1
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Yamaguchi K, Hirata K, Ishiuchi SI, Fujii M. Ultraviolet and infrared spectra of mono-, di- and tri-hydrated clusters of protonated noradrenaline – Solvation and conformational variations. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.140014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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2
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Sanz-Novo M, León I, Alonso ER, Alonso JL. Unleashing the shape of L-DOPA at last. Phys Chem Chem Phys 2021; 24:3546-3554. [PMID: 34908061 DOI: 10.1039/d1cp05066d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Herein, we report the first rotational study of neutral L-DOPA, an extensively used supramolecular synthon and an amino acid precursor of the neurotransmitters dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline) using broadband and narrowband Fourier transform microwave spectroscopies coupled with a laser ablation vaporization system. The spectroscopic parameters derived from the analysis of the rotational spectrum conclusively identify the existence of four distinct conformers of L-DOPA in the supersonic jet, further rejecting the previously reported catechol ring-induced conformational restriction. The analysis of the 14N nuclear quadrupole coupling hyperfine structure further revealed the orientation of the N-bearing functional group, proving the existence of stabilizing N-H⋯π interactions for the observed structures.
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Affiliation(s)
- Miguel Sanz-Novo
- Espectroscopía Molecular (GEM), Edificio Quifima Laboratorios de Espectroscopía y Bioespectroscopía Unidad Asociada CSIC, Parque Científico Uva Universidad de Valladolid, Paseo de Belén 5, Valladolid 47011, Spain.
| | - Iker León
- Espectroscopía Molecular (GEM), Edificio Quifima Laboratorios de Espectroscopía y Bioespectroscopía Unidad Asociada CSIC, Parque Científico Uva Universidad de Valladolid, Paseo de Belén 5, Valladolid 47011, Spain.
| | - Elena R Alonso
- Espectroscopía Molecular (GEM), Edificio Quifima Laboratorios de Espectroscopía y Bioespectroscopía Unidad Asociada CSIC, Parque Científico Uva Universidad de Valladolid, Paseo de Belén 5, Valladolid 47011, Spain.
| | - José L Alonso
- Espectroscopía Molecular (GEM), Edificio Quifima Laboratorios de Espectroscopía y Bioespectroscopía Unidad Asociada CSIC, Parque Científico Uva Universidad de Valladolid, Paseo de Belén 5, Valladolid 47011, Spain.
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3
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Hirata K, Kasai KI, Grégoire G, Ishiuchi SI, Fujii M. Hydration-controlled excited-state relaxation in protonated dopamine studied by cryogenic ion spectroscopy. J Chem Phys 2021; 155:151101. [PMID: 34686064 DOI: 10.1063/5.0066919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ultraviolet (UV) and infrared (IR) spectra of protonated dopamine (DAH+) and its hydrated clusters DAH+(H2O)1-3 are measured by cryogenic ion spectroscopy. DAH+ monomer and hydrated clusters with up to two water molecules show a broad UV spectrum, while it turns to a sharp, well-resolved one for DAH+-(H2O)3. Excited state calculations of DAH+(H2O)3 reproduce these spectral features. The conformer-selected IR spectrum of DAH+(H2O)3 is measured by IR dip spectroscopy, and its structure is assigned with the help of quantum chemical calculations. The excited state lifetime of DAH+ is much shorter than 20 ps, the cross correlation of the ps lasers, revealing a fast relaxation dynamics. The minimal energy path along the NH → π proton transfer coordinate exhibits a low energy barrier in the monomer, while this path is blocked by the high energy barrier in DAH+(H2O)3. It is concluded that the excited state proton transfer in DAH+ is inhibited by water-insertion.
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Affiliation(s)
- Keisuke Hirata
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsu-ta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Ken-Ichi Kasai
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsu-ta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Gilles Grégoire
- Tokyo Tech World Research Hub Initiative (WRHI), Institute of Innovation Research, Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Shun-Ichi Ishiuchi
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsu-ta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Masaaki Fujii
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsu-ta-cho, Midori-ku, Yokohama 226-8503, Japan
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4
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Ishiuchi SI, Wako H, Xantheas SS, Fujii M. Probing the selectivity of Li + and Na + cations on noradrenaline at the molecular level. Faraday Discuss 2019; 217:396-413. [PMID: 31115392 DOI: 10.1039/c8fd00186c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Although several mechanisms concerning the biological function of lithium salts, drugs having tranquilizing abilities, have been proposed so far, the key mechanism for its selectivity and subsequent interaction with neurotransmitters has not been established yet. We report ultraviolet (UV) and infrared (IR) spectra under ultra-cold conditions of Li+ and Na+ complexes of noradrenaline (NAd, norepinephrine), a neurotransmitter responsible for the body's response to stress or danger, in an effort to provide a molecular level understanding of the conformational changes of NAd due to its interactions with these two cations. A detailed analysis of the IR spectra, aided by quantum chemical calculations, reveals that the Li+-noradrenaline (NAd-Li+) complex forms only an extended structure, while the NAd-Na+ and protonated (NAd-H+) complexes form both folded and extended structures. This conformational preference of the NAd-Li+ complex is further explained by considering specific conformational distributions in solution. Our results clearly discern the unique structural motifs that NAd adopts when interacting with Li+ compared with other abundant cations in the human body (Na+) and can form the basis of a molecular level understanding of the selectivity of Li+ in biological systems.
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Affiliation(s)
- Shun-Ichi Ishiuchi
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan.
| | - Hiromichi Wako
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan.
| | - Sotiris S Xantheas
- Advanced Computing, Mathematics and Data Division, Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, MS K1-83, Richland, WA 99352, USA. and Department of Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Masaaki Fujii
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259, Nagatsuta-cho, Midori-ku, Yokohama, 226-8503, Japan.
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5
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Wako H, Ishiuchi SI, Kato D, Féraud G, Dedonder-Lardeux C, Jouvet C, Fujii M. A conformational study of protonated noradrenaline by UV–UV and IR dip double resonance laser spectroscopy combined with an electrospray and a cold ion trap method. Phys Chem Chem Phys 2017; 19:10777-10785. [DOI: 10.1039/c6cp08426e] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In protonated noradrenaline, 3 folded and 2 extended conformers were identified under the ultra-cold condition.
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Affiliation(s)
- Hiromichi Wako
- Laboratory for Chemistry and Life Science
- Institute of innovative research
- Tokyo Institute of Technology
- Midori-ku
- Japan
| | - Shun-ichi Ishiuchi
- Laboratory for Chemistry and Life Science
- Institute of innovative research
- Tokyo Institute of Technology
- Midori-ku
- Japan
| | - Daichi Kato
- Laboratory for Chemistry and Life Science
- Institute of innovative research
- Tokyo Institute of Technology
- Midori-ku
- Japan
| | - Géraldine Féraud
- CNRS
- Aix-Marseille Université
- PIIM UMR 7365
- Avenue Escadrille Normandie-Niémen
- 13397 Marseille Cedex 20
| | - Claude Dedonder-Lardeux
- CNRS
- Aix-Marseille Université
- PIIM UMR 7365
- Avenue Escadrille Normandie-Niémen
- 13397 Marseille Cedex 20
| | - Christophe Jouvet
- CNRS
- Aix-Marseille Université
- PIIM UMR 7365
- Avenue Escadrille Normandie-Niémen
- 13397 Marseille Cedex 20
| | - Masaaki Fujii
- Laboratory for Chemistry and Life Science
- Institute of innovative research
- Tokyo Institute of Technology
- Midori-ku
- Japan
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6
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Bouchet A, Schütz M, Chiavarino B, Crestoni ME, Fornarini S, Dopfer O. IR spectrum of the protonated neurotransmitter 2-phenylethylamine: dispersion and anharmonicity of the NH3(+)-π interaction. Phys Chem Chem Phys 2016; 17:25742-54. [PMID: 25757357 DOI: 10.1039/c5cp00221d] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The structure and dynamics of the highly flexible side chain of (protonated) phenylethylamino neurotransmitters are essential for their function. The geometric, vibrational, and energetic properties of the protonated neutrotransmitter 2-phenylethylamine (H(+)PEA) are characterized in the N-H stretch range by infrared photodissociation (IRPD) spectroscopy of cold ions using rare gas tagging (Rg = Ne and Ar) and anharmonic calculations at the B3LYP-D3/(aug-)cc-pVTZ level including dispersion corrections. A single folded gauche conformer (G) protonated at the basic amino group and stabilized by an intramolecular NH(+)-π interaction is observed. The dispersion-corrected density functional theory calculations reveal the important effects of dispersion on the cation-π interaction and the large vibrational anharmonicity of the NH3(+) group involved in the NH(+)-π hydrogen bond. They allow for assigning overtone and combination bands and explain anomalous intensities observed in previous IR multiple-photon dissociation spectra. Comparison with neutral PEA reveals the large effects of protonation on the geometric and electronic structure.
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Affiliation(s)
- Aude Bouchet
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstrasse 36, D-10623 Berlin, Germany.
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7
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Ishiuchi SI, Yamada K, Oba H, Wako H, Fujii M. Gas phase ultraviolet and infrared spectroscopy on a partial peptide of β2-adrenoceptor SIVSF-NH2 by a laser desorption supersonic jet technique. Phys Chem Chem Phys 2016; 18:23277-84. [DOI: 10.1039/c6cp04196e] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Laser desorption supersonic jet laser spectroscopy has been applied to a penta-peptide, Ser-Ile-Val-Ser-Phe-NH2 (SIVSF-NH2), which is a partial sequence of a binding site in a β2-adrenaline receptor protein.
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Affiliation(s)
- Shun-ichi Ishiuchi
- Laboratory for Chemistry and Life Science
- Institute for Innovative Research
- Tokyo Institute of Technology
- Yokohama
- Japan
| | - Kohei Yamada
- Laboratory for Chemistry and Life Science
- Institute for Innovative Research
- Tokyo Institute of Technology
- Yokohama
- Japan
| | - Hikari Oba
- Laboratory for Chemistry and Life Science
- Institute for Innovative Research
- Tokyo Institute of Technology
- Yokohama
- Japan
| | - Hiromichi Wako
- Laboratory for Chemistry and Life Science
- Institute for Innovative Research
- Tokyo Institute of Technology
- Yokohama
- Japan
| | - Masaaki Fujii
- Laboratory for Chemistry and Life Science
- Institute for Innovative Research
- Tokyo Institute of Technology
- Yokohama
- Japan
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8
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Lopes Jesus AJ, Jarmelo S, Fausto R, Reva I. Conformational preferences of 3,4-dihydroxyphenylacetic acid (DOPAC). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 140:54-64. [PMID: 25589387 DOI: 10.1016/j.saa.2014.12.078] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 11/22/2014] [Accepted: 12/17/2014] [Indexed: 06/04/2023]
Abstract
The conformational space of 3,4-dihydroxyphenylacetic acid (DOPAC), an important dopamine metabolite, has been investigated by quantum chemical methods (B3LYP and MP2, with the 6-311++G(d,p) basis set) and matrix-isolation infrared spectroscopy. Detailed analysis of the calculated potential energy surfaces of the molecule led to identification of thirteen unique conformers, all of them showing the acetic acid side chain out of the aromatic ring plane by 60-95°. According to the calculated Gibbs energies, the five lowest energy conformers make up 99.7% of the conformational mixture at 298.15K, exhibiting individual populations falling between 16% and 24%. The main conformational trends of this molecule were interpreted on the grounds of a thorough analysis of the structural parameters and by the application of the Natural Bond Orbital theory. The role of the intramolecular interactions on the relative stability and structure of the conformers was also investigated. The infrared spectrum of DOPAC was registered after isolation of its monomers in argon and xenon matrices. Only one of DOPAC forms populated in the gas phase could be trapped in both matrix gases. This result is in agreement with the predicted low energy barriers for conformational isomerization and is also supported by annealing experiments. The spectra of matrix-isolated model compounds, phenylacetic acid and catechol, were studied under the same experimental conditions. These data were used as references and assisted in the interpretation of the results obtained for DOPAC.
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Affiliation(s)
- A J Lopes Jesus
- Centre of Chemistry - Coimbra, Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal.
| | - S Jarmelo
- Centre of Chemistry - Coimbra, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
| | - R Fausto
- Centre of Chemistry - Coimbra, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
| | - I Reva
- Centre of Chemistry - Coimbra, Department of Chemistry, University of Coimbra, 3004-535 Coimbra, Portugal
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9
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Sohn WY, Ishiuchi SI, Çarçabal P, Oba H, Fujii M. UV–UV hole burning and IR dip spectroscopy of homophenylalanine by laser desorption supersonic jet technique. Chem Phys 2014. [DOI: 10.1016/j.chemphys.2014.10.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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10
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Capello MC, Broquier M, Ishiuchi SI, Sohn WY, Fujii M, Dedonder-Lardeux C, Jouvet C, Pino GA. Fast Nonradiative Decay in o-Aminophenol. J Phys Chem A 2014; 118:2056-62. [DOI: 10.1021/jp411457v] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marcela C. Capello
- Instituto
de Investigaciones en Físico Química de Córdoba
(INFIQC) CONICET, UNC. Dpto. de Fisicoquímica, Facultad de
Ciencias Químicas, Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Michel Broquier
- Centre Laser de l’Université Paris Sud (CLUPS,
LUMAT FR 2764) Bât. 106, Univ
Paris-Sud 11, 91405 Orsay Cedex, France
- Institut des Sciences Moléculaires d’Orsay (ISMO,
UMR8624 CNRS) Bât. 210, Univ
Paris-Sud 11, 91405 Orsay Cedex, France
| | - Shun-Ichi Ishiuchi
- Chemical
Resources Laboratory and Integrated Research Institute, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku,Yokohama 226-8503, Japan
| | - Woon Y. Sohn
- Chemical
Resources Laboratory and Integrated Research Institute, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku,Yokohama 226-8503, Japan
| | - Masaaki Fujii
- Chemical
Resources Laboratory and Integrated Research Institute, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku,Yokohama 226-8503, Japan
| | - Claude Dedonder-Lardeux
- Physique
des Interactions Ioniques et Moléculaires (PIIM), UMR-CNRS 7345 Aix-Marseille Université, Avenue Escadrille Normandie-Niémen, 13397 Marseille Cedex 20, France
| | - Christophe Jouvet
- Physique
des Interactions Ioniques et Moléculaires (PIIM), UMR-CNRS 7345 Aix-Marseille Université, Avenue Escadrille Normandie-Niémen, 13397 Marseille Cedex 20, France
| | - Gustavo A. Pino
- Instituto
de Investigaciones en Físico Química de Córdoba
(INFIQC) CONICET, UNC. Dpto. de Fisicoquímica, Facultad de
Ciencias Químicas, Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA Córdoba, Argentina
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11
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Ganesan A, Mohammadi N, Wang F. From building blocks of proteins to drugs: a quantum chemical study on structure–property relationships of phenylalanine, tyrosine and dopa. RSC Adv 2014. [DOI: 10.1039/c3ra47364c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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12
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Ishiuchi SI, Sone H, Fujii M. Laser Desorption Supersonic Jet Spectroscopy of Octopamine by Its Hydrochloride Salt. CHEM LETT 2013. [DOI: 10.1246/cl.130431] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
| | - Hirokazu Sone
- Chemical Resources Laboratory, Tokyo Institute of Technology
| | - Masaaki Fujii
- Chemical Resources Laboratory, Tokyo Institute of Technology
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13
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Jung HJ, Sohn WY, Heo CH, Kim HM, Ishiuchi SI, Fujii M, Kang H. Gas-Phase Spectroscopy of Laser-Desorbed Acedan and Proline-Acedan. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.8.2241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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14
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Ishiuchi SI, Yamada K, Chakraborty S, Yagi K, Fujii M. Gas-phase spectroscopy and anharmonic vibrational analysis of the 3-residue peptide Z-Pro-Leu-Gly-NH2 by the laser desorption supersonic jet technique. Chem Phys 2013. [DOI: 10.1016/j.chemphys.2012.12.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Sohn WY, Ishiuchi SI, Miyazaki M, Kang J, Lee S, Min A, Choi MY, Kang H, Fujii M. Conformationally resolved spectra of acetaminophen by UV-UV hole burning and IR dip spectroscopy in the gas phase. Phys Chem Chem Phys 2013. [PMID: 23207427 DOI: 10.1039/c2cp43552g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Electronic and vibrational spectra of acetaminophen were measured by using UV-UV hole burning (HB) and IR dip spectroscopy. HB spectra show the coexistence of 4 different species, which include two new ones. Low-frequency transitions in the spectra are reproduced by a one-dimensional periodic potential with a free-rotor basis set for the methyl group. From the analysis, we concluded that acetaminophen has two conformers and each conformer gives two independent transitions starting from the most stable 0a(1) and the hot 1e internal rotational levels. It is also found that the HB spectrum of the trans-conformer in the previous report is that from the 1e excited level, while the HB spectrum of the cis-conformer is contaminated by the transitions of the trans-conformer. Potential curves of the methyl rotational motion are determined both in S(0) and S(1).
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Affiliation(s)
- Woon Yong Sohn
- Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
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16
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Shimozono Y, Yamada K, Ishiuchi SI, Tsukiyama K, Fujii M. Revised conformational assignments and conformational evolution of tyrosine by laser desorption supersonic jet laser spectroscopy. Phys Chem Chem Phys 2013; 15:5163-75. [DOI: 10.1039/c3cp43573c] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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17
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Yamada Y, Ohba H, Noboru Y, Daicho S, Nibu Y. Solvation effect on the NH stretching vibrations of solvated aminopyrazine, 2-aminopyridine, and 3-aminopyridine clusters. J Phys Chem A 2012; 116:9271-8. [PMID: 22937786 DOI: 10.1021/jp306609f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The vibrational spectra of the hydrated and methanol-solvated aminopyrazine, 2-aminopyridine and 3-aminopyridine in supersonic jets have been measured in terms of IR-UV double-resonance spectroscopy. Comparing the IR spectrum of aminopyrazine with those of 2-aminopyridine and 3-aminopyridine clusters, we determine the solvation structure of aminopyrazine to be a similar cyclic structure as hydrated 2-aminopyridine clusters [Wu, et al., Phys. Chem. Chem. Phys. 2004, 6, 515]. In the case of monohydrated aminopyrazine cluster, one of the normal modes composed of the hydrogen-bonded OH and NH stretching local modes gives the anomalously weak IR intensity, which is ascribed to the cancellation of the dipole moment change between the OH and NH stretching local modes. The solvated 3-aminopyridine clusters forms the hydrogen-bond between the pyridyl nitrogen atom and the OH group, but the amino group is indirectly affected to induce slight blue shift of the NH(2) stretches. This phenomenon is explained by inductive effect where the electron withdrawing from the amino group upon the solvation results in a "quinoid-like" structure of the amino group.
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Affiliation(s)
- Yuji Yamada
- Department of Chemistry, Faculty of Science, Fukuoka University, Fukuoka 814-0180, Japan
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18
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Chakraborty S, Yamada K, Ishiuchi SI, Fujii M. Gas phase IR spectra of tri-peptide Z-Pro-Leu-Gly: Effect of C-terminal amide capping on secondary structure. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.01.086] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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Solvent-assisted conformational isomerization (SACI) of meta-substituted phenols: Tuning relative stability, isomerization barrier, and IVR rate. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.01.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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Miyazaki M, Makara K, Ishiuchi SI, Fujii M. Gas-phase Infrared Spectroscopy of Monopeptides from 10 to 3 µm. CHEM LETT 2011. [DOI: 10.1246/cl.2011.1157] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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21
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Ishiuchi SI, Asakawa T, Mitsuda H, Miyazaki M, Chakraborty S, Fujii M. Gas-phase spectroscopy of synephrine by laser desorption supersonic jet technique. J Phys Chem A 2011; 115:10363-9. [PMID: 21819118 DOI: 10.1021/jp205267c] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In our previous work, we found that synephrine has six conformers in the gas phase, while adrenaline, which is a catecholamine and has the same side chain as synephrine, has been reported to have only two conformers. To determine the conformational geometries of synephrine, we measured resonance enhanced multiphoton ionization, ultraviolet-ultraviolet hole burning, and infrared dip spectra by utilizing the laser desorption supersonic jet technique. By comparing the observed infrared spectra with theoretical ones, we assigned geometries except for the orientations of the phenolic OH group. Comparison between the determined structures of synephrine and those of 2-methylaminno-1-phenylethanol, which has the same side chain as synephrine but no phenol OH group, leads to the conclusion that the phenolic OH group in synephrine does not affect the conformational flexibility of the side chain. In the case of adrenaline, which is expected to have 12 conformers if there are no interactions between the catecholic OH groups and the side chain, some interactions possibly exist between them because only two conformations are observed. By estimation of the dipole-dipole interaction energy between partial dipole moments of the catecholic OH groups and the side chain, it was concluded that the dipole-dipole interaction stabilizes specific conformers which are actually observed.
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Affiliation(s)
- Shun-ichi Ishiuchi
- Chemical Resources Laboratory, Tokyo Institute of Technology, 4259, Yokahama 226-8503, Japan
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