1
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Huynh H, Le K, Vu L, Nguyen T, Holcomb M, Forli S, Phan H. Synergy of machine learning and density functional theory calculations for predicting experimental Lewis base affinity and Lewis polybase binding atoms. J Comput Chem 2024; 45:1552-1561. [PMID: 38500409 PMCID: PMC11099847 DOI: 10.1002/jcc.27329] [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: 10/31/2023] [Revised: 01/26/2024] [Accepted: 01/31/2024] [Indexed: 03/20/2024]
Abstract
Investigation of Lewis acid-base interactions has been conducted by ab initio calculations and machine learning (ML) models. This study aims to resolve two critical tasks that have not been quantitatively investigated. First, ML models developed from density functional theory (DFT) calculations predict experimental BF3 affinity with Pearson correlation coefficients around 0.9 and mean absolute errors around 10 kJ mol-1. The ML models are trained by DFT-calculated BF3 affinity of more than 3000 adducts, with input features readily obtained by rdkit. Second, the ML models have the capability of predicting the relative strength of Lewis base binding atoms in Lewis polybases, which is either an extremely challenging task to conduct experimentally or a computationally expensive task for ab initio methods. The study demonstrates and solidifies the potential of combining DFT calculations and ML models to predict experimental properties, especially those that are scarce and impractical to empirically acquire.
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Affiliation(s)
- Hieu Huynh
- Fulbright University Vietnam, Ho Chi Minh city, Vietnam, Ho Chi Minh City 700000
| | - Khanh Le
- Fulbright University Vietnam, Ho Chi Minh city, Vietnam, Ho Chi Minh City 700000
| | - Linh Vu
- Fulbright University Vietnam, Ho Chi Minh city, Vietnam, Ho Chi Minh City 700000
| | - Trang Nguyen
- Fulbright University Vietnam, Ho Chi Minh city, Vietnam, Ho Chi Minh City 700000
| | - Matthew Holcomb
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037 USA
| | - Stefano Forli
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037 USA
| | - Hung Phan
- Fulbright University Vietnam, Ho Chi Minh city, Vietnam, Ho Chi Minh City 700000
- Soka University of America, Aliso Viejo, California, United States, CA 92656
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2
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Cador A, Hoffmann G, Tognetti V, Joubert L. A theoretical study on aza-Michael additions. Theor Chem Acc 2022. [DOI: 10.1007/s00214-022-02921-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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3
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Kinetic Characterization of Cerium and Gallium Ions as Inhibitors of Cysteine Cathepsins L, K, and S. Int J Mol Sci 2022; 23:ijms23168993. [PMID: 36012257 PMCID: PMC9409168 DOI: 10.3390/ijms23168993] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/08/2022] [Accepted: 08/11/2022] [Indexed: 11/24/2022] Open
Abstract
Heavy metal ions can disrupt biological functions via multiple molecular mechanisms, including inhibition of enzymes. We investigate the interactions of human papain-like cysteine endopeptidases cathepsins L, K, and S with gallium and cerium ions, which are associated with medical applications. We compare these results with zinc and lead, which are known to inhibit thiol enzymes. We show that Ga3+, Ce3+, and Ce4+ ions inhibit all tested peptidases with inhibition constants in the low micromolar range (between 0.5 µM and 10 µM) which is comparable to Zn2+ ions, whereas inhibition constants of Pb2+ ions are one order of magnitude higher (30 µM to 150 µM). All tested ions are linear specific inhibitors of cathepsin L, but cathepsins K and S are inhibited by Ga3+, Ce3+, and Ce4+ ions via hyperbolic inhibition mechanisms. This indicates a mode of interaction different from that of Zn2+ and Pb2+ ions, which act as linear specific inhibitors of all peptidases. All ions also inhibit the degradation of insoluble elastin, which is a common target of these peptidases in various inflammatory diseases. Our results suggest that these ions and their compounds have the potential to be used as cysteine cathepsin inhibitors in vitro and possibly in vivo.
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4
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Miranda-Quintana RA, Heidar-Zadeh F, Fias S, Chapman AEA, Liu S, Morell C, Gómez T, Cárdenas C, Ayers PW. Molecular interactions from the density functional theory for chemical reactivity: Interaction chemical potential, hardness, and reactivity principles. Front Chem 2022; 10:929464. [PMID: 35936089 PMCID: PMC9352952 DOI: 10.3389/fchem.2022.929464] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/27/2022] [Indexed: 11/13/2022] Open
Abstract
In the first paper of this series, the authors derived an expression for the interaction energy between two reagents in terms of the chemical reactivity indicators that can be derived from density functional perturbation theory. While negative interaction energies can explain reactivity, reactivity is often more simply explained using the “|dμ| big is good” rule or the maximum hardness principle. Expressions for the change in chemical potential (μ) and hardness when two reagents interact are derived. A partial justification for the maximum hardness principle is that the terms that appear in the interaction energy expression often reappear in the expression for the interaction hardness, but with opposite sign.
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Affiliation(s)
- Ramón Alain Miranda-Quintana
- Department of Chemistry and Quantum Theory Project, University of Florida, Gainesville, FL, United States
- *Correspondence: Ramón Alain Miranda-Quintana, ; Tatiana Gómez, Carlos Cárdenas, ; Paul W. Ayers,
| | | | - Stijn Fias
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, Canada
| | - Allison E. A. Chapman
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, Canada
| | - Shubin Liu
- Research Computing Center, University of North Carolina, Chapel Hill, NC, United states
| | - Christophe Morell
- Université de Lyon, Universit́e Claude Bernard Lyon 1, Institut des Sciences Analytiques, UMR CNRS 5280, Villeurbanne Cedex, France
| | - Tatiana Gómez
- Theoretical and Computational Chemistry Center, Institute of Applied Chemical Sciences, Faculty of Engineering, Universidad Autonoma de Chile, Santiago, Chile
- *Correspondence: Ramón Alain Miranda-Quintana, ; Tatiana Gómez, Carlos Cárdenas, ; Paul W. Ayers,
| | - Carlos Cárdenas
- Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
- Centro para el desarrollo de la Nanociencias y Nanotecnologia, CEDENNA, Santiago, Chile
- *Correspondence: Ramón Alain Miranda-Quintana, ; Tatiana Gómez, Carlos Cárdenas, ; Paul W. Ayers,
| | - Paul W. Ayers
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, Canada
- *Correspondence: Ramón Alain Miranda-Quintana, ; Tatiana Gómez, Carlos Cárdenas, ; Paul W. Ayers,
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5
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Kaya S, Robles-Navarro A, Mejía E, Gómez T, Cardenas C. On the Prediction of Lattice Energy with the Fukui Potential: Some Supports on Hardness Maximization in Inorganic Solids. J Phys Chem A 2022; 126:4507-4516. [PMID: 35766899 PMCID: PMC9289887 DOI: 10.1021/acs.jpca.1c09898] [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: 11/28/2022]
Abstract
Using perturbation theory within the framework of conceptual density functional theory, we derive a lower bound for the lattice energy of the ionic solids. The main element of the lower bound is the Fukui potential in the nuclei of the molecule corresponding to the unit formula of the solid. Thus, we propose a model to calculate the lattice energy in terms of the Fukui potential. Our method, which is extremely simple, performs well as other methods using the crystal structure information of alkali halide solids. The method proposed here correlates surprisingly well with the experimental data on the lattice energy of a diverse series of solids having even a non-negligible covalent characteristic. Finally, the validity of the maximum hardness principle (MHP) is assessed, showing that in this case, the MHP is limited.
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Affiliation(s)
- Savaş Kaya
- Health Services Vocational School, Department of Pharmacy, Sivas Cumhuriyet University, Sivas58140, Turkey
| | - Andrés Robles-Navarro
- Departamento de Física, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago Casilla653, Chile
| | - Erica Mejía
- Facultad de Ingeniería-(Medellin-Colombia), Institución Universitaria Pascual Bravo, Medellín050025, Colombia
| | - Tatiana Gómez
- Theoretical and Computational Chemistry Center, Institute of Applied Chemical Sciences, Faculty of Engineering, Universidad Autonoma de Chile, Santiago9170124, Chile
| | - Carlos Cardenas
- Departamento de Física, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Santiago Casilla653, Chile.,Centro para el Desarrollo de la Nanociencia y la Nanotecnología (CEDENNA), Avda. Ecuador 3493, Santiago9170124, Chile
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6
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Miranda-Quintana RA, Heidar-Zadeh F, Fias S, Chapman AEA, Liu S, Morell C, Gómez T, Cárdenas C, Ayers PW. Molecular Interactions From the Density Functional Theory for Chemical Reactivity: The Interaction Energy Between Two-Reagents. Front Chem 2022; 10:906674. [PMID: 35769444 PMCID: PMC9234655 DOI: 10.3389/fchem.2022.906674] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 04/19/2022] [Indexed: 12/13/2022] Open
Abstract
Reactivity descriptors indicate where a reagent is most reactive and how it is most likely to react. However, a reaction will only occur when the reagent encounters a suitable reaction partner. Determining whether a pair of reagents is well-matched requires developing reactivity rules that depend on both reagents. This can be achieved using the expression for the minimum-interaction-energy obtained from the density functional reactivity theory. Different terms in this expression will be dominant in different circumstances; depending on which terms control the reactivity, different reactivity indicators will be preferred.
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Affiliation(s)
- Ramón Alain Miranda-Quintana
- Department of Chemistry and Quantum Theory Project, University of Florida, Gainesville, FL, United States
- *Correspondence: Ramón Alain Miranda-Quintana, ; Carlos Cárdenas, ; Paul W. Ayers, ; Tatiana Gómez,
| | | | - Stijn Fias
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, Canada
| | - Allison E. A. Chapman
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, Canada
| | - Shubin Liu
- Research Computing Center, University of North Carolina, Chapel Hill, NC, United States
| | - Christophe Morell
- Université de Lyon, Université Claude Bernard Lyon 1, Institut des Sciences Analytiques-UMR CNRS 5280, Villeurbanne, France
| | - Tatiana Gómez
- Theoretical and Computational Chemistry Center, Institute of Applied Chemical Sciences, Faculty of Engineering, Universidad Autonoma de Chile, Santiago, Chile
- *Correspondence: Ramón Alain Miranda-Quintana, ; Carlos Cárdenas, ; Paul W. Ayers, ; Tatiana Gómez,
| | - Carlos Cárdenas
- Departamento de Fisica, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
- Centro para el desarrollo de la Nanociencias y Nanotecnologia, CEDENNA, Santiago, Chile
- *Correspondence: Ramón Alain Miranda-Quintana, ; Carlos Cárdenas, ; Paul W. Ayers, ; Tatiana Gómez,
| | - Paul W. Ayers
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, Canada
- *Correspondence: Ramón Alain Miranda-Quintana, ; Carlos Cárdenas, ; Paul W. Ayers, ; Tatiana Gómez,
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7
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Dong J, Li R, Jiang Y, Sun F, Qu Y, Wu H. A one‐dimensional
Cd‐Eu
coordination polymer with open‐chain ether Schiff base ligand and 4,4′‐bipyridine: Synthesis, structure, luminescence property, and antioxidation activities. J CHIN CHEM SOC-TAIP 2021. [DOI: 10.1002/jccs.202100167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Jianping Dong
- School of Chemistry and Chemical Engineering Lanzhou Jiaotong University Lanzhou Gansu P.R. China
| | - Ruixue Li
- School of Chemistry and Chemical Engineering Lanzhou Jiaotong University Lanzhou Gansu P.R. China
| | - Yuxuan Jiang
- School of Chemistry and Chemical Engineering Lanzhou Jiaotong University Lanzhou Gansu P.R. China
| | - Fugang Sun
- School of Chemistry and Chemical Engineering Lanzhou Jiaotong University Lanzhou Gansu P.R. China
| | - Yao Qu
- School of Chemistry and Chemical Engineering Lanzhou Jiaotong University Lanzhou Gansu P.R. China
| | - Huilu Wu
- School of Chemistry and Chemical Engineering Lanzhou Jiaotong University Lanzhou Gansu P.R. China
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8
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Well-normalized charge-transfer models: a more general derivation of the hard/soft-acid/base principle. Theor Chem Acc 2021. [DOI: 10.1007/s00214-021-02840-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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9
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Gómez T, Fuentealba P, Robles-Navarro A, Cárdenas C. Links among the Fukui potential, the alchemical hardness and the local hardness of an atom in a molecule. J Comput Chem 2021; 42:1681-1688. [PMID: 34121207 DOI: 10.1002/jcc.26705] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/24/2021] [Accepted: 05/31/2021] [Indexed: 02/01/2023]
Abstract
This paper presents a brief summary of the difficulty that resides in the definition of the elusive concept of local chemical hardness. We argue that a definition of local hardness should be useful to a reactivity principle and not just as a mere definition. We then continue with a formal discussion about the benefits and difficulties of using the Fukui potential, which is interpreted as an alchemical derivative (alchemical hardness), as descriptor of local hardness of molecules. Computational evidence shows that the alchemical hardness is at least as good a descriptor as the combination of other two well-stabilized descriptors of local hardness, such as the Fukui function and grand canonical local hardness. Although our results are auspicious for the alchemical hardness as descriptor of local hardness, we finish by calling the attention of the community on the importance of discussing the raison d'être of a local hardness function and its main characteristics. We suggest that an axiomatic construction of local hardness could be they way of constructing a local hardness which is both useful and free of arbitrariness.
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Affiliation(s)
- Tatiana Gómez
- Theoretical and Computational Chemistry Center, Institute of Applied Chemical Sciences, Faculty of Engineering, Universidad Autonoma de Chile, Santiago, Chile
| | - Patricio Fuentealba
- Departamento de Física, Facultad de Ciencias, Universidad de Chile, Santiago, Chile.,Centro para el Desarrollo de la Nanociencia y la Nanotecnología (CEDENNA), Santiago, Chile
| | | | - Carlos Cárdenas
- Departamento de Física, Facultad de Ciencias, Universidad de Chile, Santiago, Chile.,Centro para el Desarrollo de la Nanociencia y la Nanotecnología (CEDENNA), Santiago, Chile
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10
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Kujawa J, Al-Gharabli S, Muzioł TM, Knozowska K, Li G, Dumée LF, Kujawski W. Crystalline porous frameworks as nano-enhancers for membrane liquid separation – Recent developments. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.213969] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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11
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Sheehy KJ, Bateman LM, Flosbach NT, Breugst M, Byrne PA. Competition between N and O: use of diazine N-oxides as a test case for the Marcus theory rationale for ambident reactivity. Chem Sci 2020; 11:9630-9647. [PMID: 34094230 PMCID: PMC8162281 DOI: 10.1039/d0sc02834g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 07/23/2020] [Indexed: 11/21/2022] Open
Abstract
The preferred site of alkylation of diazine N-oxides by representative hard and soft alkylating agents was established conclusively using the 1H-15N HMBC NMR technique in combination with other NMR spectroscopic methods. Alkylation of pyrazine N-oxides (1 and 2) occurs preferentially on nitrogen regardless of the alkylating agent employed, while O-methylation of pyrimidine N-oxide (3) is favoured in its reaction with MeOTf. As these outcomes cannot be explained in the context of the hard/soft acid/base (HSAB) principle, we have instead turned to Marcus theory to rationalise these results. Marcus intrinsic barriers (ΔG ‡ 0) and Δr G° values were calculated at the DLPNO-CCSD(T)/def2-TZVPPD/SMD//M06-2X-D3/6-311+G(d,p)/SMD level of theory for methylation reactions of 1 and 3 by MeI and MeOTf, and used to derive Gibbs energies of activation (ΔG ‡) for the processes of N- and O-methylation, respectively. These values, as well as those derived directly from the DFT calculations, closely reproduce the observed experimental N- vs. O-alkylation selectivities for methylation reactions of 1 and 3, indicating that Marcus theory can be used in a semi-quantitative manner to understand how the activation barriers for these reactions are constructed. It was found that N-alkylation of 1 is favoured due to the dominant contribution of Δr G° to the activation barrier in this case, while O-alkylation of 3 is favoured due to the dominant contribution of the intrinsic barrier (ΔG ‡ 0) for this process. These results are of profound significance in understanding the outcomes of reactions of ambident reactants in general.
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Affiliation(s)
- Kevin J Sheehy
- School of Chemistry, Analytical and Biological Chemistry Research Facility, University College Cork College Road Cork Ireland
| | - Lorraine M Bateman
- School of Chemistry, Analytical and Biological Chemistry Research Facility, University College Cork College Road Cork Ireland
- School of Pharmacy, University College Cork College Road Ireland
- SSPC (Synthesis and Solid State Pharmaceutical Centre) Cork Ireland
| | - Niko T Flosbach
- Department für Chemie, Universität zu Köln Greinstraße 4 50939 Köln Germany
| | - Martin Breugst
- Department für Chemie, Universität zu Köln Greinstraße 4 50939 Köln Germany
| | - Peter A Byrne
- School of Chemistry, Analytical and Biological Chemistry Research Facility, University College Cork College Road Cork Ireland
- SSPC (Synthesis and Solid State Pharmaceutical Centre) Cork Ireland
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12
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Goswami S, Singha S, Saha I, Chatterjee A, Dey SK, Gómez García CJ, Frontera A, Kumar S, Saha R. Selective Metal-Ligand Bond-Breaking Driven by Weak Intermolecular Interactions: From Metamagnetic Mn(III)-Monomer to Hexacyanoferrate(II)-Bridged Metamagnetic Mn 2Fe Trimer. Inorg Chem 2020; 59:8487-8497. [PMID: 32462868 DOI: 10.1021/acs.inorgchem.0c00909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Metal-ligand coordination interactions are usually much stronger than weak intermolecular interactions. Nevertheless, here, we show experimental evidence and theoretical confirmation of a very rare example where metal-ligand bonds dissociate in an irreversible way, helped by a large number of weak intermolecular interactions that surpass the energy of the metal-ligand bond. Thus, we describe the design and synthesis of trinuclear Mn2Fe complex {[Mn(L)(H2O)]2Fe(CN)6},2- starting from a mononuclear Mn(III)-Schiff base complex: [Mn(L)(H2O)Cl] (1) and [Fe(CN)6]4- anions. This reaction implies the dissociation of Mn(III)-Cl coordination bonds and the formation of Mn(III)-NC bonds with the help of several intermolecular interactions. Here, we present the synthesis, crystal structure, and magnetic characterization of the monomeric Mn(III) complex [Mn(L)(H2O)Cl] (1) and of compound (H3O)[Mn(L)(H2O)2]{[Mn(L)(H2O)]2Fe(CN)6}·4H2O (2) (H2L = 2,2'-((1E,1'E)-(ethane-1,2-diylbis(azaneylylidene))bis(methaneylylidene))bis(4-methoxyphenol)). Complex 1 is a monomer where the Schiff base ligand (L) is coordinated to the four equatorial positions of the Mn(III) center with a H2O molecule and a Cl- ion at the axial sites and the monomeric units are assembled by π-π and hydrogen-bonding interactions to build supramolecular dimers. The combination of [Fe(CN)6]4- with complex 1 leads to the formation of linear Mn-NC-Fe-CN-Mn trimers where two trans cyano groups of the [Fe(CN)6]4- anion replace the labile chloride from the coordination sphere of two [Mn(L)(H2O)Cl] complexes, giving rise to the linear anionic {[Mn(L)(H2O)]2Fe(CN)6}2- trimer. This Mn2Fe trimer crystallizes with an oxonium cation and a mononuclear [Mn(L)(H2O)2]+ cation, closely related to the precursor neutral complex [Mn(L)(H2O)Cl]. In compound 2, the Mn2Fe trimers are assembled by several hydrogen-bonding and π-π interactions to frame an extended structure similar to that of complex 1. Density functional theoretical (DFT) calculations at the PBE1PBE-D3/def2-TZVP level show that the bond dissociation energy (-29.3 kcal/mol) for the Mn(III)-Cl bond is smaller than the summation of all the weak intermolecular interactions (-30.1 kcal/mol). Variable-temperature magnetic studies imply the existence of weak intermolecular antiferromagnetic couplings in both compounds, which can be can cancelled with a critical field of ca. 2.0 and 2.5 T at 2 K for compounds 1 and 2, respectively. The magnetic properties of compound 1 have been fit with a simple S = 2 monomer with g = 1.959, a weak zero-field splitting (|D| = 1.23 cm-1), and a very weak intermolecular interaction (zJ = -0.03 cm-1). For compound 2, we have used a model with an S = 2 monomer with ZFS plus an S = 2 antiferromagnetically coupled dimer with g = 2.009, |D| = 1.21 cm-1, and J = -0.42 cm-1. The metamagnetic behavior of both compounds is attributed to the weak intermolecular π-π and hydrogen-bonding interactions.
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Affiliation(s)
- Somen Goswami
- Department of Physics, Jadavpur University, Jadavpur, Kolkata-700032, India
| | - Soumen Singha
- Department of Physics, Jadavpur University, Jadavpur, Kolkata-700032, India
| | - Indrajit Saha
- Department of Chemistry, RKMRC, Narendrapur-700103, WB, India
| | | | - Subrata K Dey
- Department of Chemistry, Sidho-Kanho-Birsha University, Pururlia-723104, WB, India
| | - Carlos J Gómez García
- Departamento de Química Inorgánica, CMol. Universidad de Valencia, C/José Beltrán, 2, 46980 Paterna (Valencia), Spain
| | - Antonio Frontera
- Departament de Química, Universitat de les Illes Balears, Crta. de Valldemossa km 7.5, 07122 Palma de Mallorca (Baleares), Spain
| | - Sanjay Kumar
- Department of Physics, Jadavpur University, Jadavpur, Kolkata-700032, India
| | - Rajat Saha
- Department of Physics, Jadavpur University, Jadavpur, Kolkata-700032, India.,Department of Chemistry, Kazi Nazrul University, Asansol-713340, WB, India
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13
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Bettens T, Alonso M, De Proft F, Hamlin TA, Bickelhaupt FM. Ambident Nucleophilic Substitution: Understanding Non-HSAB Behavior through Activation Strain and Conceptual DFT Analyses. Chemistry 2020; 26:3884-3893. [PMID: 31957943 PMCID: PMC7154642 DOI: 10.1002/chem.202000272] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Indexed: 01/31/2023]
Abstract
The ability to understand and predict ambident reactivity is key to the rational design of organic syntheses. An approach to understand trends in ambident reactivity is the hard and soft acids and bases (HSAB) principle. The recent controversy over the general validity of this principle prompted us to investigate the competing gas-phase SN 2 reaction channels of archetypal ambident nucleophiles CN- , OCN- , and SCN- with CH3 Cl (SN 2@C) and SiH3 Cl (SN 2@Si), using DFT calculations. Our combined analyses highlight the inability of the HSAB principle to correctly predict the reactivity trends of these simple, model reactions. Instead, we have successfully traced reactivity trends to the canonical orbital-interaction mechanism and the resulting nucleophile-substrate interaction energy. The HOMO-LUMO orbital interactions set the trend in both SN 2@C and SN 2@Si reactions. We provide simple rules for predicting the ambident reactivity of nucleophiles based on our Kohn-Sham molecular orbital analysis.
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Affiliation(s)
- Tom Bettens
- Eenheid Algemene Chemie (ALGC)Vrije Universiteit BrusselPleinlaan 21050BrusselsBelgium
| | - Mercedes Alonso
- Eenheid Algemene Chemie (ALGC)Vrije Universiteit BrusselPleinlaan 21050BrusselsBelgium
| | - Frank De Proft
- Eenheid Algemene Chemie (ALGC)Vrije Universiteit BrusselPleinlaan 21050BrusselsBelgium
| | - Trevor A. Hamlin
- Department of Theoretical ChemistryAmsterdam Institute of Molecular and Life Sciences (AIMMS)Amsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081HVAmsterdamThe Netherlands
| | - F. Matthias Bickelhaupt
- Department of Theoretical ChemistryAmsterdam Institute of Molecular and Life Sciences (AIMMS)Amsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081HVAmsterdamThe Netherlands
- Institute for Molecules and Materials (IMM)Radboud University NijmegenHeyendaalseweg 1356525AJNijmegenThe Netherlands
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14
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Geerlings P, Chamorro E, Chattaraj PK, De Proft F, Gázquez JL, Liu S, Morell C, Toro-Labbé A, Vela A, Ayers P. Conceptual density functional theory: status, prospects, issues. Theor Chem Acc 2020. [DOI: 10.1007/s00214-020-2546-7] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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15
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Franco-Pérez M. An electronic temperature definition for the reactive electronic species: Conciliating practical approaches in conceptual chemical reactivity theory with a rigorous ensemble formulation. J Chem Phys 2019; 151:074105. [PMID: 31438714 DOI: 10.1063/1.5096561] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
By working under the framework of the Helmholtz potential as a functional of the equilibrium density matrix, in this contribution, we provide theoretical evidence about a particular thermodynamic situation, where electronic species display their highest susceptibility to exchange electrons to or from surroundings. This situation is denominated as the electronic temperature condition. Neutral chemical species display their lowest possible hardness value at the electronic temperature condition, and remarkably, under this circumstance, the exchange of any amount of electronic charge will necessarily be translated into a net increase in the corresponding chemical hardness. Chemical response functions defined as partial derivatives of the Helmholtz potential with respect to the (average) number of electrons and evaluated at the electronic temperature condition provide comparable results than those obtained from the coarse quadratic approximation to the exact dependence of the electronic energy vs the number of electrons, including composite quantities as the electrophilicity index. In this context, we show that the exact Helmholtz potential dependence with respect to the number of electrons can accurately be approximated by "temperature dependent" polynomial fits (up to fourth order), evaluated at the electronic temperature condition.
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Affiliation(s)
- Marco Franco-Pérez
- Facultad de Química, Universidad Nacional Autónoma de México, Cd. Universitaria, 04510 Ciudad de México, Mexico
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The “|Δμ| big is good” rule, the maximum hardness, and minimum electrophilicity principles. Theor Chem Acc 2019. [DOI: 10.1007/s00214-019-2435-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Miranda-Quintana RA, Franco-Pérez M, Gázquez JL, Ayers PW, Vela A. Chemical hardness: Temperature dependent definitions and reactivity principles. J Chem Phys 2018; 149:124110. [DOI: 10.1063/1.5040889] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - Marco Franco-Pérez
- Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Ave. San Rafael Atlixco 186, Ciudad de México 09340, Mexico
- Departamento de Física y Química Teórica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, CP 04510 México D.F., Mexico
| | - José L. Gázquez
- Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Ave. San Rafael Atlixco 186, Ciudad de México 09340, Mexico
| | - Paul W. Ayers
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Alberto Vela
- Departamento de Química, Centro de Investigación y Estudios Avanzados, Av. Instituto Politécnico Nacional 2508, Ciudad de México 07360, Mexico
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Katti S, Her B, Srivastava AK, Taylor AB, Lockless SW, Igumenova TI. High affinity interactions of Pb 2+ with synaptotagmin I. Metallomics 2018; 10:1211-1222. [PMID: 30063057 DOI: 10.1039/c8mt00135a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Lead (Pb) is a potent neurotoxin that disrupts synaptic neurotransmission. We report that Synaptotagmin I (SytI), a key regulator of Ca2+-evoked neurotransmitter release, has two high-affinity Pb2+ binding sites that belong to its cytosolic C2A and C2B domains. The crystal structures of Pb2+-complexed C2 domains revealed that protein-bound Pb2+ ions have holodirected coordination geometries and all-oxygen coordination spheres. The on-rate constants of Pb2+ binding to the C2 domains of SytI are comparable to those of Ca2+ and are diffusion-limited. In contrast, the off-rate constants are at least two orders of magnitude smaller, indicating that Pb2+ can serve as both a thermodynamic and kinetic trap for the C2 domains. We demonstrate, using NMR spectroscopy, that population of these sites by Pb2+ ions inhibits further Ca2+ binding despite the existing coordination vacancies. Our work offers a unique insight into the bioinorganic chemistry of Pb(ii) and suggests a mechanism by which low concentrations of Pb2+ ions can interfere with the Ca2+-dependent function of SytI in the cell.
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Affiliation(s)
- Sachin Katti
- Department of Biochemistry and Biophysics, Texas A&M University, 300 Olsen Boulevard, College Station, TX 77843, USA.
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Abstract
In this work some possibilities for deriving a local electrophilicity are studied. First, we consider the original definition proposed by Chattaraj, Maiti, and Sarkar (J Phys Chem A 107:4973, 2003), in which the local electrophilicity is given by the product of the global electrophilicity, and the Fukui function for charge acceptance is derived by two different approaches, making use of the chain rule for functional derivatives. We also modify the proposals based on the electron density so as to have a definition with the same units of the original definition, which also introduces a dependence in the Fukui function for charge donation. Additionally, we also explore other possibilities using the tools of information theory and the temperature dependent reactivity indices of the density functional theory of chemical reactivity. The poor results obtained from the last two approaches lead us to conjecture that this is due to the fact that the global electrophilicity is not a derivative, like most of the other reactivity indices. The conclusion is that Chattaraj's suggestion seems to be the simplest, but at the same time a very reliable approach to this important property.
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Miranda-Quintana RA, Heidar-Zadeh F, Ayers PW. Elementary Derivation of the "|Δμ| Big Is Good" Rule. J Phys Chem Lett 2018; 9:4344-4348. [PMID: 29944379 DOI: 10.1021/acs.jpclett.8b01312] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Thirty years ago, Parr and Yang postulated that favorable chemical processes are associated with large changes in the electronic chemical potential or, equivalently, the electronegativity. They called this the "|Δμ| big is good" rule and noted that if the rule could be justified, then it "would constitute a validation of frontier theory from first principles." We provide a simple and insightful justification for the "|Δμ| big is good" rule, with special emphasis on electron-transfer reactions. Furthermore, we show that it implies Pearson's hard/soft acid/base principle mathematically and confirm this result with numerical examples. This supports Parr's intuition that many other reactivity precepts arise as corollaries to the more fundamental "|Δμ| big is good" rule. In all of this, it is essential to consider the intensive nature of the chemical potential.
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Affiliation(s)
| | - Farnaz Heidar-Zadeh
- Department of Chemistry & Chemical Biology , McMaster University , Hamilton , Ontario L8S 4M1 , Canada
- Center for Molecular Modeling , Ghent University , Technologiepark 903 , 9052 Zwijnaarde , Belgium
- Physics and Materials Science Research Unit , University of Luxembourg , L-1511 Luxembourg , Luxembourg
| | - Paul W Ayers
- Department of Chemistry & Chemical Biology , McMaster University , Hamilton , Ontario L8S 4M1 , Canada
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Miranda-Quintana RA, Ayers PW. Note: Maximum hardness and minimum electrophilicity principles. J Chem Phys 2018; 148:196101. [DOI: 10.1063/1.5033964] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - Paul W. Ayers
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4L8, Canada
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Cárdenas C, Heidar-Zadeh F, Ayers PW. Benchmark values of chemical potential and chemical hardness for atoms and atomic ions (including unstable anions) from the energies of isoelectronic series. Phys Chem Chem Phys 2018; 18:25721-25734. [PMID: 27711480 DOI: 10.1039/c6cp04533b] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present benchmark values for the electronic chemical potential and chemical hardness from reference data for ionization potentials and electron affinities. In cases where the energies needed to compute these quantities are not available, we estimate the ionization potential of the metastable (di)anions by extrapolation along the isoelectronic series, taking care to ensure that the extrapolated data satisfy reasonable intuitive rules to the maximum possible extent. We also propose suitable values for the chemical potential and chemical hardness of zero-electron species. Because the values we report are faithful to the trends in accurate data on atomic energies, we believe that our proposed values for the chemical potential and chemical hardness are ideally suited to conceptual studies of chemical trends across the periodic table. The critical nuclear charge (Z critical) of the isoelectronic series with 2 < N < 96 has also been reported for the first time.
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Affiliation(s)
- Carlos Cárdenas
- Departamento de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago 7800024, Chile. and Centro para el Desarrollo de la Nanociencia y la Nanotecnología (CEDENNA), Avda. Ecuador 3493, Santiago 9170124, Chile
| | - Farnaz Heidar-Zadeh
- Department of Chemistry & Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada and Department of Inorganic & Physical Chemistry, Ghent University, Krijgslaan 281 (S3), 9000 Gent, Belgium and Center for Molecular Modeling, Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
| | - Paul W Ayers
- Department of Chemistry & Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
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Miranda-Quintana RA, Kim TD, Cárdenas C, Ayers PW. The HSAB principle from a finite-temperature grand-canonical perspective. Theor Chem Acc 2017. [DOI: 10.1007/s00214-017-2167-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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25
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Miranda-Quintana RA, Chattaraj PK, Ayers PW. Finite temperature grand canonical ensemble study of the minimum electrophilicity principle. J Chem Phys 2017; 147:124103. [DOI: 10.1063/1.4996443] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
| | - Pratim K. Chattaraj
- Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302, India
| | - Paul W. Ayers
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario L8S 4M1, Canada
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26
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Franco-Pérez M, Gázquez JL, Ayers PW, Vela A. Thermodynamic hardness and the maximum hardness principle. J Chem Phys 2017; 147:074113. [DOI: 10.1063/1.4998701] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Marco Franco-Pérez
- Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Ciudad de México 09340, Mexico
- Department of Chemistry, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - José L. Gázquez
- Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Ciudad de México 09340, Mexico
| | - Paul W. Ayers
- Department of Chemistry, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - Alberto Vela
- Departamento de Química, Centro de Investigación y de Estudios Avanzados, Av. Instituto Politécnico Nacional 2508, Ciudad de México 07360, Mexico
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27
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Miranda-Quintana RA. Note: The minimum electrophilicity and the hard/soft acid/base principles. J Chem Phys 2017; 146:046101. [DOI: 10.1063/1.4974987] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Chi X, Yu D, Li P, Lu Q, Jiang W, Hao K. The protection effects of (1E,6E)-1,7-diphenylhepta-1,6-diene-3,5-dione, a curcumin analogue, against operative liver injury in rats. Eur J Pharm Sci 2017; 100:94-101. [PMID: 28057548 DOI: 10.1016/j.ejps.2016.12.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 12/06/2016] [Accepted: 12/31/2016] [Indexed: 12/11/2022]
Abstract
The relationship between the chemistry characteristic and the hepatoprotective effects of (1E,6E)-1,7-diphenylhepta-1,6-diene-3,5-dione (DDD), a curcumin analogue, in operative liver injury rats was investigated to reveal the mechanism of hepatic protection effects of DDD. DDD (1.2-4.8mmol/kg) was administrated 10min before reperfusion phase in hepatic ischemia-reperfusion injury (IRI) rats. DDD (4.8mmol/kg) administrated 10min before ischemia and N-acetylcysteine (NAC) (4.8mmol/kg) administrated 10min before reperfusion were included for comparative studies. The plasma liver enzyme activities, histopathological indices and markers of lipid peroxide were determined to evaluate the hepatic protection effects. Effects of DDD on succinate dehydrogenase (SDH) activity were also investigated. DDD showed dose-dependent hepatocyte protections when administrated 10min before reperfusion stages in hepatic IRI rats. DDD showed almost equivalent hepatoprotective effects when administrated 10min before ischemia phase demonstrating that DDD acted on the reperfusion stages selectively against the hepatic IRI, instead of ischemia phase. NAC was not effective against hepatic IRI when treated 10min before reperfusion because of the higher pKa of NAC. In additional, DDD had no effect on the SDH both in hepatic IRI rats and in mitochondria. In conclusion, DDD had dose-dependent hepatocyte protections in the reperfusion stages in hepatic IRI rats, while the observed hepatocyte protections of DDD did not involve SDH activities. β-Diketone structures of DDD were crucial for the hepatocyte protections. The abilities of DDD to clear up the unsaturated aldehydes related with the enolate nucleophilicity and the pKa. DDD might be a promising candidate to treat hepatic IRI.
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Affiliation(s)
- Xiaowei Chi
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China; Weifang Biomedical Innovation and Entrepreneurship Service Center, Weifang 261205, China
| | - Dan Yu
- Center for Drug Safety Evaluation and Research, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Peijing Li
- State Key Laboratory of Natural Medicines, Key Lab of Drug Metabolism & Pharmacokinetics, China Pharmaceutical University, Nanjing 210009, China
| | - Qianfeng Lu
- State Key Laboratory of Natural Medicines, Key Lab of Drug Metabolism & Pharmacokinetics, China Pharmaceutical University, Nanjing 210009, China
| | - Wenjiao Jiang
- State Key Laboratory of Natural Medicines, Key Lab of Drug Metabolism & Pharmacokinetics, China Pharmaceutical University, Nanjing 210009, China
| | - Kun Hao
- State Key Laboratory of Natural Medicines, Key Lab of Drug Metabolism & Pharmacokinetics, China Pharmaceutical University, Nanjing 210009, China.
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29
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Miranda-Quintana RA, Ayers PW. Systematic treatment of spin-reactivity indicators in conceptual density functional theory. Theor Chem Acc 2016. [DOI: 10.1007/s00214-016-1995-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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30
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Heidar Zadeh F, Fuentealba P, Cárdenas C, Ayers PW. An information-theoretic resolution of the ambiguity in the local hardness. Phys Chem Chem Phys 2014; 16:6019-26. [PMID: 24553911 DOI: 10.1039/c3cp52906a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A definition of the local hardness, suitable for application in the local hard/soft acid/base principle, is derived by applying information theory.
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Affiliation(s)
| | - Patricio Fuentealba
- Departamento de Física
- Facultad de Ciencias
- Universidad de Chile
- 653-Santiago, Chile
- Centro para el desarrollo de la Nanociencias y Nanotecnologia
| | - Carlos Cárdenas
- Departamento de Física
- Facultad de Ciencias
- Universidad de Chile
- 653-Santiago, Chile
- Centro para el desarrollo de la Nanociencias y Nanotecnologia
| | - Paul W. Ayers
- Dept. of Chemistry & Chemical Biology
- McMaster University
- Hamilton, Canada
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31
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Zhang M, Li T. Intermolecular interactions in organic crystals: gaining insight from electronic structure analysis by density functional theory. CrystEngComm 2014. [DOI: 10.1039/c4ce00411f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Conceptual density functional theory is exploited to extend the HSAB (hard and soft acids and bases) principle for investigating the locality and regioselectivity of intermolecular interactions in organic crystals.
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Affiliation(s)
- Mingtao Zhang
- Industrial & Physical Pharmacy
- Purdue University
- West Lafayette, USA
| | - Tonglei Li
- Industrial & Physical Pharmacy
- Purdue University
- West Lafayette, USA
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Bultinck P, Cardenas C, Fuentealba P, Johnson PA, Ayers PW. How to Compute the Fukui Matrix and Function for Systems with (Quasi-)Degenerate States. J Chem Theory Comput 2013; 10:202-10. [DOI: 10.1021/ct400874d] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Patrick Bultinck
- Ghent University, Department of Inorganic and Physical Chemistry, Krijgslaan 281 (S3), 9000 Gent, Belgium
| | - Carlos Cardenas
- Departamento
de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile and Centro para el desarrollo de la
Nanociencias y Nanotecnologia, CEDENNA,
Av. Ecuador 3493, Santiago, Chile
| | - Patricio Fuentealba
- Departamento
de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile and Centro para el desarrollo de la
Nanociencias y Nanotecnologia, CEDENNA,
Av. Ecuador 3493, Santiago, Chile
| | - Paul A. Johnson
- Dept. of Chemistry and Chemical Biology, McMaster University, Hamilton ON Canada L8S 4M1
| | - Paul W. Ayers
- Dept. of Chemistry and Chemical Biology, McMaster University, Hamilton ON Canada L8S 4M1
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