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Yennawar HP, Mal TK, Olsen MA, Lagalante AF, Louca EM, Gavalis AD, Silverberg LJ. Synthesis and crystal structures of two racemic 2-heteroaryl-3-phenyl-2,3-di-hydro-4 H-pyrido[3,2- e][1,3]thia-zin-4-ones. Acta Crystallogr E Crystallogr Commun 2024; 80:699-703. [PMID: 38974155 PMCID: PMC11223699 DOI: 10.1107/s2056989024005103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Accepted: 05/29/2024] [Indexed: 07/09/2024]
Abstract
3-Phenyl-2-(thio-phen-3-yl)-2,3-di-hydro-4H-pyrido[3,2-e][1,3]thia-zin-4-one (C17H12N2OS2, 1) and 2-(1H-indol-3-yl)-3-phenyl-2,3-di-hydro-4H-pyrido[3,2-e][1,3]thia-zin-4-one 0.438-hydrate (C21H15N3OS·0.438H2O, 2) crystallize in space groups P21/n and C2/c, respectively. The asymmetric unit in each case is comprised of two parent mol-ecules, albeit of mixed chirality in the case of 1 and of similar chirality in 2 with the enanti-omers occupying the neighboring asymmetric units. Structure 2 also has water mol-ecules (partial occupancies) that form continuous channels along the b -axis direction. The thia-zine rings in both structures exhibit an envelope conformation. Inter-molecular inter-actions in 1 are defined only by C-H⋯O and C-H⋯N hydrogen bonds between crystallographically independent mol-ecules. In 2, hydrogen bonds of the type N-H⋯O between independent mol-ecules and C-H⋯N(π) type, and π-π stacking inter-actions between the pyridine rings of symmetry-related mol-ecules are observed.
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Affiliation(s)
- Hemant P. Yennawar
- Department of Biochemistry and Molecular Biology Pennsylvania State University University Park PA 16802 USA
| | - Tapas K. Mal
- Department of Chemistry The Pennsylvania State University University Park PA 16802 USA
| | - Mark A. Olsen
- Mendel Science Center Villanova University, 800 Lancaster Avenue Villanova PA 19085 USA
| | - Anthony F. Lagalante
- Mendel Science Center Villanova University, 800 Lancaster Avenue Villanova PA 19085 USA
| | - Evelyn M. Louca
- Pennsylvania State University, Schuylkill Campus, 200 University Drive, Schuylkill Haven, PA 17972, USA
| | - Aloura D. Gavalis
- Pennsylvania State University, Schuylkill Campus, 200 University Drive, Schuylkill Haven, PA 17972, USA
| | - Lee J. Silverberg
- Pennsylvania State University, Schuylkill Campus, 200 University Drive, Schuylkill Haven, PA 17972, USA
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2
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Kitamura S, Lin TH, Lee CCD, Takamura A, Kadam RU, Zhang D, Zhu X, Dada L, Nagai E, Yu W, Yao Y, Sharpless KB, Wilson IA, Wolan DW. Ultrapotent influenza hemagglutinin fusion inhibitors developed through SuFEx-enabled high-throughput medicinal chemistry. Proc Natl Acad Sci U S A 2024; 121:e2310677121. [PMID: 38753503 PMCID: PMC11145270 DOI: 10.1073/pnas.2310677121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 04/19/2024] [Indexed: 05/18/2024] Open
Abstract
Seasonal and pandemic-associated influenza strains cause highly contagious viral respiratory infections that can lead to severe illness and excess mortality. Here, we report on the optimization of our small-molecule inhibitor F0045(S) targeting the influenza hemagglutinin (HA) stem with our Sulfur-Fluoride Exchange (SuFEx) click chemistry-based high-throughput medicinal chemistry (HTMC) strategy. A combination of SuFEx- and amide-based lead molecule diversification and structure-guided design led to identification and validation of ultrapotent influenza fusion inhibitors with subnanomolar EC50 cellular antiviral activity against several influenza A group 1 strains. X-ray structures of six of these compounds with HA indicate that the appended moieties occupy additional pockets on the HA surface and increase the binding interaction, where the accumulation of several polar interactions also contributes to the improved affinity. The compounds here represent the most potent HA small-molecule inhibitors to date. Our divergent HTMC platform is therefore a powerful, rapid, and cost-effective approach to develop bioactive chemical probes and drug-like candidates against viral targets.
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Affiliation(s)
- Seiya Kitamura
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA92037
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA92037
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY10461
| | - Ting-Hui Lin
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA92037
| | - Chang-Chun David Lee
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA92037
| | - Akihiro Takamura
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
| | - Rameshwar U. Kadam
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA92037
| | - Ding Zhang
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA92037
| | - Xueyong Zhu
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA92037
| | - Lucas Dada
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY10461
| | - Emiko Nagai
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY10461
| | - Wenli Yu
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA92037
| | - Yao Yao
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
| | - K. Barry Sharpless
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA92037
| | - Ian A. Wilson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA92037
- The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA92037
| | - Dennis W. Wolan
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA92037
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA92037
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3
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Chen P, Sun X, Plietker B, Ruck M. Key to High Performance Ion Hybrid Capacitor: Weakly Solvated Zinc Cations. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2305532. [PMID: 37997190 PMCID: PMC10797483 DOI: 10.1002/advs.202305532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/11/2023] [Indexed: 11/25/2023]
Abstract
Zinc ion hybrid capacitors suffer from lack of reversibility and dendrite formation. An electrolyte, based on a solution of a zinc salt in acetonitrile and tetramethylene sulfone, allows smooth zinc deposition with high coulombic efficiency in a Zn||stainless steel cell (99.6% for 2880 cycles at 1.0 mA cm-2 , 1.0 mAh cm-2 ). A Zn||Zn cell operates stably for at least 7940 h at 1.0 mA cm-2 with an area capacity of 10 mAh cm-2 , or 648 h at 90% depth of discharge and 1 mA cm-2 , 9.0 mAh cm-2 . Molecular dynamics simulations reveal the reason for the excellent reversibility: The zinc cation is only weakly solvated than in pure tetramethylene sulfone with the closest atoms at 3.3 to 3.8 Å. With this electrolyte, a zinc||activated-carbon hybrid capacitor exhibits an operating voltage of 2.0 to 2.5 V, an energy-density of 135 Wh kg-1 and a power-density of 613 W kg-1 at 0.5 A g-1 . At the very high current-density of 15 A g-1 , 29.3 Wh kg-1 and 14 250 W kg-1 are achieved with 81.2% capacity retention over 9000 cycles.
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Affiliation(s)
- Peng Chen
- Faculty of Chemistry and Food ChemistryTechnische Universität Dresden01062DresdenGermany
| | - Xiaohan Sun
- Faculty of Chemistry and Food ChemistryTechnische Universität Dresden01062DresdenGermany
| | - Bernd Plietker
- Faculty of Chemistry and Food ChemistryTechnische Universität Dresden01062DresdenGermany
| | - Michael Ruck
- Faculty of Chemistry and Food ChemistryTechnische Universität Dresden01062DresdenGermany
- Max Planck Institute for Chemical Physics of SolidsNöthnitzer Straße 4001187DresdenGermany
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4
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Saha A, Ganguly B. Exploiting the (-C-H···C-) Interaction to Design Cage-Functionalized Organic Superbases and Hyperbases: A Computational Study. ACS OMEGA 2023; 8:38546-38556. [PMID: 37867725 PMCID: PMC10586256 DOI: 10.1021/acsomega.3c05401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 09/22/2023] [Indexed: 10/24/2023]
Abstract
A set of carbon center-based P-ylidesubstituting bases have been exploited computationally with pentacyclo[5.4.0.02,6.03,10.05.9]undecane (PCU) and pentacyclo [6.4.0.02,7.03,11.06,10] dodecane (PCD) scaffolds using the B3LYP-D3/6-311+G(d,p) level of theory. The proton affinities calculated in the gas phase are in the range of superbases and hyperbases. The Atomsin-Molecules and Natural Bond Orbital calculations reveal that the -C-H···C- interaction plays a substantial role in improving the basicity, and tuning the -C-H···C- interaction can enhance the basicity of such systems. The free activation energy for proton exchange for PCD and PCU scaffolds substituted with P-ylide is substantially low. The computed results reveal the strength and nature of such - C-H···C- interactions compared to the -N-H···N- hydrogen bonds. The isodesmic reactions suggest that the superbasicity achieved using these frameworks arises from a combination of several factors, such as the ring strain of the bases in their unprotonated form, steric repulsion, and the intramolecular -C-H···C- interaction.
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Affiliation(s)
- Anusuya Saha
- Computation
and Simulation Unit, Analytical and Environmental Science Division
and Centralized Instrument Facility, CSIR-Central
Salt & Marine Chemicals Research Institute, Bhavnagar, Gujarat 364002, India
- Academy
of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Bishwajit Ganguly
- Computation
and Simulation Unit, Analytical and Environmental Science Division
and Centralized Instrument Facility, CSIR-Central
Salt & Marine Chemicals Research Institute, Bhavnagar, Gujarat 364002, India
- Academy
of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
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5
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Di Mino C, Seel AG, Clancy AJ, Headen TF, Földes T, Rosta E, Sella A, Skipper NT. Strong structuring arising from weak cooperative O-H···π and C-H···O hydrogen bonding in benzene-methanol solution. Nat Commun 2023; 14:5900. [PMID: 37736749 PMCID: PMC10516861 DOI: 10.1038/s41467-023-41451-y] [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: 11/08/2022] [Accepted: 08/30/2023] [Indexed: 09/23/2023] Open
Abstract
Weak hydrogen bonds, such as O-H···π and C-H···O, are thought to direct biochemical assembly, molecular recognition, and chemical selectivity but are seldom observed in solution. We have used neutron diffraction combined with H/D isotopic substitution to obtain a detailed spatial and orientational picture of the structure of benzene-methanol mixtures. Our analysis reveals that methanol fully solvates and surrounds each benzene molecule. The expected O-H···π interaction is highly localised and directional, with the methanol hydroxyl bond aligned normal to the aromatic plane and the hydrogen at a distance of 2.30 Å from the ring centroid. Simultaneously, the tendency of methanol to form chain and cyclic motifs in the bulk liquid is manifest in a highly templated solvation structure in the plane of the ring. The methanol molecules surround the benzene so that the O-H bonds are coplanar with the aromatic ring while the oxygens interact with C-H groups through simultaneous bifurcated hydrogen bonds. This demonstrates that weak hydrogen bonding can modulate existing stronger interactions to give rise to highly ordered cooperative structural motifs that persist in the liquid phase.
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Affiliation(s)
- Camilla Di Mino
- Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK
| | - Andrew G Seel
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK.
| | - Adam J Clancy
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Thomas F Headen
- ISIS Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot, OX11 0QX, UK
| | - Támas Földes
- Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK
| | - Edina Rosta
- Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK
| | - Andrea Sella
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
| | - Neal T Skipper
- Department of Physics and Astronomy, University College London, London, WC1E 6BT, UK.
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Jiang X, Huang B, Zalloum WA, Chen CH, Ji X, Gao Z, Dai J, Xie M, Kang D, De Clercq E, Pannecouque C, Liu X, Zhan P. Discovery of novel diarypyrimidine derivatives bearing six-membered non-aromatic heterocycles as potent HIV-1 NNRTIs with improved anti-resistance and drug-like profiles. Eur J Med Chem 2023; 258:115605. [PMID: 37393790 DOI: 10.1016/j.ejmech.2023.115605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/23/2023] [Accepted: 06/25/2023] [Indexed: 07/04/2023]
Abstract
Taking our previously reported HIV-1 NNRTIs BH-11c and XJ-10c as lead compounds, series of novel diarypyrimidine derivatives bearing six-membered non-aromatic heterocycles were designed to improve anti-resistance and drug-like profiles. According to the three rounds of in vitro antiviral activity screening, compound 12g was the most active inhibitor against wild-type and five prevalent NNRTI-resistant HIV-1 strains with EC50 values ranging from 0.024 to 0.0010 μM. This is obviously better than the lead compound BH-11c and the approved drug ETR. Detailed structure-activity relationship was investigated to provide valuable guidance for further optimization. The MD simulation study indicated that 12g could form additional interactions with residues around the binding site in HIV-1 RT, which provided reasonable explanations for its improved anti-resistance profile compared to ETR. Furthermore, 12g showed significant improvement in water solubility and other drug-like properties compared to ETR. The CYP enzymatic inhibitory assay indicated that 12g was unlikely to induce CYP-mediated drug-drug interactions. 12g pharmacokinetics parameters were investigated and it displayed a long half-life of 6.59 h in vivo. The properties of compound 12g make it a promising lead compound for the development of new generation of antiretroviral drugs.
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Affiliation(s)
- Xiangyi Jiang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Boshi Huang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Waleed A Zalloum
- Department of Pharmacy, Faculty of Health Science, American University of Madaba, P.O Box 2882, Amman, 11821, Jordan
| | - Chin-Ho Chen
- Duke University Medical Center, Box 2926, Surgical Oncology Research Facility, Durham, NC, 27710, USA
| | - Xiangkai Ji
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Zhen Gao
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Jiaojiao Dai
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Minghui Xie
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Dongwei Kang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Erik De Clercq
- Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, K.U.Leuven, Herestraat 49 Postbus 1043 (09.A097), B-3000, Leuven, Belgium
| | - Christophe Pannecouque
- Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, K.U.Leuven, Herestraat 49 Postbus 1043 (09.A097), B-3000, Leuven, Belgium
| | - Xinyong Liu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China; China-Belgium Collaborative Research Center for Innovative Antiviral Drugs of Shandong Province, 44 West Culture Road, 250012, Jinan, Shandong, PR China.
| | - Peng Zhan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China; China-Belgium Collaborative Research Center for Innovative Antiviral Drugs of Shandong Province, 44 West Culture Road, 250012, Jinan, Shandong, PR China.
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7
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Jiang X, Huang B, Rumrill S, Pople D, Zalloum WA, Kang D, Zhao F, Ji X, Gao Z, Hu L, Wang Z, Xie M, De Clercq E, Ruiz FX, Arnold E, Pannecouque C, Liu X, Zhan P. Discovery of diarylpyrimidine derivatives bearing piperazine sulfonyl as potent HIV-1 nonnucleoside reverse transcriptase inhibitors. Commun Chem 2023; 6:83. [PMID: 37120482 PMCID: PMC10148624 DOI: 10.1038/s42004-023-00888-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 04/19/2023] [Indexed: 05/01/2023] Open
Abstract
HIV-1 reverse transcriptase is one of the most attractive targets for the treatment of AIDS. However, the rapid emergence of drug-resistant strains and unsatisfactory drug-like properties seriously limit the clinical application of HIV-1 non-nucleoside reverse transcriptase inhibitors (NNRTIs). Here we show that a series of piperazine sulfonyl-bearing diarylpyrimidine-based NNRTIs were designed to improve the potency against wild-type and NNRTI-resistant strains by enhancing backbone-binding interactions. Among them, compound 18b1 demonstrates single-digit nanomolar potency against the wild-type and five mutant HIV-1 strains, which is significantly better than the approved drug etravirine. The co-crystal structure analysis and molecular dynamics simulation studies were conducted to explain the broad-spectrum inhibitory activity of 18b1 against reverse transcriptase variants. Besides, compound 18b1 demonstrates improved water solubility, cytochrome P450 liability, and other pharmacokinetic properties compared to the currently approved diarylpyrimidine (DAPY) NNRTIs. Therefore, we consider compound 18b1 a potential lead compound worthy of further study.
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Affiliation(s)
- Xiangyi Jiang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China
| | - Boshi Huang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China
| | - Shawn Rumrill
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA
| | - David Pople
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, 08854, USA
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Waleed A Zalloum
- Department of Pharmacy, Faculty of Health Science, American University of Madaba, P.O Box 2882, Amman, 11821, Jordan
| | - Dongwei Kang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China
- China-Belgium Collaborative Research Center for Innovative Antiviral Drugs of Shandong Province, 44 West Culture Road, Jinan, 250012, Shandong, PR China
| | - Fabao Zhao
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China
| | - Xiangkai Ji
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China
| | - Zhen Gao
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China
| | - Lide Hu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China
| | - Zhao Wang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China
| | - Minghui Xie
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China
| | - Erik De Clercq
- Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, K.U.Leuven, Herestraat 49 Postbus 1043 (09.A097), B-3000, Leuven, Belgium
| | - Francesc X Ruiz
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, 08854, USA.
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA.
| | - Eddy Arnold
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, 08854, USA.
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA.
| | - Christophe Pannecouque
- Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, K.U.Leuven, Herestraat 49 Postbus 1043 (09.A097), B-3000, Leuven, Belgium.
| | - Xinyong Liu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China.
- China-Belgium Collaborative Research Center for Innovative Antiviral Drugs of Shandong Province, 44 West Culture Road, Jinan, 250012, Shandong, PR China.
| | - Peng Zhan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, 44 West Culture Road, Jinan, 250012, Shandong, PR China.
- China-Belgium Collaborative Research Center for Innovative Antiviral Drugs of Shandong Province, 44 West Culture Road, Jinan, 250012, Shandong, PR China.
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8
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Villot C, Lao KU. Electronic structure theory on modeling short-range noncovalent interactions between amino acids. J Chem Phys 2023; 158:094301. [PMID: 36889981 DOI: 10.1063/5.0138032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
While short-range noncovalent interactions (NCIs) are proving to be of importance in many chemical and biological systems, these atypical bindings happen within the so-called van der Waals envelope and pose an enormous challenge for current computational methods. We introduce SNCIAA, a database of 723 benchmark interaction energies of short-range noncovalent interactions between neutral/charged amino acids originated from protein x-ray crystal structures at the "gold standard" coupled-cluster with singles, doubles, and perturbative triples/complete basis set [CCSD(T)/CBS] level of theory with a mean absolute binding uncertainty less than 0.1 kcal/mol. Subsequently, a systematic assessment of commonly used computational methods, such as the second-order Møller-Plesset theory (MP2), density functional theory (DFT), symmetry-adapted perturbation theory (SAPT), composite electronic-structure methods, semiempirical approaches, and the physical-based potentials with machine learning (IPML) on SNCIAA is carried out. It is shown that the inclusion of dispersion corrections is essential even though these dimers are dominated by electrostatics, such as hydrogen bondings and salt bridges. Overall, MP2, ωB97M-V, and B3LYP+D4 turned out to be the most reliable methods for the description of short-range NCIs even in strongly attractive/repulsive complexes. SAPT is also recommended in describing short-range NCIs only if the δMP2 correction has been included. The good performance of IPML for dimers at close-equilibrium and long-range conditions is not transferable to the short-range. We expect that SNCIAA will assist the development/improvement/validation of computational methods, such as DFT, force-fields, and ML models, in describing NCIs across entire potential energy surfaces (short-, intermediate-, and long-range NCIs) on the same footing.
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Affiliation(s)
- Corentin Villot
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, USA
| | - Ka Un Lao
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, USA
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9
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Solvation structure and dynamics of a small ion in an organic electrolyte. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2023.114666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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10
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Southern SA, Bryce DL. To what extent do bond length and angle govern the 13C and 1H NMR response to weak CH⋯O hydrogen bonds? A case study of caffeine and theophylline cocrystals. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2022; 119:101795. [PMID: 35569343 DOI: 10.1016/j.ssnmr.2022.101795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/20/2022] [Accepted: 04/21/2022] [Indexed: 06/15/2023]
Abstract
Weak hydrogen bonds are important structure-directing elements in supramolecular chemistry and biochemistry. We consider here weak CH⋯O hydrogen bonds in a series of cocrystals of theophylline and caffeine and assess to what extent the CH⋯O distance and angle govern the observed 13C and 1H isotropic chemical shifts. Gauge-including projector-augmented wave density functional theory (GIPAW DFT) calculations consistently predict a decrease in the 13C and 1H magnetic shielding constants upon hydrogen bond formation on the order of 2-5 ppm (13C) and 1-2 ppm (1H). These trends are reproduced using the machine-learning approach implemented in ShiftML. Experimental 13C and 1H chemical shifts obtained for powdered samples using one-dimensional NMR spectroscopy as well as heteronuclear correlation (HETCOR) spectroscopy correlate well with the GIPAW DFT results. However, the experimental 13C NMR response only correlates moderately well with the hydrogen bond length and angle, while the experimental 1H chemical shifts only show very weak correlations to these local structural elements. DFT computations on isolated imidazole-formaldehyde models show that the 13C and 1H chemical shifts generally decrease with the C⋯O distance but show no clear dependence on the CH⋯O angle. These results demonstrate that the 13C and 1H response to weak CH⋯O hydrogen bonding is influenced significantly by additional weak contacts within cocrystal heterodimeric units.
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Affiliation(s)
- Scott A Southern
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada
| | - David L Bryce
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada.
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11
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Gayathri V, Sheyara RTB, Devassy N, Samanta D. Investigating the degradation of
PET
utilizing
NHC
‐based catalysts and effective reuse of the degradation product as an additive with polyurethane adhesive material. J Appl Polym Sci 2022. [DOI: 10.1002/app.52474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Varnakumar Gayathri
- Polymer Science & Technology Department CSIR‐Central Leather Research Institute, Adyar Chennai India
- Academy of Scientific and Innovative Research Ghaziabad Uttar Pradesh India
| | - R. Tata Birla Sheyara
- Polymer Science & Technology Department CSIR‐Central Leather Research Institute, Adyar Chennai India
| | - Neenu Devassy
- Polymer Science & Technology Department CSIR‐Central Leather Research Institute, Adyar Chennai India
| | - Debasis Samanta
- Polymer Science & Technology Department CSIR‐Central Leather Research Institute, Adyar Chennai India
- Academy of Scientific and Innovative Research Ghaziabad Uttar Pradesh India
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12
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Gansmüller A, Mikhailov AA, Kostin GA, Raya J, Palin C, Woike T, Schaniel D. Solid-State Photo-NMR Study on Light-Induced Nitrosyl Linkage Isomers Uncovers Their Structural, Electronic, and Diamagnetic Nature. Anal Chem 2022; 94:4474-4483. [PMID: 35229596 DOI: 10.1021/acs.analchem.1c05564] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A light-induced linkage NO isomer (MS1) in trans-[Ru(15NO)(py)419F](ClO4)2 is detected and measured for the first time by solid-state MAS NMR. Chemical shift tensors of 15N and 19F, along with nJ(15N-19F) spin-spin couplings and T1 relaxation times of MS1, are compared with the ground state (GS) at temperatures T < 250 K. Isotropic chemical shifts (15N and 19F) are well resolved for two crystallographically independent cations (A and B) [Ru(15NO)(py)419F]2+, allowing to define separately both populations of MS1 isomers and thermal decay rates for two structural sites. The relaxation times T1 of 19F in the case of GS (30/38.6 s for sites A/B) and MS1 (11.6/11.8 s for sites A/B) indicate that both isomers are diamagnetic, which is the first experimental evidence of diamagnetic properties of MS1 in ruthenium nitrosyl. After light irradiation (λ = 420 nm), the NO ligand rotates by nearly 180° from F-Ru-N-O to F-Ru-O-N, whereby the isotropic chemical shifts of δiso(15N) increase and those of δiso(19F) decrease. The nJ(15N-19F) couplings increase from 2J(15N-Ru-19F)GS = 71 Hz to 3J(15N-O-Ru-19F)MS1 = 105 Hz. These results are interpreted on the basis of DFT-CASTEP calculations including Bader-, Mulliken-, and Hirshfeld-charge density distributions of both states.
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Affiliation(s)
| | - Artem A Mikhailov
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 3 Acad. Lavrentiev Avenue, 630090, Novosibirsk, Russian Federation
| | - Gennadiy A Kostin
- Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, 3 Acad. Lavrentiev Avenue, 630090, Novosibirsk, Russian Federation
| | - Jésus Raya
- Institut de Chimie de Strasbourg, UMR 7177 CNRS-Université de Strasbourg, 67000 Strasbourg, France
| | - Cyril Palin
- Université de Lorraine, CNRS, CRM2, F-54000 Nancy, France
| | - Theo Woike
- Université de Lorraine, CNRS, CRM2, F-54000 Nancy, France
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13
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Honda A, Hibi Y, Matsumoto K, Kawai M, Miyamura K. Alkyl substituent-dependent systematic change in cold crystallization of azo molecules. RSC Adv 2022; 12:7229-7236. [PMID: 35424674 PMCID: PMC8982276 DOI: 10.1039/d2ra00942k] [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] [Received: 02/13/2022] [Accepted: 02/25/2022] [Indexed: 11/21/2022] Open
Abstract
The thermal behavior of alkyl-derivatized 1-(2,4-dimethylphenylazo)-4-naphthol and 1-(2,4-dimethylphenylazo)-2-naphthol (2,4-DM-4-Cn and 2,4-DM-2-Cn, respectively) was investigated. The change in the position of the alkyl substituent led to a variation in the thermal behavior, including the cold crystallization, which is a heat-storing phenomenon. In addition, a comprehensive study of the alkyl chain length revealed that 2,4-DM-4-Cn had better crystallinity and exhibited cold crystallization with short alkyl chains. The π–π, C–H⋯N, and C–H⋯π interactions stabilized the crystal structure of 2,4-DM-4-Cn. On the other hand, the polymorphism of 2,4-DM-2-Cn inhibited the formation of a uniform crystalline phase during cooling, which led to poor crystallinity. The only difference between the compounds, the position of the substituent, resulted in a clear variation in the cold crystallization and heat storage properties. The change in alkyl substitution position and alkyl chain length of azo molecules led to the variation in cold crystallization behavior.![]()
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Affiliation(s)
- Akinori Honda
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Yukie Hibi
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Kazuma Matsumoto
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Masato Kawai
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
| | - Kazuo Miyamura
- Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan
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14
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Rees GJ, Pitak MB, Lari A, Day SP, Yates JR, Gierth P, Barnsley K, Smith ME, Coles SJ, Hanna JV, Wallis JD. Mapping of N−C Bond Formation from a Series of Crystalline Peri‐Substituted Naphthalenes by Charge Density and Solid‐State NMR Methodologies. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Gregory J. Rees
- Department of Physics University of Warwick Gibbet Hill Road Coventry CV4 7AL UK
- Department of Materials University of Oxford Parks Rd Oxford OX1 3PH UK
| | - Mateusz B. Pitak
- School of Chemistry University of Southampton Highfield Southampton SO17 1BJ UK
| | - Alberth Lari
- School of Science and Technology Nottingham Trent University Clifton Lane Nottingham NG11 8NS UK
| | - Stephen P. Day
- Department of Physics University of Warwick Gibbet Hill Road Coventry CV4 7AL UK
| | - Jonathan R. Yates
- Department of Materials University of Oxford Parks Rd Oxford OX1 3PH UK
| | | | - Kristian Barnsley
- Department of Physics University of Warwick Gibbet Hill Road Coventry CV4 7AL UK
| | - Mark E. Smith
- Vice-Chancellor's Office University of Southampton Highfield Southampton SO17 1BJ UK
| | - Simon J. Coles
- School of Chemistry University of Southampton Highfield Southampton SO17 1BJ UK
| | - John V. Hanna
- Department of Physics University of Warwick Gibbet Hill Road Coventry CV4 7AL UK
| | - John D. Wallis
- School of Science and Technology Nottingham Trent University Clifton Lane Nottingham NG11 8NS UK
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15
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Rees GJ, Pitak MB, Lari A, Day SP, Yates JR, Gierth P, Barnsley K, Smith ME, Coles SJ, Hanna JV, Wallis JD. Mapping of N-C Bond Formation from a Series of Crystalline Peri-Substituted Naphthalenes by Charge Density and Solid-State NMR Methodologies. Angew Chem Int Ed Engl 2021; 60:23878-23884. [PMID: 34464506 PMCID: PMC8596510 DOI: 10.1002/anie.202111100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Indexed: 11/21/2022]
Abstract
A combination of charge density studies and solid state nuclear magnetic resonance (NMR) 1 JNC coupling measurements supported by periodic density functional theory (DFT) calculations is used to characterise the transition from an n-π* interaction to bond formation between a nucleophilic nitrogen atom and an electrophilic sp2 carbon atom in a series of crystalline peri-substituted naphthalenes. As the N⋅⋅⋅C distance reduces there is a sharp decrease in the Laplacian derived from increasing charge density between the two groups at ca. N⋅⋅⋅C = 1.8 Å, with the periodic DFT calculations predicting, and heteronuclear spin-echo NMR measurements confirming, the 1 JNC couplings of ≈3-6 Hz for long C-N bonds (1.60-1.65 Å), and 1 JNC couplings of <1 Hz for N⋅⋅⋅C >2.1 Å.
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Affiliation(s)
- Gregory J. Rees
- Department of PhysicsUniversity of WarwickGibbet Hill RoadCoventryCV4 7ALUK
- Department of MaterialsUniversity of OxfordParks RdOxfordOX1 3PHUK
| | - Mateusz B. Pitak
- School of ChemistryUniversity of SouthamptonHighfieldSouthamptonSO17 1BJUK
| | - Alberth Lari
- School of Science and TechnologyNottingham Trent UniversityClifton LaneNottinghamNG11 8NSUK
| | - Stephen P. Day
- Department of PhysicsUniversity of WarwickGibbet Hill RoadCoventryCV4 7ALUK
| | | | | | - Kristian Barnsley
- Department of PhysicsUniversity of WarwickGibbet Hill RoadCoventryCV4 7ALUK
| | - Mark E. Smith
- Vice-Chancellor's OfficeUniversity of SouthamptonHighfieldSouthamptonSO17 1BJUK
| | - Simon J. Coles
- School of ChemistryUniversity of SouthamptonHighfieldSouthamptonSO17 1BJUK
| | - John V. Hanna
- Department of PhysicsUniversity of WarwickGibbet Hill RoadCoventryCV4 7ALUK
| | - John D. Wallis
- School of Science and TechnologyNottingham Trent UniversityClifton LaneNottinghamNG11 8NSUK
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16
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Moutzouri P, Simões de Almeida B, Torodii D, Emsley L. Pure Isotropic Proton Solid State NMR. J Am Chem Soc 2021; 143:9834-9841. [PMID: 34170672 DOI: 10.1021/jacs.1c03315] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Resolution in proton solid state magic angle sample spinning (MAS) NMR is limited by the intrinsically imperfect nature of coherent averaging induced by either MAS or multiple pulse sequence methods. Here, we suggest that instead of optimizing and perfecting a coherent averaging scheme, we could approach the problem by parametrically mapping the error terms due to imperfect averaging in a k-space representation, in such a way that they can be removed in a multidimensional correlation leaving only the desired pure isotropic signal. We illustrate the approach here by determining pure isotropic 1H spectra from a series of MAS spectra acquired at different spinning rates. For six different organic solids, the approach is shown to produce pure isotropic 1H spectra that are significantly narrower than the MAS spectrum acquired at the fastest possible rate, with linewidths down to as little as 48 Hz. On average, we observe a 7-fold increase in resolution, and up to a factor of 20, as compared with spectra acquired at 100 kHz MAS. The approach is directly applicable to a range of solids, and we anticipate that the same underlying principle for removing errors introduced here can be applied to other problems in NMR spectroscopy.
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Affiliation(s)
- Pinelopi Moutzouri
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Bruno Simões de Almeida
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Daria Torodii
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Lyndon Emsley
- Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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17
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Ghiasi R, Rahimi M. Complex formation of titanocene dichloride anticancer and Al12N12 nano-cluster: A quantum chemical investigation of solvent, temperature and pressure effects. MAIN GROUP CHEMISTRY 2021. [DOI: 10.3233/mgc-210034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This study investigated the interaction between Al12N12 nano-cluster and titanocene dichloride anticancer drug complex using B3P86 functional in gas and solution phases. Non-covalent interaction (NCI) analysis of this complex was employed for illustration of the Cl⋯Al weak non-covalent interaction. The self-consistent reaction field theory (SCRF) based on the Polarizable Continuum Model (PCM) was applied for testing the solvent effects. The solvent effect on the interaction energy, dipole moment, frontier orbital energy, and global reactivity parameters was examined as well. The changes in the dipole moment, polarizability and electronic spatial extent (ESE) with solvent polarity were analyzed by applying different solvent polarity parameters based on Lippert-Mataga, Bakhshiev and Bilot-Kawski models. In addition, temperature and pressure effects on the thermodynamic parameters of this interaction were illustrated.
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Affiliation(s)
- Reza Ghiasi
- Department of Chemistry, East Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Maryam Rahimi
- Department of chemistry, Faculty of science, Arak Branch, Islamic Azad University, Arak, Iran
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18
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Tan C, Chen Y, Peng X, Chen Z, Cai S, Cross TA, Fu R. Revealing weak histidine 15N homonuclear scalar couplings using Solid-State Magic-Angle-Spinning NMR spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 316:106757. [PMID: 32535401 PMCID: PMC7426724 DOI: 10.1016/j.jmr.2020.106757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 05/12/2020] [Accepted: 05/27/2020] [Indexed: 05/05/2023]
Abstract
The tautomeric structure and chemistry of the histidine imidazole ring play active roles in many structurally and functionally important proteins and polypeptides. While in NMR spectroscopy histidine chemical shifts (e.g. 15N, 13C, and 1H) have been commonly used to characterize the tautomeric structure, hydrogen bonding, and torsion angles, homonuclear 15N scalar couplings in histidine have rarely been reported. Here, we propose double spin-echo sequences to compare the observed signals with and without a 90° pulse between the two spin-echo periods, such that their signal ratio as a function of the echo time solely depends on homonuclear scalar couplings, allowing for measuring weak homonuclear scalar couplings without influence from transverse dephasing effects, thus capable of revealing hydrogen-bond mediated 15N-15N J-couplings that can provide direct and definitive evidence for the formation of N…H…N hydrogen-bonding associated with the imidazole ring. We used two 13C,15N labeled histidine samples recrystallized from solutions at pH 6.3 and pH 11.0 to demonstrate the feasibility of this method and reveal the existence of a weak two-bond scalar coupling between the Nδ1 and Nε2 sites in the histidine imidazole ring in three tautomeric states and the presence of a hydrogen-bond mediated scalar coupling between the Nδ1 site in the imidazole ring and the backbone Nα site in the histidine neutral τ and π states. Our results demonstrate that weak 15N homonuclear scalar couplings can be measured even when their values are less than their corresponding intrinsic natural linewidths, thus providing direct and definitive evidence for the formation of N…H…N hydrogen bonding that is associated with the histidine imidazole ring.
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Affiliation(s)
- Chunhua Tan
- National High Magnet Field Lab, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA; Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Xiamen University, Xiamen, Fujian 361005, China
| | - Yuquan Chen
- CAS Key Laboratory of Microscale Magnetic Resonance and Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China
| | - Xinhua Peng
- CAS Key Laboratory of Microscale Magnetic Resonance and Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China
| | - Zhong Chen
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Xiamen University, Xiamen, Fujian 361005, China
| | - Shuhui Cai
- Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Xiamen University, Xiamen, Fujian 361005, China
| | - Timothy A Cross
- National High Magnet Field Lab, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA; Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA
| | - Riqiang Fu
- National High Magnet Field Lab, 1800 East Paul Dirac Drive, Tallahassee, FL 32310, USA.
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