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Fu D, Habtegabir SG, Wang H, Feng S, Han Y. Understanding of protomers/deprotomers by combining mass spectrometry and computation. Anal Bioanal Chem 2023:10.1007/s00216-023-04574-1. [PMID: 36737499 DOI: 10.1007/s00216-023-04574-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/19/2023] [Accepted: 01/27/2023] [Indexed: 02/05/2023]
Abstract
Multifunctional compounds may form different prototropic isomers under different conditions, which are known as protomers/deprotomers. In biological systems, these protomer/deprotomer isomers affect the interaction modes and conformational landscape between compounds and enzymes and thus present different biological activities. Study on protomers/deprotomers is essentially the study on the acidity/basicity of each intramolecular functional group and its effect on molecular structure. In recent years, the combination of mass spectrometry (MS) and computational chemistry has been proven to be a powerful and effective means to study prototropic isomers. MS-based technologies are developed to discriminate and characterize protomers/deprotomers to provide structural information and monitor transformations, showing great superiority than other experimental methods. Computational chemistry is used to predict the thermodynamic stability of protomers/deprotomers, provide the simulated MS/MS spectra, infrared spectra, and calculate collision cross-section values. By comparing the theoretical data with the corresponding experimental results, the researchers can not only determine the protomer/deprotomer structure, but also investigate the structure-activity relationship in a given system. This review covers various MS methods and theoretical calculations and their devotion to isomer discrimination, structure identification, conformational transformation, and phase transition investigation of protomers/deprotomers.
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Affiliation(s)
- Dali Fu
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China
| | - Sara Girmay Habtegabir
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China
| | - Haodong Wang
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China
| | - Shijie Feng
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China
| | - Yehua Han
- State Key Laboratory of Heavy Oil Processing, College of Chemical Engineering and Environment, China University of Petroleum-Beijing, Beijing, 102249, People's Republic of China.
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2
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Koopman J, Grimme S. Calculation of Mass Spectra with the QCxMS Method for Negatively and Multiply Charged Molecules. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2022; 33:2226-2242. [PMID: 36343304 DOI: 10.1021/jasms.2c00209] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Analysis and validation of a mass spectrometry (MS) experiment are usually performed by comparison to reference spectra. However, if references are missing, measured spectra cannot be properly matched. To close this gap, the Quantum Chemical Mass Spectrometry (QCxMS) program has been developed. It enables fully automatic calculations of electron ionization (EI) and positive ion collision-induced dissociation (CID) mass spectra of singly charged molecular ions. In this work, the extension to negative and multiple ion charge for the CID run mode is presented. QCxMS is now capable of calculating structures carrying any charge, without the need for pretabulated fragmentation pathways or machine learning of database spectra. Mass spectra of four single negatively charged and two multiple positively charged organic ions with molecular sizes from 12 to 92 atoms were computed and compared to reference spectra. The underlying Born-Oppenheimer molecular dynamics (MD) calculations were conducted using the semiempirical quantum mechanical GFN2-xTB method, while for some small molecules, ab initio DFT-based MD simulations were performed. Detailed insights into the fragmentation pathways were gained, and the effects of the computed charge assignments on the resulting spectrum are discussed. Especially for the negative ion mode, the influence of the deprotonation site to create the anion was found to be substantial. Doubly charged fragments could successfully be calculated fully automatically for the first time, while higher charged structures introduced severe assignment problems. Overall, this extension of the QCxMS program further enhances its applicability and underlines its value as a sophisticated toolkit for CID-based tandem MS structure elucidation.
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Affiliation(s)
- Jeroen Koopman
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115Bonn, Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, University of Bonn, Beringstr. 4, 53115Bonn, Germany
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3
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Bilonda MK, Mammino L. Computational studies of biologically active alkaloids of plant origin: an overview. PHYSICAL SCIENCES REVIEWS 2020. [DOI: 10.1515/psr-2019-0132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Computational studies nowadays constitute a crucial source of information for drug development, because they provide information on many molecular properties and also enable predictions of the properties of not-yet-synthesized compounds. Alkaloids are a vast group of natural products exhibiting a variety of biological activities, many of which are interesting for drug development. On the other hand, computational studies of biologically active alkaloids have so far mostly focused on few particularly relevant or “popular” molecules, such as quinine, caffeine, or cocaine, with only few works on the other molecules. The present work offers an overview of existing computational studies on alkaloid molecules, from the earliest ones to the most recent, and considering all the theoretical approaches with which studies have been performed (both quantum mechanics and molecular dynamics). The considered studies are grouped according to their objectives and outcomes, such as conformational analysis of alkaloid molecules, effects of selected solvents on their properties, docking studies aimed at better understanding of the interactions between alkaloid molecules and biological targets, studies focusing on structure activity relationships, and computational studies performed to confirm experimental results. It is concluded that it would be important that computational studies on many other alkaloid molecules are performed and their results made available, covering their different classes as well as the variety of their biological activities, to attain better understanding of the properties not only of individual molecules, but also of groups of related molecules and of the overall alkaloids family.
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Affiliation(s)
- Mireille K. Bilonda
- School of Mathematical and Natural Sciences, University of Venda , Thohoyandou , South Africa
- Faculty of Science, University of Kinshasa , Kinshasa , Democratic Republic of Congo
| | - Liliana Mammino
- School of Mathematical and Natural Sciences, University of Venda , Thohoyandou , South Africa
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Rodríguez Ortega PG, Montejo M, Márquez F, López González JJ. Conformational properties of chiral tobacco alkaloids by DFT calculations and vibrational circular dichroism: (-)-S-anabasine. J Mol Graph Model 2015; 60:169-79. [PMID: 26059478 DOI: 10.1016/j.jmgm.2015.05.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 05/15/2015] [Accepted: 05/22/2015] [Indexed: 12/12/2022]
Abstract
A thorough DFT and MM study of the conformational landscape, molecular and electronic structures of (-)-S-anabasine is reported aimed to reveal the mechanism controlling its conformational preference. Although the conformational flexibility and diversity of this system is quite extensive, only two structures are populated both in gas-phase and solution (CCl4 and DMSO). NBO-aided electronic structure analyses performed for the eight conformers representing minima in the potential energy surface of (-)-S-anabasine indicate that both steric and electrostatic factors are determinant in the conformational distribution of the sample in gas phase. Nonetheless, hyperconjugative effects are the key force tipping the balance in the conformational equilibrium between the two main rotamers. Increasing the polarity of the medium (using the IEF-PCM formalism) barely affect the conformational energy profile, although a slight increase in the theoretical population of those structures more affected by electrostatic interactions is predicted. The validity of the theoretical models and calculated conformers populations are endorsed by the accurate reproduction of the IR and VCD spectra (recorded in pure liquid and in CCl4 solution) of the sample (that have been firstly recorded and assigned in the present work) which are consistent with the occurrence of a 2:1 conformational ratio.
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Affiliation(s)
- P G Rodríguez Ortega
- Physical and Analytical Chemistry Department, Experimental Science Faculty, University of Jaén, Campus "Las Lagunillas", Ed. B3, Jaén E-23071, Spain
| | - M Montejo
- Physical and Analytical Chemistry Department, Experimental Science Faculty, University of Jaén, Campus "Las Lagunillas", Ed. B3, Jaén E-23071, Spain.
| | - F Márquez
- Physical and Analytical Chemistry Department, Experimental Science Faculty, University of Jaén, Campus "Las Lagunillas", Ed. B3, Jaén E-23071, Spain
| | - J J López González
- Physical and Analytical Chemistry Department, Experimental Science Faculty, University of Jaén, Campus "Las Lagunillas", Ed. B3, Jaén E-23071, Spain
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5
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Rodríguez Ortega PG, Montejo M, Márquez F, López González JJ. DFT-Aided Vibrational Circular Dichroism Spectroscopy Study of (−)-S-cotinine. Chemphyschem 2015; 16:1416-27. [DOI: 10.1002/cphc.201500018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Indexed: 11/07/2022]
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6
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Yoshida T, Farone WA, Xantheas SS. Isomers and conformational barriers of gas-phase nicotine, nornicotine, and their protonated forms. J Phys Chem B 2014; 118:8273-85. [PMID: 24654683 DOI: 10.1021/jp501646p] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report extensive conformational searches of the gas-phase neutral nicotine, nornicotine, and their protonated analogs and the pathways and barriers for the interconversion between their various isomers that are based on ab initio second-order Møller-Plesset perturbation (MP2) electronic structure calculations. Initial searches were performed with the 6-31G(d,p), and the energetics of the most important structures were further refined from geometry optimizations with the larger aug-cc-pVTZ basis set. On the basis of the calculated free energies at T = 298 K for the gas-phase molecules, neutral nicotine has two dominant trans conformers, whereas neutral nornicotine is a mixture of several conformers. For nicotine, the protonation on both the pyridine and the pyrrolidine sites is energetically competitive, whereas nornicotine prefers protonation on the pyridine nitrogen. The protonated form of nicotine is mainly a mixture of two pyridine-protonated trans conformers and two pyrrolidine-protonated trans conformers, whereas the protonated form of nornicotine is a mixture of four pyridine-protonated trans conformers. Nornicotine is conformationally more flexible than nicotine; however, it is less protonated at the biologically important pyrrolidine nitrogen site. The lowest energy isomers for each case were found to interconvert via low (<6 kcal/mol) rotational barriers around the pyridine-pyrrolidine bond. These barriers are much lower than previous estimates based on lower levels of theory obtained without relaxation of the structure along the path. Nicotine was found to bind more strongly to tryptophan (Trp) than nornicotine, a finding that is consistent with nicotine's enhanced affinity in the nicotinic acetylcholide receptor.
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Affiliation(s)
- Tomoki Yoshida
- Center for Quantum Life Sciences and Department of Chemistry, Graduate School of Science, Hiroshima University , 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan
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7
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Atkinson AP, Planchat A, Graton J, Renault E, Grégoire G, Le Questel JY. Structural features and protonation site of epibatidine in the gas phase: an investigation through infrared multiphoton dissociation spectroscopy and computational chemistry. Phys Chem Chem Phys 2011; 13:2272-7. [PMID: 21135942 DOI: 10.1039/c0cp01605e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The gas phase structures of epibatidine, one of the most potent agonists of nicotinic acetylcholine receptors (nAChRs), are determined by means of infrared multiphoton dissociation (IRMPD) spectroscopy and quantum chemistry calculations. Comparison of the experimental and theoretical spectra provides evidence that about 15% of epibatidine is protonated on the Nsp(2) nitrogen in the gas phase. In contrast, the computational study of deschloroepibatidine shows that in the gas phase, the molecule is present only protonated on the Nsp(2) nitrogen. The main minima of the Nsp(2) protonated forms of the two molecules are strongly stabilized by intramolecular CH···Nsp(3) hydrogen bonds. The fundamental insights obtained in the present study on these two important nAChRs agonists show how subtle chemical modifications can have a deep impact on important physicochemical properties.
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Affiliation(s)
- Alexandre P Atkinson
- Laboratoire CEISAM, UMR CNRS 6230, Faculté des Sciences et des Techniques, Université de Nantes, 2, rue de la Houssinière, BP 92208, Nantes F-44322 Cedex 3, France
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8
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Joyce JR, Richards DS. Kinetic control of protonation in electrospray ionization. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2011; 22:360-368. [PMID: 21472595 DOI: 10.1007/s13361-010-0037-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 11/10/2010] [Accepted: 11/12/2010] [Indexed: 05/30/2023]
Abstract
The site of protonation in a molecule can greatly affect the fragments observed in product ion MS/MS spectra. In electrospray positive ionization mass spectra, protonation usually occurs predominantly on the most basic site on the molecule to produce the thermodynamically favored protonated species. However, the literature is unclear whether liquid phase or gas phase thermodynamics has the greater influence. This paper describes the protonation and fragmentation behavior of crizotinib and two of its impurities. Crizotinib has two possible protonation sites, a pyridine nitrogen and a secondary amine, piperidine nitrogen; the former is the favored site in the gas phase and the latter the more favored site in the liquid phase. The impurities contain alkyl substitution on the piperidine nitrogen, producing tertiary amine species. Literature precedence suggests that in the liquid phase, the piperidine nitrogen is still the most basic site but, in the gas phase, the pyridine nitrogen and the piperidine nitrogen have very similar basicities. Fragmentation data for the three molecules suggest that the secondary and tertiary amines protonate preferentially and almost exclusively on different sites. We propose that the secondary amine protonates on the piperidine nitrogen (influenced by solution thermodynamics) and the two tertiary amine structures protonate on the pyridine nitrogen because of steric hindrance at the most basic site of the molecule, allowing kinetic control of the protonation process.
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Affiliation(s)
- J Richard Joyce
- Pfizer Global Research and Development, Analytical Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, UK.
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9
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The Conformational Landscape of Nicotinoids: Solving the Conformational Disparity of Anabasine. Chemistry 2010; 16:10214-9. [DOI: 10.1002/chem.201000849] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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10
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Sornosa-Ten A, Albelda MT, Frías JC, García-España E, Llinares JM, Budimir A, Piantanida I. Acid-base properties of functionalised tripodal polyamines and their interaction with nucleotides and nucleic acids. Org Biomol Chem 2010; 8:2567-74. [PMID: 20485792 DOI: 10.1039/c000124d] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Novel, highly positively charged tripodal polyamines with appended heterocyclic moieties revealed an intriguing panel of protonation species within the biologically relevant range. Studied compounds bind nucleotide monophosphates by mostly electrostatic interactions but only the imidazole analogue showed selectivity toward UMP in respect to other nucleotides. Strong binding of all the studied compounds to both ds-DNA and ds-RNA is to some extent selective toward the latter, showing rather rare RNA over DNA preference.
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Affiliation(s)
- Alejandra Sornosa-Ten
- Departament de Química Inorgànica, ICMol, Facultat de Química, Universitat de València, Burjassot, Spain
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11
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Aguiar GP, Wakabayashi KAL, Luz GF, Oliveira VB, Mathias L, Vieira IJC, Braz-Filho R, Crotti AEM. Fragmentation of plumeran indole alkaloids from Aspidosperma spruceanum by electrospray ionization tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2010; 24:295-308. [PMID: 20049889 DOI: 10.1002/rcm.4389] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The fragmentation of six plumeran indole alkaloids (PIAs) previously isolated from Aspidosperma spruceanum has been investigated by electrospray ionization tandem mass spectrometry (ESI-MS/MS) in the positive ion mode. The fragmentation pathways have been established on the basis of MS/MS experiments using fragment ions generated in-source and deuterium-labeled alkaloids as precursor ions and on the basis of accurate mass measurements. Our results demonstrated that the fragmentation routes observed for the protonated PIAs are essentially derived from a pericyclic reaction and from the opening of rings D and E, followed by 1,4-hydrogen rearrangements. Product ions resulting from radical eliminations were also observed, contrary to the 'even-electron rule'. Our data reveals that some product ions from protonated PIAs provide crucial information for the characterization of the acyl substituent at N-1, the methoxyl and hydroxyl groups at the aromatic moiety, and give evidence of an ether bridge between C-18 and C-21. The data reported here were used for the dereplication of these compounds in a stem bark methanolic extract of Aspidosperma spruceanum.
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Affiliation(s)
- Gabriela P Aguiar
- Núcleo de Pesquisas em Ciências Exatas e Tecnológicas, Universidade de Franca, 14404-600 Franca-SP, Brazil
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12
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Hsu FF, Lakshmi VM, Zenser TV. Characterization of new metabolites from in vivo biotransformation of 2-amino-3-methylimidazo[4,5-f]quinoline in mouse by mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2009; 44:1359-1368. [PMID: 19629964 PMCID: PMC2832803 DOI: 10.1002/jms.1620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In studying the metabolic pathways underlying the mechanism of carcinogenesis of the heterocyclic amine of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), we recently found a new metabolite which gave an [M + H](+) ion of m/z 217 when subjected to electrospray ionization (ESI) in positive-ion mode. Following i.p. injection of this metabolite of m/z 217 (designated as m/z 217) to beta-naphthoflavone-treated mice, 57% of the total radioactivity was recovered in a 24-h mouse urine sample. HPLC separation followed by MS analysis indicates that the urine sample contained m/z 217 (36 +/- 3% of total recovered radioactivity) and two other peaks that gave rise to the [M + H](+) ions of m/z 393 (31 +/- 4%, designated as m/z 393) and m/z 233 (14 +/- 1%, designated as m/z 233). Beta-glucuronidase treatment of m/z 393 resulted in a radioactive peak corresponding to m/z 217. ESI in combination with various mass spectrometry techniques, including multiple-stage mass spectrometry, exact mass measurements and H/D exchange followed by tandem mass spectrometry, was used for structural characterization. The urinary metabolites of m/z 217, 393 and 233 were identified as 1,2-dihydro-2-amino-5-hydroxy-3-methylimidazo[4,5-f]quinoline, 1,2-dihydro-2-amino-5-O-glucuronide-3-methylimidazo[4,5-f]quinoline and 1,2-dihydro-2-amino-5,7-dihydroxy-3-methylimidazo[4,5-f]quinoline, respectively. Our results demonstrated that m/z 217 is biotransformed in vivo to m/z 393 by O-glucuronidation and to m/z 233 by oxidation. The observation of these more polar metabolites relative to IQ suggests that they may arise from a previously undescribed detoxification pathway.
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Affiliation(s)
- Fong-Fu Hsu
- Department of Medicine, Box 8127, Washington University School of Medicine, 660 S Euclid, St. Louis, Missouri 63110, USA.
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13
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Sornosa Ten A, Humbert N, Verdejo B, Llinares JM, Elhabiri M, Jezierska J, Soriano C, Kozlowski H, Albrecht-Gary AM, García-España E. Cu2+ Coordination Properties of a 2-Pyridine Heptaamine Tripod: Characterization and Binding Mechanism. Inorg Chem 2009; 48:8985-97. [DOI: 10.1021/ic9010955] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alejandra Sornosa Ten
- Laboratoire de Physico-Chimie Bioinorganique, Institut de Chimie, UMR 7177 CNRS-UdS, Université de Strasbourg, ECPM 25, rue Becquerel, 67200 Strasbourg, France
| | - Nicolas Humbert
- Laboratoire de Physico-Chimie Bioinorganique, Institut de Chimie, UMR 7177 CNRS-UdS, Université de Strasbourg, ECPM 25, rue Becquerel, 67200 Strasbourg, France
| | - Begoña Verdejo
- Instituto de Ciencia Molecular (ICMOL), Departamentos de Química Inorgánica y Orgánica, Universidad de Valencia, Edificio de Institutos, Apartado de Correos 22085, 46071 Valencia, Spain
| | - José M. Llinares
- Instituto de Ciencia Molecular (ICMOL), Departamento de Química Orgánica, Fundació General de la Universidad de Valencia, Spain
| | - Mourad Elhabiri
- Laboratoire de Physico-Chimie Bioinorganique, Institut de Chimie, UMR 7177 CNRS-UdS, Université de Strasbourg, ECPM 25, rue Becquerel, 67200 Strasbourg, France
| | - Julia Jezierska
- Faculty of Chemistry, University of Wroclaw, 14 Joliot-Curie St, 50-383 Wroclaw, Poland
| | - Conxa Soriano
- Instituto de Ciencia Molecular (ICMOL), Departamentos de Química Inorgánica y Orgánica, Universidad de Valencia, Edificio de Institutos, Apartado de Correos 22085, 46071 Valencia, Spain
| | - Henryk Kozlowski
- Faculty of Chemistry, University of Wroclaw, 14 Joliot-Curie St, 50-383 Wroclaw, Poland
| | - Anne-Marie Albrecht-Gary
- Laboratoire de Physico-Chimie Bioinorganique, Institut de Chimie, UMR 7177 CNRS-UdS, Université de Strasbourg, ECPM 25, rue Becquerel, 67200 Strasbourg, France
| | - Enrique García-España
- Instituto de Ciencia Molecular (ICMOL), Departamentos de Química Inorgánica y Orgánica, Universidad de Valencia, Edificio de Institutos, Apartado de Correos 22085, 46071 Valencia, Spain
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14
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Hu N, Tu YP, Liu Y, Jiang K, Pan Y. Dissociative Protonation and Proton Transfers: Fragmentation of α, β-Unsaturated Aromatic Ketones in Mass Spectrometry. J Org Chem 2008; 73:3369-76. [DOI: 10.1021/jo702464b] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nan Hu
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China, and Drug Metabolism and Pharmacokinetics, Genelabs Technologies, 505 Penobscot Drive, Redwood City, California 94063
| | - Ya-Ping Tu
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China, and Drug Metabolism and Pharmacokinetics, Genelabs Technologies, 505 Penobscot Drive, Redwood City, California 94063
| | - Yaqin Liu
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China, and Drug Metabolism and Pharmacokinetics, Genelabs Technologies, 505 Penobscot Drive, Redwood City, California 94063
| | - Kezhi Jiang
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China, and Drug Metabolism and Pharmacokinetics, Genelabs Technologies, 505 Penobscot Drive, Redwood City, California 94063
| | - Yuanjiang Pan
- Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China, and Drug Metabolism and Pharmacokinetics, Genelabs Technologies, 505 Penobscot Drive, Redwood City, California 94063
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15
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Seydou M, Grégoire G, Liquier J, Lemaire J, Schermann JP, Desfrançois C. Experimental Observation of the Transition between Gas-Phase and Aqueous Solution Structures for Acetylcholine, Nicotine, and Muscarine Ions. J Am Chem Soc 2008; 130:4187-95. [DOI: 10.1021/ja710040p] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Mahamadou Seydou
- Laboratoire de Physique des lasers, UMR 7538 CNRS, Université Paris 13, 93430 Villetaneuse, France, Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire UMR 7033 CNRS, Université Paris 13, 93017 Bobigny, France, and Laboratoire de Chimie Physique, UMR 8000 CNRS, Université Paris XI, Bat. 350, 91405 Orsay Cedex, France
| | - Gilles Grégoire
- Laboratoire de Physique des lasers, UMR 7538 CNRS, Université Paris 13, 93430 Villetaneuse, France, Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire UMR 7033 CNRS, Université Paris 13, 93017 Bobigny, France, and Laboratoire de Chimie Physique, UMR 8000 CNRS, Université Paris XI, Bat. 350, 91405 Orsay Cedex, France
| | - Jean Liquier
- Laboratoire de Physique des lasers, UMR 7538 CNRS, Université Paris 13, 93430 Villetaneuse, France, Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire UMR 7033 CNRS, Université Paris 13, 93017 Bobigny, France, and Laboratoire de Chimie Physique, UMR 8000 CNRS, Université Paris XI, Bat. 350, 91405 Orsay Cedex, France
| | - J. Lemaire
- Laboratoire de Physique des lasers, UMR 7538 CNRS, Université Paris 13, 93430 Villetaneuse, France, Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire UMR 7033 CNRS, Université Paris 13, 93017 Bobigny, France, and Laboratoire de Chimie Physique, UMR 8000 CNRS, Université Paris XI, Bat. 350, 91405 Orsay Cedex, France
| | - Jean Pierre Schermann
- Laboratoire de Physique des lasers, UMR 7538 CNRS, Université Paris 13, 93430 Villetaneuse, France, Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire UMR 7033 CNRS, Université Paris 13, 93017 Bobigny, France, and Laboratoire de Chimie Physique, UMR 8000 CNRS, Université Paris XI, Bat. 350, 91405 Orsay Cedex, France
| | - Charles Desfrançois
- Laboratoire de Physique des lasers, UMR 7538 CNRS, Université Paris 13, 93430 Villetaneuse, France, Laboratoire de Biophysique Moléculaire, Cellulaire et Tissulaire UMR 7033 CNRS, Université Paris 13, 93017 Bobigny, France, and Laboratoire de Chimie Physique, UMR 8000 CNRS, Université Paris XI, Bat. 350, 91405 Orsay Cedex, France
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