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Mandai H, Matsuura Y, Johari FMB, Mitsudo K, Suga S. An Efficient Protocol for Selective Silylation of Hydroxy Group Using N, O-Bis( tert-butyldimethylsilyl)acetamide and N, N-Dimethyl-4-aminopyridine N-oxide. CHEM LETT 2022. [DOI: 10.1246/cl.220281] [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)
- Hiroki Mandai
- Department of Pharmacy, Faculty of Pharmacy, Gifu University of Medical Science, 4-3-3 Nijigaoka, Kani, Gifu, 509-0293
| | - Yuichiro Matsuura
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka Kita-ku, Okayama 700-8530
| | - Fatin Mahfuzah Binti Johari
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka Kita-ku, Okayama 700-8530
| | - Koichi Mitsudo
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka Kita-ku, Okayama 700-8530
| | - Seiji Suga
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka Kita-ku, Okayama 700-8530
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2
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On the Protonation and Deuteration of Simple Phenols**. ChemistrySelect 2022. [DOI: 10.1002/slct.202201083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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3
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Lysova SS, Skripnikova TA, Zevatsky YE. Algorithm for Calculating the Protolytic Equilibrium Constants of Organic Acids in Isopropyl Alcohol. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2021. [DOI: 10.1134/s0036024421090144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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4
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Enhancement of the Antioxidant and Antimicrobial Activities of Porphyran through Chemical Modification with Tyrosine Derivatives. Molecules 2021; 26:molecules26102916. [PMID: 34068969 PMCID: PMC8156949 DOI: 10.3390/molecules26102916] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 04/30/2021] [Accepted: 05/06/2021] [Indexed: 12/28/2022] Open
Abstract
The chemical modification of porphyran hydrocolloid is attempted, with the objective of enhancing its antioxidant and antimicrobial activities. Sulfated galactan porphyran is obtained from commercial samples of the red algae Porphyra dioica using Soxhlet extraction with water at 100 °C and precipitation with isopropyl alcohol. The extracted porphyran is then treated with modified L-tyrosines in aqueous medium in the presence of NaOH, at ca. 70 °C. The modified tyrosines L1 and L2 are prepared through a Mannich reaction with either thymol or 2,4-di-tert-butylphenol, respectively. While the reaction with 2,4-di-tert-butylphenol yields the expected tyrosine derivative, a mixture of products is obtained with thymol. The resulting polysaccharides are structurally characterized and the respective antioxidant and antimicrobial activities are determined. Porphyran treated with the N-(2-hydroxy-3,5-di-tert-butyl-benzyl)-L-tyrosine derivative, POR-L2, presents a noticeable superior radical scavenging and antioxidant activity compared to native porphyran, POR. Furthermore, it exhibited some antimicrobial activity against S. aureus. The surface morphology of films prepared by casting with native and modified porphyrans is studied by SEM/EDS. Both POR and POR-L2 present potential applicability in the production of films and washable coatings for food packaging with improved protecting characteristics.
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Pantoja‐Hernández MA, Alemán‐Vilis JA, Sánchez A, Salas‐Reyes M, López‐Bonilla J, Matus MH, Domínguez Z. Effect of 1‐ethyl‐3‐methylimidazolium acetate on the oxidation of caffeic acid benzyl ester: An electrochemical and theoretical study. J PHYS ORG CHEM 2019. [DOI: 10.1002/poc.4044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
| | - Josué A. Alemán‐Vilis
- Unidad de Servicios de Apoyo en Resolución AnalíticaUniversidad Veracruzana Xalapa Mexico
| | - Analilia Sánchez
- Unidad de Servicios de Apoyo en Resolución AnalíticaUniversidad Veracruzana Xalapa Mexico
| | - Magali Salas‐Reyes
- Unidad de Servicios de Apoyo en Resolución AnalíticaUniversidad Veracruzana Xalapa Mexico
| | - Judith López‐Bonilla
- Unidad de Servicios de Apoyo en Resolución AnalíticaUniversidad Veracruzana Xalapa Mexico
| | - Myrna H. Matus
- Unidad de Servicios de Apoyo en Resolución AnalíticaUniversidad Veracruzana Xalapa Mexico
| | - Zaira Domínguez
- Unidad de Servicios de Apoyo en Resolución AnalíticaUniversidad Veracruzana Xalapa Mexico
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Lu J, Lu T, Zhao X, Chen X, Zhan CG. Correlations between the 1H NMR chemical shieldings and the pK a values of organic acids and amines. J Mol Model 2018; 24:146. [PMID: 29858663 DOI: 10.1007/s00894-018-3690-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 05/22/2018] [Indexed: 01/18/2023]
Abstract
The acid dissociation constants and 1H NMR chemical shieldings of organic compounds are important properties that have attracted much research interest. However, few studies have explored the relationship between these two properties. In this work, we theoretically studied the NMR chemical shifts of a series of carboxylic acids and amines in the gas phase and in aqueous solution. It was found that the negative logarithms of the experimental acid dissociation constants (i.e., the pKa values) of the organic acids and amines in aqueous solution correlate almost linearly with the corresponding calculated NMR chemical shieldings. Key factors that affect the theoretically predicted pKa values are discussed in this paper. The present work provides a new way to predict the pKa values of organic/biochemical compounds. Graphical abstract The chemical shielding values of organic acids and amines correlate near linearly with their corresponding pKa values.
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Affiliation(s)
- Juanfeng Lu
- College of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan, 430074, People's Republic of China
| | - Tingting Lu
- College of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan, 430074, People's Republic of China
| | - Xinyun Zhao
- College of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan, 430074, People's Republic of China
| | - Xi Chen
- College of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan, 430074, People's Republic of China.
| | - Chang-Guo Zhan
- College of Pharmacy, University of Kentucky, Lexington, KY, 40536, USA
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7
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Danjo H, Hamaguchi M, Asai K, Nakatani M, Kawanishi H, Kawahata M, Yamaguchi K. Proton-Induced Assembly–Disassembly Modulation of Spiroborate Twin-Bowl Polymers Bearing Pyridyl Groups. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b01924] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | | | | | - Masatoshi Kawahata
- Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan
| | - Kentaro Yamaguchi
- Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan
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Ingavat N, Kavran JM, Sun Z, Rokita SE. Active Site Binding Is Not Sufficient for Reductive Deiodination by Iodotyrosine Deiodinase. Biochemistry 2017; 56:1130-1139. [PMID: 28157283 PMCID: PMC5330855 DOI: 10.1021/acs.biochem.6b01308] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The minimal requirements for substrate recognition and turnover by iodotyrosine deiodinase were examined to learn the basis for its catalytic specificity. This enzyme is crucial for iodide homeostasis and the generation of thyroid hormone in chordates. 2-Iodophenol binds only very weakly to the human enzyme and is dehalogenated with a kcat/Km that is more than 4 orders of magnitude lower than that for iodotyrosine. This discrimination likely protects against a futile cycle of iodinating and deiodinating precursors of thyroid hormone biosynthesis. Surprisingly, a very similar catalytic selectivity was expressed by a bacterial homologue from Haliscomenobacter hydrossis. In this example, discrimination was not based on affinity since 4-cyano-2-iodophenol bound to the bacterial deiodinase with a Kd lower than that of iodotyrosine and yet was not detectably deiodinated. Other phenols including 2-iodophenol were deiodinated but only very inefficiently. Crystal structures of the bacterial enzyme with and without bound iodotyrosine are nearly superimposable and quite similar to the corresponding structures of the human enzyme. Likewise, the bacterial enzyme is activated for single electron transfer after binding to the substrate analogue fluorotyrosine as previously observed with the human enzyme. A cocrystal structure of bacterial deiodinase and 2-iodophenol indicates that this ligand stacks on the active site flavin mononucleotide (FMN) in a orientation analogous to that of bound iodotyrosine. However, 2-iodophenol association is not sufficient to activate the FMN chemistry required for catalysis, and thus the bacterial enzyme appears to share a similar specificity for halotyrosines even though their physiological roles are likely very different from those in humans.
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Affiliation(s)
- Nattha Ingavat
- Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218 United States
| | - Jennifer M. Kavran
- Department of Biochemistry and Molecular Biology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street Baltimore, Maryland 21205 United States,Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, 925 North Wolfe Street Baltimore, Maryland, 21205 United States
| | - Zuodong Sun
- Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218 United States
| | - Steven E. Rokita
- Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218 United States,Corresponding Author:
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Yu HZ, Yang YM, Zhang L, Dang ZM, Hu GH. Quantum-Chemical Predictions of pKa’s of Thiols in DMSO. J Phys Chem A 2014; 118:606-22. [DOI: 10.1021/jp410274n] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Hai-Zhu Yu
- Department
of Polymer Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Yi-Meng Yang
- Department
of Polymer Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Liang Zhang
- Department
of Polymer Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Zhi-Min Dang
- Department
of Polymer Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Guo-Hua Hu
- Laboratory of Reactions and Process Engineering (CNRS UMR 7274), CNRS-Université de Lorraine , ENSIC, 1 rue Grandville, BP 20451, 54001 Nancy, France
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