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Port-Lougarre Y, Gourlaouen C, Vileno B, Giménez-Arnau E. Antioxidant Activity and Skin Sensitization of Eugenol and Isoeugenol: Two Sides of the Same Coin? Chem Res Toxicol 2023; 36:1804-1813. [PMID: 37922503 DOI: 10.1021/acs.chemrestox.3c00263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2023]
Abstract
Eugenol and isoeugenol are well acknowledged to possess antioxidant and thus cytoprotective activities. Yet both compounds are also important skin sensitizers, compelling the cosmetics and fragrance industries to notify their presence in manufactured products. While they are structurally very similar, they show significant differences in their sensitization properties. Consequently, eugenol and isoeugenol have been the subject of many mechanistic studies where the final oxidation forms, electrophilic ortho-quinone and quinone methide, are blamed as the reactive species forming an antigenic complex with nucleophilic residues of skin proteins, inducing skin sensitization. However, radical mechanisms could compete with such an electrophilic-nucleophilic pathway. The antioxidant activity results from neutralizing reactive oxygen radicals by the release of the phenolic hydrogen atom. The so-formed phenoxyl radicals can then fully delocalize upon the structure, becoming potentially reactive toward skin proteins at several positions. To obtain in-depth insights into such reactivity, we investigated in situ the formation of radicals from eugenol and isoeugenol using electron paramagnetic resonance combined with spin trapping in reconstructed human epidermis (RHE), mimicking human skin and closer to what may happen in vivo. Two modes of radical initiation were used, exposing RHE to (i) horseradish peroxidase (HRP), complementing RHE metabolic capacities, and mimicking peroxidases present in vivo or (ii) solar light using a AM 1.5 solar simulator. In both experimental approaches, where the antioxidant character of both compounds is revealed, oxygen- and carbon-centered radicals were formed in RHE. Our hypothesis is that such carbon radicals are relevant candidates to form antigenic entities prior to conversion into electrophilic quinones. On this basis, these studies suggest that pro- or prehapten fingerprints could be advanced depending on the radical initiation method. The introduction of HRP suggested that eugenol and isoeugenol behave as prohaptens, while when exposed to light, a prehapten nature could be highlighted.
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Affiliation(s)
- Yannick Port-Lougarre
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Christophe Gourlaouen
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Bertrand Vileno
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Elena Giménez-Arnau
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
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2
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Jabeen S, Ghosh G, Lapoot L, Durantini AM, Greer A. Sensitized Photooxidation of Ortho-prenyl Phenol: Biomimetic Dihydrobenzofuran Synthesis and Total 1 O 2 Quenching. Photochem Photobiol 2022; 99:637-641. [PMID: 35977738 DOI: 10.1111/php.13689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 08/05/2022] [Indexed: 11/30/2022]
Abstract
The sensitized photooxidation of ortho-prenyl phenol is described with evidence that solvent aproticity favors the formation of a dihydrobenzofuran [2-(prop-1-en-2-yl)-2,3-dihydrobenzofuran], a moiety commonly found in natural products. Benzene solvent increased the total quenching rate constant (kT ) of singlet oxygen with prenyl phenol by ~10-fold compared to methanol. A mechanism is proposed with preferential addition of singlet oxygen addition to prenyl site due to hydrogen bonding with phenol OH group, which causes a divergence away from the singlet oxygen 'ene' reaction toward the dihydrobenzofuran as the major product. The reaction is a mixed photooxidized system since an epoxide arises by a type I sensitized photooxidation.
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Affiliation(s)
- Shakeela Jabeen
- Department of Chemistry, Brooklyn College of the City University of New York, Brooklyn, New York 11210, United States.,Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
| | - Goutam Ghosh
- Department of Chemistry, Brooklyn College of the City University of New York, Brooklyn, New York 11210, United States.,Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
| | - Lloyd Lapoot
- Department of Chemistry, Brooklyn College of the City University of New York, Brooklyn, New York 11210, United States.,Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
| | - Andrés M Durantini
- Department of Chemistry, Brooklyn College of the City University of New York, Brooklyn, New York 11210, United States.,Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States.,IDAS-CONICET, Departamento de Química, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nac. 36 Km 601, X5804BYA Río Cuarto, Córdoba, Argentina
| | - Alexander Greer
- Department of Chemistry, Brooklyn College of the City University of New York, Brooklyn, New York 11210, United States.,Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States.,Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
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3
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Patel RI, Sharma A, Sharma S, Sharma A. Visible light-mediated applications of methylene blue in organic synthesis. Org Chem Front 2021. [DOI: 10.1039/d0qo01182g] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review presents the manipulation of methylene blue in visible-light-assisted organic synthesis.
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Affiliation(s)
| | - Anoop Sharma
- Department of Chemistry
- Indian Institute of Technology Roorkee
- Roorkee-247667
- India
| | - Shivani Sharma
- Department of Chemistry
- Indian Institute of Technology Roorkee
- Roorkee-247667
- India
| | - Anuj Sharma
- Department of Chemistry
- Indian Institute of Technology Roorkee
- Roorkee-247667
- India
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4
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Turque O, Greer A, Wauchope OR. Synthetic feasibility of oxygen-driven photoisomerizations of alkenes and polyenes. Org Biomol Chem 2020; 18:9181-9190. [PMID: 33155598 DOI: 10.1039/d0ob01993c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This review describes O2-dependent photoreactions for possible routes to double-bond isomerizations. E,Z-isomerizations triggered by O2 and visible light are a new area of potential synthetic interest. The reaction involves the reversible addition of O2 to form a peroxy intermediate with oxygen evolution and partial regeneration of the compound as its isomer. Targeting of O2-dependent photoisomerizations also relates to a practical use of visible light, for example the improved light penetration depth for visible as opposed to UV photons in batch sensitized reactions. This review is intended to draw a link between visible-light formation of a peroxy intermediate and its dark degradation with O2 release for unsaturated compound isomerization. This review should be of interest both to photochemists and synthetic organic chemists, as it ties together mechanistic and synthetic work, drawing attention to an overlooked subject.
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Affiliation(s)
- Oliver Turque
- Department of Chemistry, Brooklyn College, City University of New York, Brooklyn, New York 11210, USA.
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5
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Ahn J, Avonto C, Chittiboyina AG, Khan IA. Is Isoeugenol a Prehapten? Characterization of a Thiol-Reactive Oxidative Byproduct of Isoeugenol and Potential Implications for Skin Sensitization. Chem Res Toxicol 2020; 33:948-954. [PMID: 32119530 DOI: 10.1021/acs.chemrestox.9b00501] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Isoeugenol is widely used by the cosmetic and fragrance industries, but it also represents a known cause of skin sensitization adverse effects. Although devoid of a structural alert, isoeugenol has been classified as prehapten in virtue of the presence of a pre-Michael acceptor domain. Isoeugenol oxidation could theoretically lead to the generation of reactive toxic quinones, and photoinduced oxidative degradation of isoeugenol was reported to generate strongly thiol reactive byproducts. Nonetheless, the isoeugenol degradation product responsible for increased reactivity was found to be elusive. In the present study, an aged isoeugenol sample was subjected to reactivity-guided experiments to trap elusive thiol reactive species with a fluorescent nucleophile, viz. dansyl cysteamine (DCYA). The results herein presented demonstrate that photo-oxidation of isoeugenol led to the formation of a dimeric 7,4'-oxyneolignan with strong chemical reactivity, capable of nucleophilic substitution with thiols. The results were confirmed by isolation, structural characterization, and further NMR reactivity studies. Isoeugenol is already well-known as moderately reactive in thiol depletion assays, and was herein demonstrated to be capable of converting to more potent electrophilic species upon degradation, thus acting as a prehapten. The application of the reactivity-guided strategy described herein was shown to serve as an effective tool to investigate elusive skin sensitizers.
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Affiliation(s)
- Jongmin Ahn
- National Center for Natural Products Research, Research Institute of Pharmaceutical Science, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Cristina Avonto
- National Center for Natural Products Research, Research Institute of Pharmaceutical Science, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Amar G Chittiboyina
- National Center for Natural Products Research, Research Institute of Pharmaceutical Science, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
| | - Ikhlas A Khan
- National Center for Natural Products Research, Research Institute of Pharmaceutical Science, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States.,Division of Pharmacognosy, Department of BioMolecular Sciences, School of Pharmacy, The University of Mississippi, University, Mississippi 38677, United States
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6
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Prats-Mateu B, Bock P, Schroffenegger M, Toca-Herrera JL, Gierlinger N. Following laser induced changes of plant phenylpropanoids by Raman microscopy. Sci Rep 2018; 8:11804. [PMID: 30087373 PMCID: PMC6081397 DOI: 10.1038/s41598-018-30096-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 07/24/2018] [Indexed: 12/26/2022] Open
Abstract
Raman microscopy is a powerful imaging technique for biological materials providing information about chemistry in context with microstructure. A 532 nm laser is often used as excitation source, because high spatial resolution and signal intensity can be achieved. The latter can be controlled by laser power and integration time, whereby high power and long times give good signal to noise ratio. However, most biological materials absorb in the VIS range and fluorescence masking the signal or even sample degradation might be hindering. Here, we show that on lignified plant cell walls even very short integration times and low laser powers induce a change in the ratio of the lignin bands at 1660 and 1600 cm-1. Time series on lignin model compounds revealed this change only in aromatic molecules with two OH-groups, such as coniferyl alcohol. Therefore, we conclude that monolignols are present in the cell wall and responsible for the observed effect. The solvent selectivity of the changes points to a laser induced polymerization process. The results emphasize how crucial careful adjustment of experimental parameters in Raman imaging of biological materials is and show the potential of time series and repeated imaging to get additional insights (e.g. monolignols).
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Affiliation(s)
- Batirtze Prats-Mateu
- Institute for Biophysics, Department of Nanobiotechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 11/II, 1190, Vienna, Austria
| | - Peter Bock
- Institute for Biophysics, Department of Nanobiotechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 11/II, 1190, Vienna, Austria
| | - Martina Schroffenegger
- Institute of Biologically inspired materials, Department of Nanobiotechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 11/II, 1190, Vienna, Austria
| | - José Luis Toca-Herrera
- Institute for Biophysics, Department of Nanobiotechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 11/II, 1190, Vienna, Austria
| | - Notburga Gierlinger
- Institute for Biophysics, Department of Nanobiotechnology, BOKU-University of Natural Resources and Life Sciences, Muthgasse 11/II, 1190, Vienna, Austria.
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7
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Thomsen BR, Taylor R, Madsen R, Hyldig G, Blenkiron P, Jacobsen C. Investigation of Lipid Oxidation in the Raw Materials of a Topical Skin Formulation: A Topical Skin Formulation Containing a High Lipid Content. J AM OIL CHEM SOC 2018. [DOI: 10.1002/aocs.12015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Birgitte R. Thomsen
- Bioactive Group, Division of Food Technology; National Food Institute, Technical University of Denmark, Kemitorvet building 202; 2800 Kgs Lyngby Denmark
| | - Richard Taylor
- Skin health R&D; Glaxo Smith Kline, Brentford, 980 Great West Rd; London TW8 9GS UK
| | - Robert Madsen
- Department of Chemistry; Technical University of Denmark, Kemitorvet Building 206; 2800 Kgs Lyngby Denmark
| | - Grethe Hyldig
- Bioactive Group, Division of Food Technology; National Food Institute, Technical University of Denmark, Kemitorvet building 202; 2800 Kgs Lyngby Denmark
| | - Peter Blenkiron
- Skin health R&D; Glaxo Smith Kline, Brentford, 980 Great West Rd; London TW8 9GS UK
| | - Charlotte Jacobsen
- Bioactive Group, Division of Food Technology; National Food Institute, Technical University of Denmark, Kemitorvet building 202; 2800 Kgs Lyngby Denmark
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8
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Jaufurally AS, Teixeira A, Hollande L, Allais F, Ducrot PH. Optimization of the Laccase-Catalyzed Synthesis of (±)-Syringaresinol and Study of its Thermal and Antiradical Activities. ChemistrySelect 2016. [DOI: 10.1002/slct.201600543] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Abdus S. Jaufurally
- Chaire Agro-Biotechnologies Industrielles (ABI); AgroParisTech; CEBB - 3 rue des Rouges Terres F-51110 Pomacle France
- Institut Jean-Pierre Bourgin, INRA; AgroParisTech, CNRS; Université Paris-Saclay; RD10 F-78026 Versailles Cedex France
| | - Andreia R. S. Teixeira
- Chaire Agro-Biotechnologies Industrielles (ABI); AgroParisTech; CEBB - 3 rue des Rouges Terres F-51110 Pomacle France
- UMR 1145 GENIAL, INRA; AgroParisTech, CNRS; Université Paris-Saclay; 1 avenue des Olympiades F-91744 Massy France
| | - Louis Hollande
- Chaire Agro-Biotechnologies Industrielles (ABI); AgroParisTech; CEBB - 3 rue des Rouges Terres F-51110 Pomacle France
- Institut Jean-Pierre Bourgin, INRA; AgroParisTech, CNRS; Université Paris-Saclay; RD10 F-78026 Versailles Cedex France
| | - Florent Allais
- Chaire Agro-Biotechnologies Industrielles (ABI); AgroParisTech; CEBB - 3 rue des Rouges Terres F-51110 Pomacle France
- UMR 782 GMPA, INRA; AgroParisTech, CNRS; Université Paris-Saclay; Avenue Lucien Brétignières F-78850 Thiverval-Grignon France
| | - Paul-Henri Ducrot
- Institut Jean-Pierre Bourgin, INRA; AgroParisTech, CNRS; Université Paris-Saclay; RD10 F-78026 Versailles Cedex France
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9
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Fink M, Trunk S, Hall M, Schwab H, Steiner K. Engineering of TM1459 from Thermotoga maritima for Increased Oxidative Alkene Cleavage Activity. Front Microbiol 2016; 7:1511. [PMID: 27713741 PMCID: PMC5031596 DOI: 10.3389/fmicb.2016.01511] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 09/09/2016] [Indexed: 11/26/2022] Open
Abstract
Oxidative cleavage of alkenes is a widely employed process allowing oxyfunctionalization to corresponding carbonyl compounds. Recently, a novel biocatalytic oxidative alkene cleavage activity on styrene derivatives was identified in TM1459 from Thermotoga maritima. In this work we engineered the enzyme by site-saturation mutagenesis of active site amino acids to increase its activity and to broaden its substrate scope. A high-throughput assay for the detection of the ketone products was successfully developed. Several variants with up to twofold improved conversion level of styrene derivatives were successfully identified. Especially, changes in or removal of the C-terminus of TM1459 increased the activity most significantly. These best variants also displayed a slightly enlarged substrate scope.
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Affiliation(s)
- Matthias Fink
- Austrian Centre of Industrial BiotechnologyGraz, Austria
| | - Sarah Trunk
- Austrian Centre of Industrial BiotechnologyGraz, Austria
| | - Mélanie Hall
- Department of Chemistry, University of GrazGraz, Austria
| | - Helmut Schwab
- Austrian Centre of Industrial BiotechnologyGraz, Austria
- Institute of Molecular Biotechnology, Graz University of TechnologyGraz, Austria
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Affiliation(s)
- Ashwini A. Ghogare
- Department
of Chemistry, Brooklyn College, 2900 Bedford Avenue, Brooklyn, New York 11210, United States
- Ph.D.
Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
| | - Alexander Greer
- Department
of Chemistry, Brooklyn College, 2900 Bedford Avenue, Brooklyn, New York 11210, United States
- Ph.D.
Program in Chemistry, The Graduate Center of the City University of New York, 365 Fifth Avenue, New York, New York 10016, United States
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11
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Zielinski Goldberg M, Burke LA, Samokhvalov A. Selective Activation of C=C Bond in Sustainable Phenolic Compounds from Lignin via Photooxidation: Experiment and Density Functional Theory Calculations. Photochem Photobiol 2015; 91:1332-9. [PMID: 26268649 DOI: 10.1111/php.12509] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 08/04/2015] [Indexed: 11/29/2022]
Abstract
Lignocellulosic biomass can be converted to high-value phenolic compounds, such as food additives, antioxidants, fragrances and fine chemicals. We investigated photochemical and heterogeneous photocatalytic oxidation of two isomeric phenolic compounds from lignin, isoeugenol and eugenol, in several nonprotic solvents, for the first time by experiment and the density functional theory (DFT) calculations. Photooxidation was conducted under ambient conditions using air, near-UV light and commercial P25 TiO2 photocatalyst, and the products were determined by TLC, UV-Vis absorption spectroscopy, HPLC-UV and HPLC-MS. Photochemical and photocatalytic oxidation of isoeugenol proceeds via the mild oxidative "dimerization" to produce the lignan dehydrodiisoeugenol (DHDIE), while photooxidation of eugenol does not proceed. The DFT calculations suggest a radical stepwise mechanism for the oxidative "dimerization" of isoeugenol to DHDIE as was calculated for the first time.
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Affiliation(s)
| | - Luke A Burke
- Chemistry Department, Rutgers University, Camden, NJ
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12
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13
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Rodrigo CP, James WH, Zwier TS. Single-conformation ultraviolet and infrared spectra of jet-cooled monolignols: p-coumaryl alcohol, coniferyl alcohol, and sinapyl alcohol. J Am Chem Soc 2011; 133:2632-41. [PMID: 21294542 DOI: 10.1021/ja109218j] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Single-conformation spectroscopy of the three lignin monomers (hereafter "monolignols") p-coumaryl alcohol (pCoumA), coniferyl alcohol (ConA), and sinapyl alcohol (SinA) has been carried out on the isolated molecules cooled in a supersonic expansion. Laser-induced fluorescence excitation, dispersed fluorescence, resonant two-photon ionization, UV-UV hole-burning, and resonant ion-dip infrared spectroscopy were carried out as needed to obtain firm assignments for the observed conformers of the three molecules. In each case, two conformers were observed, differing in the relative orientations of the vinyl and OH substituents para to one another on the phenyl ring. In pCoumA, the two conformers have S(0)-S(1) origins nearly identical in size, split from one another by only 7 cm(-1), in close analogy with previous results of Morgan et al. on p-vinylphenol ( Chem. Phys. 2008 , 347 , 340 ). ConA, with its methoxy group ortho to the OH group, also has two low-energy conformers forming a syn/anti pair, in this case with the OH group locked into an orientation in which it forms an intramolecular H-bond with the adjacent methoxy group. The electronic frequency shift between the two conformers is dramatically increased to 805 cm(-1), with the dominant conformer of ConA (with S(0)-S(1) origin at 32 640 cm(-1)) about 5 times the intensity of its minor counterpart (with S(0)-S(1) origin at 33 444 cm(-1)). The presence of an OH···OCH(3) intramolecular H-bond is established by the shift of the OH stretch fundamental of the OH group to 3599 cm(-1), as it is in o-methoxyphenol ( Fujimaki et al. J. Chem. Phys. 1999 , 110 , 4238 ). Analogous single-conformation UV and IR spectra of o-methoxy-p-vinylphenol show a close similarity to ConA and provide a basis for a firm assignment of the red-shifted (blue-shifted) conformer of both molecules to the syn (anti) conformer. The two observed conformers of SinA, with its two methoxy group straddling the OH group, have S(0)-S(1) origins split by 239 cm(-1) (33 055 and 33 294 cm(-1)), a value between those in pCoumA and ConA. A combination of experimental data and calculations on the three monolignols and simpler derivatives is used to establish that the conformational preferences of the monolignols reflect the preferences of each of the ring substituents separately, enhanced by the presence of the intramolecular OH···OCH(3) H-bond. Taken as a whole, the presence of multiple flexible substituents locks in certain preferred orientations of the groups relative to one another, even in the apparently flexible allyl alcohol side chain (-CH═CH-CH(2)OH), where the OH group orients itself so that the hydrogen is pointed back over the vinyl π cloud in order to minimize interactions between the oxygen lone pairs and the π electrons.
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Affiliation(s)
- Chirantha P Rodrigo
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA
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