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The efficient catalytic oxidation of 2,3,6-trimethylphenol with air over composite catalyst to synthesize Vitamin E intermediate. RESEARCH ON CHEMICAL INTERMEDIATES 2021. [DOI: 10.1007/s11164-021-04500-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Molecular iodine/DMSO mediated oxidation of internal alkynes and primary alcohols using a one-pot, two step approach towards 2,4,5-trisubstituted imidazoles: Substrate scope and mechanistic studies. Tetrahedron 2020. [DOI: 10.1016/j.tet.2020.131028] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Ancheeva E, Mándi A, Király SB, Kurtán T, Hartmann R, Akone SH, Weber H, Daletos G, Proksch P. Chaetolines A and B, Pyrano[3,2- f]isoquinoline Alkaloids from Cultivation of Chaetomium sp. in the Presence of Autoclaved Pseudomonas aeruginosa. JOURNAL OF NATURAL PRODUCTS 2018; 81:2392-2398. [PMID: 30343566 DOI: 10.1021/acs.jnatprod.8b00373] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The first members of a new alkaloid class, chaetolines A (1) and B (2), which feature a pyrano[3,2- f]isoquinoline core structure, were obtained from a crude extract of the fungal endophyte Chaetomium sp. after cultivation in the presence of autoclaved Pseudomonas aeruginosa. The structures of the new compounds, including the absolute configuration of the major stereoisomer, were determined through detailed analysis of HRESIMS, 1D/2D NMR, and calculation of ECD data. The possible biosynthetic origin of the unprecedented scaffold of 1 and 2 is proposed. The current study provides further evidence for mixed fermentation as a powerful tool to induce the accumulation of cryptic fungal natural products even in the absence of viable bacterial cells.
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Affiliation(s)
- Elena Ancheeva
- Institute of Pharmaceutical Biology and Biotechnology , Heinrich Heine University , Universitätsstrasse 1 , 40225 Düsseldorf , Germany
| | - Attila Mándi
- Department of Organic Chemistry , University of Debrecen , PO Box 400, 4002 Debrecen , Hungary
| | - Sándor B Király
- Department of Organic Chemistry , University of Debrecen , PO Box 400, 4002 Debrecen , Hungary
| | - Tibor Kurtán
- Department of Organic Chemistry , University of Debrecen , PO Box 400, 4002 Debrecen , Hungary
| | - Rudolf Hartmann
- Institute of Complex Systems: Strukturbiochemie (ICS-6) , Forschungszentrum Jülich , Wilhelm-Johnen-Strasse , 52428 Jülich , Germany
| | - Sergi H Akone
- Institute of Pharmaceutical Biology and Biotechnology , Heinrich Heine University , Universitätsstrasse 1 , 40225 Düsseldorf , Germany
- Faculty of Science, Department of Chemistry , University of Douala , PO Box 24157, Douala , Cameroon
| | - Horst Weber
- Institute of Pharmaceutical and Medicinal Chemistry , Heinrich Heine University , Universitätsstrasse 1 , 40225 Düsseldorf , Germany
| | - Georgios Daletos
- Institute of Pharmaceutical Biology and Biotechnology , Heinrich Heine University , Universitätsstrasse 1 , 40225 Düsseldorf , Germany
| | - Peter Proksch
- Institute of Pharmaceutical Biology and Biotechnology , Heinrich Heine University , Universitätsstrasse 1 , 40225 Düsseldorf , Germany
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Belattar S, Debbache N, Seraghni N, Sehili T. Transformation of Phenolic Compounds by Fe(III) in the Aqueous Solution in Dark and Under Irradiation. INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING 2015. [DOI: 10.1515/ijcre-2015-0053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The degradation of phenolic compounds (PC) by Fe(III) aquacomplexes was investigated in homogeneous phase at neutral pH in dark and using monochromatic irradiation lamp (365 nm). The process of degradation depends essentially on the concentration of monomeric species, which is the most reactive species in terms of HO• radicals formation. A dark study of a system containing a mixture of phenolic compounds (3,5-dimethylphenol, 2,6-dimethylphenol, m-methylphenol, phenol) and Fe(III) was performed before starting the photochemical study. In this step only the 2,6-dimethylphenol give a thermal reaction with iron in homogenous solution. Under monochromatic excitation (365 nm), the photodegradation of PC induced by Fe(III) aquacomplexes showed that this process followed pseudo first-order kinetic. We investigate also the effect of initial concentrations of Fe(OH)2+, Fe(III) and the substrate. Tertiobutanol, used as scavenger of (HO•), confirmed that this radical was the main pathway of PC degradation. However the degradation of the 2,6-dimethylphenol in the presence of tertiobutanol, was not slowed completely which confirm that the degradation was a combination of thermal and photochemical reactions.
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Affiliation(s)
- S. Belattar
- Laboratory of science and technology of the environment, University of Mentouri, 25000 Constantine, Algeria
| | - N. Debbache
- Laboratory of science and technology of the environment, University of Mentouri, 25000 Constantine, Algeria
| | - N. Seraghni
- Laboratory of science and technology of the environment, University of Mentouri, 25000 Constantine, Algeria
| | - T. Sehili
- Laboratory of science and technology of the environment, University of Mentouri, 25000 Constantine, Algeria
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Wang Z, Liu J. New insight into photochemical oxidation of Fe(II): The roles of Fe(III) and reactive oxygen species. Catal Today 2014. [DOI: 10.1016/j.cattod.2013.09.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Simon A, Ballai C, Lente G, Fábián I. Structure–reactivity relationships and substituent effect additivity in the aqueous oxidation of chlorophenols by cerium(iv). NEW J CHEM 2011. [DOI: 10.1039/c0nj00529k] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Mazellier P, Méité L, De Laat J. Photodegradation of the steroid hormones 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2) in dilute aqueous solution. CHEMOSPHERE 2008; 73:1216-1223. [PMID: 18762316 DOI: 10.1016/j.chemosphere.2008.07.046] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 07/16/2008] [Accepted: 07/20/2008] [Indexed: 05/26/2023]
Abstract
The photochemical transformation of natural estrogenic steroid 17beta-estradiol (E2) and the synthetic oral contraceptive 17alpha-ethinylestradiol (EE2) has been studied in dilute non buffered aqueous solution (pH 5.5-6.0) upon monochromatic (254 nm) and polychromatic (lambda>290 nm) irradiation. Upon irradiation at 254 nm, the quantum yields of E2 and EE2 photolysis were similar and evaluated to be 0.067+/-0.007 and 0.062+/-0.007, respectively. Upon polychromatic excitation, and by using phenol as chemical actinometer, the photolysis efficiencies have been determined to be 0.07+/-0.01 and 0.08+/-0.01 for E2 and EE2, respectively. For both estrogens, photodegradation by-products were identified with GC/MS and LC/MS. In a first step, a model compound--5,6,7,8-tetrahydro-2-naphthol (THN)--, which represents the photoactive phenolic group, was used to obtain basic photoproduct structural informations. Numerous primary and secondary products were observed, corresponding to hydroxylated phenolic- or quinone-type compounds.
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Affiliation(s)
- Patrick Mazellier
- Laboratoire de Chimie de l'Eau et de l'Environnement, UMR CNRS 6008, Université de Poitiers ESIP, 40, Avenue du Recteur Pineau, 86022 Poitiers Cedex, France.
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Wong-Wah-Chung P, Mailhot G, Aguer JP, Bolte M. Fate of a stilbene-type fluorescent whitening agent (DSBP) in the presence of Fe(III) aquacomplexes: from the redox process to the photodegradation. CHEMOSPHERE 2006; 65:2185-92. [PMID: 16860369 DOI: 10.1016/j.chemosphere.2006.05.074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2006] [Revised: 05/30/2006] [Accepted: 05/31/2006] [Indexed: 05/11/2023]
Abstract
The behaviour of 4,4'-bis(2-sulfostyryl)biphenyl (DSBP), a fluorescent whitening agent, was investigated in the presence of Fe(III) aquacomplexes at room temperature. In the dark, a two-step reaction was observed when adding Fe(III) to a solution of DSBP: an initial fast redox reaction between DSBP and the monomeric species Fe(OH)(2+) and a slower reaction leading to the coagulation of oxidised DSBP and iron. This phenomenon is due to the formation of a complex or an ion-pair between Fe(II) and/or Fe(III) with oxidised DSBP and it probably occurs by charge neutralisation in our experimental conditions. The precipitation of DSBP depends on the initial concentration in Fe(OH)(2+) and is achieved for a ratio [Fe(OH) (2+)]/[DSBP] of 5 approximately. Under irradiation at 365 nm, a complicated behaviour was observed: a complexation of iron by oxidised DSBP favoured by irradiation and a degradation of DSBP induced by an intramolecular electron transfer in the complex or by a photoredox of Fe(OH)(2+) species generating .OH radicals in the supernatant. The complete degradation of DSBP is reached four times faster in the presence of Fe(III) with respect to the direct photolysis of DSBP alone. Moreover, the total mineralization of DSBP obtained in less than 120 h upon irradiation at 365 nm is only observed in the presence of the ferric ions, enlightening the efficiency of the method involving Fe(III) and UV irradiation.
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Affiliation(s)
- Pascal Wong-Wah-Chung
- Laboratoire de Photochimie Moléculaire et Macromoléculaire, CNRS, Université Blaise Pascal, UMR 6505, 63177 Aubière Cedex, France
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