey A Katsyuba
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Centre of RAS , Arbuzov street, 8 , Kazan 420088 , Russia
| | - Elena E Zvereva
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Centre of RAS , Arbuzov street, 8 , Kazan 420088 , Russia
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry , Institut für Physikalische und Theoretische Chemie der Universität Bonn , Beringstr. 4 , 53115 Bonn , Germany
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Johnson J, Polavarapu PL. Chiral Molecular Structures of Substituted Indans: Ring Puckering, Rotatable Substituents, and Vibrational Circular Dichroism. ACS OMEGA 2019; 4:4963-4976. [PMID: 31459680 PMCID: PMC6648482 DOI: 10.1021/acsomega.8b03628] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 02/21/2019] [Indexed: 05/06/2023]
Abstract
The chiral molecular structures of four different substituted indans, namely, (S)-1-methylindan, (R)-1-methylindan-1-d, (R)-1-aminoindan, and (S)-1-indanol, were investigated using experimental vibrational absorption and vibrational circular dichroism spectra and corresponding spectra predicted using quantum chemical (QC) calculations. All of these molecules possess two ring puckering conformations, with ring puckering leading to the pseudoequatorial substituent being approximately four times more abundant over that leading to the pseudoaxial substituent. The amino group in 1-aminoindan has three conformations arising from the rotation of NH2 group, for each ring puckering conformation, resulting in a total of six conformations. Whereas 1-indanol in the nonhydrogen-bonding solvent CCl4 also has six conformations similar to those of 1-aminoindan, 1-indanol in the hydrogen-bonding solvent DMSO-d 6 adopts numerous conformations, of which 30 conformers are considered to have at least ∼1% or more population. In DMSO solution, ring puckering leading to pseudoequatorial substituent accounts for 77% population and 23% for pseudoaxial substituent. The QC spectra predicted for the geometry optimized conformers are found to be in excellent quantitative agreement with corresponding experimental spectra in all of the molecules considered. The procedures suggested in this work are hoped to provide successful pathways for future chiral molecular structural analyses.
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Giovannini T, Lafiosca P, Chandramouli B, Barone V, Cappelli C. Effective yet reliable computation of hyperfine coupling constants in solution by a QM/MM approach: Interplay between electrostatics and non-electrostatic effects. J Chem Phys 2019; 150:124102. [DOI: 10.1063/1.5080810] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - Piero Lafiosca
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Balasubramanian Chandramouli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
- Compunet, Istituto Italiano di Tecnologia (IIT), Via Morego 30, 16163 Genova, Italy
| | - Vincenzo Barone
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
| | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
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35
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Giovannini T, Rosa M, Corni S, Cappelli C. A classical picture of subnanometer junctions: an atomistic Drude approach to nanoplasmonics. NANOSCALE 2019; 11:6004-6015. [PMID: 30869089 DOI: 10.1039/c8nr09134j] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The description of optical properties of subnanometer junctions is particularly challenging. Purely classical approaches fail, because the quantum nature of electrons needs to be considered. Here we report on a novel classical fully atomistic approach, ωFQ, based on the Drude model for conduction in metals, classical electrostatics and quantum tunneling. We show that ωFQ is able to reproduce the plasmonic behavior of complex metal subnanometer junctions with quantitative fidelity to full ab initio calculations. Besides the practical potentialities of our approach for large scale nanoplasmonic simulations, we show that a classical approach, in which the atomistic discretization of matter is properly accounted for, can accurately describe the nanoplasmonics phenomena dominated by quantum effects.
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Affiliation(s)
| | - Marta Rosa
- Department of Chemical Sciences, University of Padova, via Marzolo 1, Padova, Italy.
| | - Stefano Corni
- Department of Chemical Sciences, University of Padova, via Marzolo 1, Padova, Italy. and CNR Institute of Nanoscience, via Campi 213/A, Modena, Italy
| | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy.
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36
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Giovannini T, Puglisi A, Ambrosetti M, Cappelli C. Polarizable QM/MM Approach with Fluctuating Charges and Fluctuating Dipoles: The QM/FQFμ Model. J Chem Theory Comput 2019; 15:2233-2245. [DOI: 10.1021/acs.jctc.8b01149] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
| | | | | | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
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37
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Egidi F, Giovannini T, Del Frate G, Lemler PM, Vaccaro PH, Cappelli C. A combined experimental and theoretical study of optical rotatory dispersion for (R)-glycidyl methyl ether in aqueous solution. Phys Chem Chem Phys 2019; 21:3644-3655. [PMID: 30383044 DOI: 10.1039/c8cp04445g] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The dispersive optical activity for aqueous solutions of non-rigid (R)-glycidyl methyl ether (R-GME) has been explored synergistically from experimental and theoretical perspectives. Density functional theory analyses performed with the polarizable continuum model for implicit solvation identified nine low-lying stable conformers that are interconverted by rotation about two large-amplitude torsional coordinates. The antagonistic chiroptical signatures predicted for these structural isomers were averaged under a Boltzmann-weighting ansatz to estimate the behavior expected for a thermally equilibrated ensemble. This led to optical rotatory dispersion profiles that reproduced the overall shape of observations but failed to achieve uniform agreement with measured specific-rotation values even when anharmonic vibrational corrections were applied. A mixed QM/FQ paradigm, whereby quantum-mechanical (QM) calculations of optical activity were combined with classical molecular dynamics simulations of explicit solvation that included mutual-polarization effects by means of fluctuating charges (FQ), was enlisted to elucidate the microsolvation environment and gauge its impact upon conformer distributions and response properties. Although quantitative accord with experiments remained elusive, this approach revealed strong variations in the magnitude and sign of rotatory powers for R-GME as the configuration of surrounding water molecules evolved, thereby highlighting the inherently dynamical nature of the solvated chiroptical response, calling into question the validity of "static" descriptions based on the presumption of distinct energy minima, and giving insight into the inherent complexity posed by the modeling of such properties for solvated systems.
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Affiliation(s)
- Franco Egidi
- Scuola Normale Superiore, Piazza dei Cavalieri 7, Pisa, Italy
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Puglisi A, Giovannini T, Antonov L, Cappelli C. Interplay between conformational and solvent effects in UV-visible absorption spectra: curcumin tautomers as a case study. Phys Chem Chem Phys 2019; 21:15504-15514. [PMID: 31259324 DOI: 10.1039/c9cp00907h] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We present a combined theoretical and experimental study on the UV-vis spectra of enol-keto (EK) and keto-keto (KK) tautomeric forms of curcumin dissolved in aqueous solution. Solvent effects have been investigated by resorting to the implicit polarizable continuum model (QM/PCM) and non-polarizable and fully polarizable QM/MM approaches, the latter based on the fluctuating charges (FQ) force-field. In particular, all methods are challenged to rationalize the contribution of conformational, electrostatic and polarization effects in the calculation of the vertical excitation spectra of curcumin tautomers. The obtained results highlight that for both tautomers specific solute-solvent hydrogen-bond interactions play a minor role with respect to conformational and electrostatic effects.
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Affiliation(s)
| | | | - Liudmil Antonov
- Bulgarian Academy of Sciences, Institute of Organic Chemistry with Centre of Phytochemistry, Acad. G. Bonchev str., Bldg. 9, Sofia 1113, Bulgaria
| | - Chiara Cappelli
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy.
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Prampolini G, Ingrosso F, Segalina A, Caramori S, Foggi P, Pastore M. Dynamical and Environmental Effects on the Optical Properties of an Heteroleptic Ru(II)–Polypyridine Complex: A Multilevel Approach Combining Accurate Ground and Excited State QM-Derived Force Fields, MD and TD-DFT. J Chem Theory Comput 2018; 15:529-545. [DOI: 10.1021/acs.jctc.8b01031] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Giacomo Prampolini
- Istituto di Chimica dei Composti OrganoMetallici (ICCOM-CNR), Area della Ricerca, via G. Moruzzi 1, I-56124 Pisa, Italy
| | - Francesca Ingrosso
- Université de Lorraine, CNRS, Laboratoire de Physique et Chimie Théoriques, F-54000 Nancy, France
| | - Alekos Segalina
- Université de Lorraine, CNRS, Laboratoire de Physique et Chimie Théoriques, F-54000 Nancy, France
| | - Stefano Caramori
- Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Ferrara, Via Luigi Borsari 46, I-44100, Ferrara, Italy
| | - Paolo Foggi
- European Laboratory for Non Linear Spectroscopy (LENS), Università di Firenze, Via Nello Carrara 1, I-50019 Sesto Fiorentino Florence, Italy
- INO−CNR, Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche, Largo Fermi 6, I-50125 Florence, Italy
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto 8, I-06123 Perugia, Italy
| | - Mariachiara Pastore
- Université de Lorraine, CNRS, Laboratoire de Physique et Chimie Théoriques, F-54000 Nancy, France
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Rode JE, Górecki M, Witkowski S, Frelek J. Solvation of 2-(hydroxymethyl)-2,5,7,8-tetramethyl-chroman-6-ol revealed by circular dichroism: a case of chromane helicity rule breaking. Phys Chem Chem Phys 2018; 20:22525-22536. [PMID: 30140796 DOI: 10.1039/c8cp02491j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The primary goal of this work is to clarify why 2-(hydroxymethyl)-2,5,7,8-tetramethyl-chroman-6-ol {(S)-TMChM} deviates from the chromane helicity rule under solvent change. The rule, applicable to determining the absolute configuration of molecules containing the chromane chromophore, binds the sign of the 1Lb Cotton effect (CE) with the helicity of the dihydropyran ring. In case of TMChM, however, this CE exhibits extreme solvent dependence: it is negative in non-coordinating solvents and positive in coordinating ones, irrespective of the helicity of the heterocyclic ring. TD-DFT calculations using PCM and hybrid solvation models were performed to explain origin of this phenomenon. It turned out that the 1Lb CE sign directly depends on the position of the phenolic OH group at carbon atom C6 (OHC6). In the absence of interactions with solvents (as in CCl4 or nC6H14) or when a solvent plays proton donor role (as in CHCl3), the OHC6 lies in the phenyl plane and the 1Lb CE sign follows the P/M helicity rule. In contrast, in proton acceptor solvents, like DMSO, CH3OH or CH3CN, the OHC6 group is deflected from the phenyl plane, and the 1Lb CE sign of individual (S)-TMChM conformers depends on the sector in which the OHC6 is located. Thus, in solution, the 1Lb CE sign is an average over different orientations of the OHC6 group and can be positive (as in DMSO and CH3OH) or negative (as in CH3CN) which means that it does not follow the chromane helicity rule. The impact of OHC6 on the 1Lb CE sign and thus the conclusions for the stereochemistry of chromans are demonstrated here for the first time. Additionally, a comparison of experimental and simulated ECD spectra, supported by VCD data, allowed to determine the geometry of intermolecular clusters formed in different solvents.
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Affiliation(s)
- Joanna E Rode
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
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