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1

Kopecký, Jaroslav, David Šaman, and Ladislav Novotný. "Methylation of substituted 1,4-benzoquinones." Collection of Czechoslovak Chemical Communications 52, no. 1 (1987): 228–32. http://dx.doi.org/10.1135/cccc19870228.

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Methylation of 1,4-benzoquinones I and Ia with diazomethane afforded methyl 15-(6-methoxy-3-methyl-1,4-benzoquinon-2-yl)pentadecanoate (IIa) and methyl 15-(3-methoxy-2,5-dioxobicyclo[4.1.0]hept-3-en-1-yl)pentadecanoate (IIIa), methylation of 1,4-benzoquinone IVa led to methyl 15-(5,6-dimethoxy-3-methyl-1,4-benzoquinon-2-yl)pentadecanoate (Va) and methyl 15-(3,4-dimethoxy-6-methyl-2,5-dioxobicyclo[4.1.0]hept-3-en-1-yl)pentadecanoate (VIa). Structure of the products was established by spectral methods.
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2

Duarte, Sónia, Ana Magro, Joanna Tomás, Carolina Hilário, Ricardo Boavida Ferreira, and Maria Otília Carvalho. "Antifungal Activity of Benzoquinones Produced by Tribolium castaneum in Maize-Associated Fungi." Insects 13, no. 10 (2022): 868. http://dx.doi.org/10.3390/insects13100868.

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Tribolium castaneum (Herbst) adults produce 1,4-benzoquinone (BQ), methyl-1,4-benzoquinone (MBQ), and ethyl-1,4-benzoquinone (EBQ). These components are chemical defenses used as repellents and irritants, and BQ has a negative impact on the growth of some fungal species. In this work, the inhibitory and/or lethal effects of these benzoquinones on the development of six fungi identified in maize, namely Aspergillus flavus, A. fumigatus, A. niger, Fusarium sp., Penicillium sp., and Trichoderma sp., were evaluated. Ten-day-long disk diffusion trials were performed using benzoquinones. The experim
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3

Katritzky, Alan R., Herman H. Odens, Michael V. Voronkov, Charles J. Rostek, and Otto W. Maender. "Rubber Chemicals Derived from Conjugate Addition. I. Syntheses of Novel 2-Thio-5-Amino Substituted Benzoquinones." Rubber Chemistry and Technology 74, no. 5 (2001): 915–25. http://dx.doi.org/10.5254/1.3547661.

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Abstract Alkylthio-substituted benzoquinones were prepared from benzoquinone and mercaptans in 50–94% yields via NaIO4 oxidation of the intermediate hydroquinones. Subsequent addition of primary and secondary amines, in the presence of air as an oxidizing agent, gave a range of 2-thio-5-amino-substituted benzoquinones. No oxidation at sulfur was detected under the described conditions.
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4

Renger, Gernot, Angela Kayed, and Walter Oettmeier. "Interaction of Halogenated 1,4-Benzoquinones with System II of Photosynthesis." Zeitschrift für Naturforschung C 42, no. 6 (1987): 698–703. http://dx.doi.org/10.1515/znc-1987-0609.

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The interaction of halogenated p-benzoquinones with PS II has been analyzed by measurements of fluorescence induction curves and the average oxygen yield per flash in isolated class II chloroplasts. It was found: 1)The normalized area over the fluorescence induction curve in the presence of DCMU. A/Fmax, markedly increases if halogenated p-benzoquinones are added before DCMU. The effect is eliminated by DCMU addition prior to that of the quinones. 2)The extent of A/Fmax increases with increasing dark time between the additions of 2,3.5-tri- bromo-6-methyl-1,4-benzoquinone (TBTO) and DCMU. resp
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5

KACMAZ, Aysecik. "SYNTHESIS OF MONO(THIO)-, BIS(THIO)- AND MONO(AMINO)-SUBSTITUTED 1,4-BENZOQUINONES." Revue Roumaine de Chimie 69, no. 10-12 (2024): 635–42. https://doi.org/10.33224/rrch.2024.69.10-12.14.

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Twelve thio- and amino- benzoquinones (3a-d, 5a, 5b, 7d, 8d, 10e, 11e, 13e and 13f) were synthesized from benzoquinones (p-benzoquinone 1, p-toluquinone 6 and 2-tert-butyl-1,4-benzoquinone 12) with thiols or primary amines. Among them, compounds 3a-3d and 5a,b have mono(thio)- and bis(thio)- substituted-benzoquinone structures, respectively. The compounds 2-(3,4-dimethylphenylthio)-6- (tetradecylthio)cyclohexa-2,5-diene-1,4-dione (5a) and 2-(3,4- dimethoxyphenylthio)-6-(tetradecylthio)cyclohexa-2,5-diene-1,4-dione, (5b) include two different thio- groups in each of them. Compounds 7d and 8d ha
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6

Oettmeier, Walter, and Silvana Preuße. "Herbicide and Quinone Binding to Chromatophores and Reaction Centers from Rhodobacter sphaeroides." Zeitschrift für Naturforschung C 42, no. 6 (1987): 690–92. http://dx.doi.org/10.1515/znc-1987-0607.

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Besides s-triazine and triazinone herbicides the chromone stigmatellin and tetrahalogen-substituted 1.4-benzoquinones are inhibitors of photosynthetic electron flow from reduced cytochrome c to ubiquinone-6 in isolated bacterial reaction centers. With isolated bacterial chromatophores binding experiments with radiolabeled herbicides can be performed in a similar way as with thylakoids from higher plants. Tetrahalogen-substituted 1.4-benzoquinones in a Michael type reaction can add onto nucleophilic groups in proteins. In bacterial reaction centers, a [14C]tetra- bromo-1.4-benzoquinone (bromani
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7

Netzly, David H., James L. Riopel, Gebisa Ejeta, and Larry G. Butler. "Germination Stimulants of Witchweed (Striga asiatica) from Hydrophobic Root Exudate of Sorghum (Sorghum bicolor)." Weed Science 36, no. 4 (1988): 441–46. http://dx.doi.org/10.1017/s0043174500075172.

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Hydrophobic exudate from roots of sorghum [Sorghum bicolor(L.) Moench. #3SORVU ‘IS 8768’] contain fourp-benzoquinones which in the dihydroquinone form are active as germination stimulants of witchweed [Striga asiatica(L.) Kuntz. # STRLU]. The three minorp-benzoquinones were partially characterized and found to be structurally similar to sorgoleone, the majorp-benzoquinone of this exudate. Herbicidal activity of the hydrophobic exudate was due to concentration- and pH-dependent inhibition of root elongation in some but not all weeds tested. Witchweed has apparently adapted these “defense” compo
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8

Kopecký, Jaroslav, David Šaman, and Ladislav Novotný. "Methoxylation of substituted 1,4-benzoquinones." Collection of Czechoslovak Chemical Communications 52, no. 1 (1987): 223–27. http://dx.doi.org/10.1135/cccc19870223.

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Methoxylation of 1,4-benzoquinones I and Ia with boron trifluoride-methanol complex afforded methyl 15-(5,6-dimethoxy-1,4-benzoquinon-2-yl)pentadecanoate (IIa) and methyl 15-(2-hydroxy-3,5-dimethoxyphenyl)pentadecanoate (IIIa). Structure of the products was established by spectroscopic methods.
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9

Fernández-Aparicio, Mónica, Marco Masi, Alessio Cimmino, and Antonio Evidente. "Effects of Benzoquinones on Radicles of Orobanche and Phelipanche Species." Plants 10, no. 4 (2021): 746. http://dx.doi.org/10.3390/plants10040746.

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The holoparasitic broomrape weeds (Orobanche and Phelipanche species) cause severe yield losses throughout North Africa, the Middle East, and Southern and Eastern Europe. These parasitic weeds form an haustorium at the tip of their radicles to infect the crop upon detection of the host-derived haustorium-inducing factors. Until now, the haustorial induction in the broomrapes remains less studied than in other parasitic plant species. Known haustorium-inducing factors active in hemiparasites, such as Striga and Triphysaria species, were reported to be inefficient for the induction of haustoria
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10

Reddy V, Sivarama Krishna, and V. V. Satyanarayana Peruri. "Synthesis of Substituted 1,4-Benzoxazine Derivatives through Diels-Alder Reaction." Caribbean Journal of Science and Technology 07, no. 01 (2019): 88–95. http://dx.doi.org/10.55434/cbi.2019.7111.

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An efficient synthetic protocol is presented for accessing 1,4-benzoxazine derivatives from 2-amino phenol derivatives via o-benzoquinones. The key step involves the Diels-Alder reaction between highly reactive o-quinone monoiminewith butyl vinyl ether/thioether to generate various benzoquinone derivatives.
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11

Warsen, Meredith G., Soren Zimmer, Katherine Phan, and Lisa M. Landino. "Photochemical Redox Reactions of 2,6-Dichlorophenolindophenol and Its Use to Detect Photoreduced Quinones." Photochem 5, no. 3 (2025): 19. https://doi.org/10.3390/photochem5030019.

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Photosynthesis in plants and the electron transport chain in mitochondria are examples of life-sustaining electron transfer processes. The benzoquinones plastoquinone and ubiquinone are key components of these pathways that cycle through their oxidized and reduced forms. Previously, we reported direct photoreduction of biologically relevant quinones mediated by photosensitizers, red light and electron donors. Herein we examined direct photoreduction of the quinone imine 2,6-dichlorophenolindophenol (DCPIP) using red light, methylene blue as the photosensitizer and ethylenediaminetetraacetic ac
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12

Bozic, Tatjana, Dusan Sladic, Mario Zlatovic, Irena Novakovic, Snezana Trifunovic, and Miroslav Gasic. "Regioselectivity of conjugate additions to monoalkyl-1,4-benzoquinones." Journal of the Serbian Chemical Society 67, no. 8-9 (2002): 547–51. http://dx.doi.org/10.2298/jsc0209547b.

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The regioselectivity of the reaction of conjugate addition of thiols amines, methanol and hydrogen chloride with the monoalkyl-1,4-benzoquinones avarone and 2-tert-butyl- 1,4-benzoquinone was investigated. It was shown that the regioselectivity of the reaction is influenced by the electrophilicity of position 5 in unprotonated 2-alkylquinones, the increased electrophilicity of position 6 in acidic medium, and by the acidity of the intermediate hydroquinones.
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13

Boone, Harold W., Justin Bryce, Tamara Lindgren, Anne Buyle Padias, and H. K. Hall. "Stereoregular Poly(benzoquinone imines) from Methyl-Substituted Benzoquinones." Macromolecules 30, no. 9 (1997): 2797–99. http://dx.doi.org/10.1021/ma961236j.

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14

Davyt-Colo, Belén, Juan R. Girotti, Andrés González, and Nicolás Pedrini. "Secretion and Detection of Defensive Compounds by the Red Flour Beetle Tribolium castaneum Interacting with the Insect Pathogenic Fungus Beauveria bassiana." Pathogens 11, no. 5 (2022): 487. http://dx.doi.org/10.3390/pathogens11050487.

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Entomopathogenic fungi such as Beauveria bassiana are extensively used for the control of insect pests worldwide. They infect mostly by adhesion to the insect surface and penetration through the cuticle. However, some insects, such as the red flour beetle Tribolium castaneum (Herbst), have evolved resistance by embedding their cuticle with antifungal compounds. Thus, they avoid fungal germination on the cuticle, which result in low susceptibility to entomopathogenic fungi. In adult T. castaneum, these antifungals are the well-known defensive compounds methyl-1,4- and ethyl-1,4-benzoquinone. In
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15

König., Wilfried A., Holger Faasch, Holger Heitsch, Cornelia Colberg, and Björn M. Hausen. "Synthese von seitenkettenmodifizierten Analogen des Allergens Primin / Synthesis of Side-Chain-Modified Analogues of the Allergen Primin." Zeitschrift für Naturforschung B 48, no. 3 (1993): 387–93. http://dx.doi.org/10.1515/znb-1993-0318.

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Benzoquinones such as primin (2-methoxy-6-pentyl-1,4-benzoquinone) from Primula obconica HANCE (Primulaceae) are known to be strong sensitizers and thus the source of severe allergic contact dermatitis (cell-mediated type of allergy). In order to determine the relationship between sensitizing capacity and chemical structure the synthesis of 19 side-chain-modified analogues of primin was carried out. With each of these primin derivatives 10 guinea pigs were sensitized using a modified FCA-method (FCA = Freund’s complete adjuvant). Elicitation was done open epicutaneously with 0.001 molar concen
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16

Krol, Marianna, and Norman P. A. Huner. "Growth and development at cold-hardening temperatures. Pigment and benzoquinone accumulation in winter rye." Canadian Journal of Botany 63, no. 4 (1985): 716–21. http://dx.doi.org/10.1139/b85-090.

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Accumulation of chlorophyll, the carotenoids (β-carotene, lutein, violaxanthin, and neoxanthin), and the benzoquinones (plastoquinone A and α-tocopherol) were monitored in 'Puma' rye as a function of leaf ontogeny at warm and cold-hardening temperatures. Although the kinetics of accumulation differed among the leaves of warm-grown plants, the initial and maximum levels of the pigments and benzoquinones expressed on a leaf area basis did not differ significantly among the first four leaves of the main culm. In contrast, the third and fourth leaf of cold-grown plants, which developed completely
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17

Silakari, Pragati, Priyanka, and Poonam Piplani. "p-Benzoquinone as a Privileged Scaffold of Pharmacological Significance: A Review." Mini-Reviews in Medicinal Chemistry 20, no. 16 (2020): 1586–609. http://dx.doi.org/10.2174/1389557520666200429101451.

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Quinones are a huge class of compounds with affluent and captivating chemistry. p-Benzoquinone (p-BNZ) or 1,4-Benzoquinone is the key structural motif of numerous biologically active synthetic and natural compounds. This draws interest in its biological exploration to assess prospective therapeutic implications. It possesses immense therapeutic potential depending on different substitutions. This moiety has a marvelous potential to regulate a varied range of different cellular pathways which can be investigated for various selective activities. p-Benzoquinones have been a requisite core for th
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18

Gomaa, Mohsen A. M. "Synthesis and Spectral Analysis of 3,4,5-trichloro-6-(dibenzo[d,f][1,3]diazepin-5-yl)-[1,2]-benzoquinones." E-Journal of Chemistry 8, s1 (2011): S91—S96. http://dx.doi.org/10.1155/2011/726420.

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Reaction ofN1,N2-di-(4-methoxyphenyl)- orN1,N2-di-(4-hydroxyphenyl) -amidines (1a-d) with 3,4,5,6-tetrachloro-1,2-benzoquinone (2) in ethyl acetate at room temperature led to formation of new 3,4,5-trichloro-6-(2-hydroxy-6-methyldibenzo[d,f][1,3]diazepin-5-yl[1,2]-benzoquinones (3a-d) in addition toN-aryl-N'-(6,7,8,9-tetrachloro-4-hydroxydibenzo-[1,4]dioxin-2-yl)acetamidines (4a,b). The rational of formation of products3a-dand4a,bwas discussed and structures were confirmed on the basis of elemental analysis and spectral data.
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19

KAÇMAZ, Ayşecik. "Some amino- and thio- substituted 1,4-quinones: synthesis and characterization." Revue Roumaine de Chimie 69, no. 7-8 (2024): 391–98. http://dx.doi.org/10.33224/rrch.2024.69.7-8.06.

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Some bromine/chlorine substituted aminonaphthoquinones (3a-c, 7a) and NH, NH- substituted 1,4-benzoquinones (9a, 9b and 9d) were synthesized by the reaction of quinones (2,3-dibromo/chloro-1,4-naphthoquinone (1, 6) or 2,6-dichloro-1,4-benzoquinone (8)) with amines (2a-d). Reaction of aminonaphthoquinones (3a, 3b and 3c) with sodium 2-propanethiolate (4) yielded naphthoquinones with both NH- and S- substituents (5a, 5b and 5c). All synthesized compounds were characterized, providing 1H-NMR, 13C-NMR, MS(ESI), IR, UV/Vis and elemental analysis.
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20

Ivan, Beatrice Cristina, Mino Rodolfo Caira, and Florea Dumitrascu. "Nenitzescu Indole Synthesis: 1929-2019 Unexpected Formation of a Pyrrole-Azepine Hybrid in the Nenitzescu Indole Synthesis: A Reinvestigation." Revista de Chimie 71, no. 5 (2020): 51–57. http://dx.doi.org/10.37358/rc.20.5.8112.

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The condensation of 1,4-benzoquinones with enamines reported ninety years ago is a name reaction known as the Nenitzescu indole synthesis which has proved to be a very useful method for obtaining both 5-hydroxyindoles and nonindole derivatives. An unexpected compound containing two condensed azepine rings was isolated in 1988 from the reaction between 1,4-benzoquinone and ethyl 3-aminocinnamate performed in 1-butanol. The reinvestigation of the proposed bisazepine structure by X-ray analysis revealed instead a pyrrole-azepine hybrid having the two heterocycles rings connected by a double bond.
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21

Amaro-Luis, Juan Manuel, Sonia Koteich-Khatib, Freddy Carrillo-Rodríguez, and Alí Bahsas. "Myrsicorianol, A New Prenylated Benzoic Acid Derivative from Myrsine Coriacea." Natural Product Communications 3, no. 3 (2008): 1934578X0800300. http://dx.doi.org/10.1177/1934578x0800300304.

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A new prenylated benzoic acid derivative, named myrsicorianol (1), was isolated from the fruits of Myrsine coriacea and its structure was determined by spectral analysis, including 1D- and 2D-NMR experiments. Myrsinoic acid A and a mixture of the p-benzoquinones, embelin, rapanone and 2,5-dihydroxy-3-pentadecyl-1,4-benzoquinone (homorapanone) were also obtained from the fruits, whilst the bark afforded myrsinoic acid A, myrsinoic acid B, 3-(3′,7′-dimethyl-2′,6′-octadienyl)-4-hydroxybenzoic acid and 3-(3′,7′-dimethyl-2′,6′-octadienyl)-4-methoxybenzoic acid.
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22

Carlini, Rina, Kerianne Higgs, Nicholas Taylor, and Russell Rodrigo. "Diels–Alder adducts of ortho-benzoquinones: rearrangements and further transformations." Canadian Journal of Chemistry 75, no. 6 (1997): 805–16. http://dx.doi.org/10.1139/v97-097.

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ortho-Benzoquinones substituted with an electron-withdrawing group (EWG = CO2Me, COSMe, COCH3, CHO) at C-3 or C-4 react as dienophiles at the C3—C4 double bond in Diels–Alder reactions with several dienes, with predictable regiochemistry. The adducts undergo migration of the "angular" EWG substituent with concomitant aromatization to produce substituted catechols. The bicyclic products can be oxidized in situ and annelated by a further Diels–Alder reaction to yield 9,10-phenanthraquinone systems. When (2E)-2,4-pentadienol is employed as the diene in the second cycloaddition, reaction of the al
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23

Lungu, Claudiu N., Violeta Mangalagiu, Ionel I. Mangalagiu, and Mihaela C. Mehedinti. "Benzoquinoline Chemical Space: A Helpful Approach in Antibacterial and Anticancer Drug Design." Molecules 28, no. 3 (2023): 1069. http://dx.doi.org/10.3390/molecules28031069.

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Benzoquinolines are used in many drug design projects as starting molecules subject to derivatization. This computational study aims to characterize e benzoquinone drug space to ease future drug design processes based on these molecules. The drug space is composed of all benzoquinones, which are active on topoisomerase II and ATP synthase. Topological, chemical, and bioactivity spaces are explored using computational methodologies based on virtual screening and scaffold hopping and molecular docking, respectively. Topological space is a geometrical space in which the elements composing it can
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24

Yokoji, Takato, Hiroshi Matsubara, and Masaharu Satoh. "Rechargeable organic lithium-ion batteries using electron-deficient benzoquinones as positive-electrode materials with high discharge voltages." J. Mater. Chem. A 2, no. 45 (2014): 19347–54. http://dx.doi.org/10.1039/c4ta02812k.

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Electron-deficient benzoquinones bearing perfluoroalkyl groups were examined as cathode active materials in rechargeable batteries. The cells afforded higher discharge voltages than those using electron-rich benzoquinones.
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25

Bock, Hans, Sabine Nick, Wolfgang Seitz, Christian Näther, and Jan W. Bats. "Strukturen ladungsgestörter oder räumlich überfüllter Moleküle, 80 [1 - 3] Strukturänderungen von p-Benzochinon durch Donator- und Akzeptor-Substituenten." Zeitschrift für Naturforschung B 51, no. 2 (1996): 153–71. http://dx.doi.org/10.1515/znb-1996-0201.

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Abstract The structures of seven di- or tetrasubstituted p-benzoquinone derivatives O=C(XC=CH )2C=O and O=C(XC=CX)2C=O with substituents X = -OCH3, -N(CH2)5, - N(CH2CH2)2O, -Cl, -CN and -⊕N(HC=CH)2C-N(CH3)2 are presented and discussed in comparison with published ones substituted by X = -Si(CH3)3, -C6H5, -N(CH3)2, -⊕N(HC=CH)2CN(CH3)2, -O⊖ , and - NO2. Based on the introduction, in which halfwave-reduction potentials, geometry-optimized quantum-chemical calculations on substituent perturbation and known structural data of p-benzoquinone derivatives are used to characterize their molecular groun
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26

Farooq, Umer, Yanjun Pan, Dejene Disasa, and Jianhua Qi. "Novel Anti-Aging Benzoquinone Derivatives from Onosma bracteatum Wall." Molecules 24, no. 7 (2019): 1428. http://dx.doi.org/10.3390/molecules24071428.

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The aim of this study was to investigate anti-aging molecules from Onosma bracteatum Wall, a traditional medicinal plant used in the Unani and Ayurvedic systems of medicine. During bioassay-guided isolation, two known benzoquinones, allomicrophyllone (1) and ehretiquinone (2) along with three novel benzoquinones designated as ehretiquinones B–D (3−5) were isolated from O. bracteatum. Their structures were characterized by spectroscopic analysis through 1D and 2D NMR, by MS spectroscopic analysis and comparing with those reported in the literatures. The anti-aging potential of the isolated benz
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27

Rojas-Aguilar, Aarón, Honorio Flores-Lara, Melchor Martinez-Herrera, and Francisco Ginez-Carbajal. "Thermochemistry of benzoquinones." Journal of Chemical Thermodynamics 36, no. 6 (2004): 453–63. http://dx.doi.org/10.1016/j.jct.2004.03.002.

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28

Shurygina, M. P., N. O. Druzhkov, M. V. Arsen’ev, et al. "Alkoxylation of 3,6-di-tert-butyl-1,2-benzoquinone. New bis-1,2-benzoquinones." Russian Journal of Organic Chemistry 47, no. 4 (2011): 486–95. http://dx.doi.org/10.1134/s1070428011040038.

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29

Koike, Hiroyuki, Yasuhiro Kashino, and Kazuhiko Satoh. "Interactions of Halogenated Benzoquinones with the Non-Heme Iron (Q400) in Photosystem II." Zeitschrift für Naturforschung C 48, no. 3-4 (1993): 168–73. http://dx.doi.org/10.1515/znc-1993-3-410.

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Abstract Interactions of halogenated benzoquinones with the acceptor side of Photosystem (PS) II were studied by measuring fluorescence induction curves and flash-induced absorbance changes in PS II particles isolated from Synechococcus vulcanus. Following results were obtained: 1) Addition of some halogenated benzoquinones prior to 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) in the dark increased the area above the fluorescence induction curve (work integral) by a factor of two. 2) Based on the ability to increase the fluorescence work integral, halogenated benzoquinones could be divided i
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30

Benites, Julio, Jaime A. Valderrama, Maryan Ramos, et al. "Half-Wave Potentials and In Vitro Cytotoxic Evaluation of 3-Acylated 2,5-Bis(phenylamino)-1,4-benzoquinones on Cancer Cells." Molecules 24, no. 9 (2019): 1780. http://dx.doi.org/10.3390/molecules24091780.

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A broad range of 3-acyl-2,5-bis(phenylamino)-1,4-benzoquinones were synthesized and their voltammetric values, as well as in vitro cancer cell cytotoxicities, were assessed. The members of this series were prepared from acylbenzoquinones and phenylamines, in moderate to good yields (47–74%), through a procedure involving a sequence of two in situ regioselective oxidative amination reactions. The cyclic voltammograms of the aminoquinones exhibit two one-electron reduction waves to the corresponding radical-anion and dianion, and two quasi-reversible oxidation peaks. The first and second half-wa
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den Besten, C., A. Brouwer, I. M. C. M. Rietjens, and P. J. van Bladeren. "Biotransfiormation and Toxicity of Halogenated Benzenes." Human & Experimental Toxicology 13, no. 12 (1994): 866–75. http://dx.doi.org/10.1177/096032719401301209.

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1 Multiple potentially harmful metabolites can be distinguished in the metabolic activation of halogenated benzenes: epoxides, phenols, benzoquinones and benzoquinone-derived glutathione conjugates. 2 The role of these (re-) active metabolites in the toxic effects induced by halogenated benzenes such as hepatotoxicity, nephrotoxicity, porphyria and thyroid toxicity is discussed. 3 Evidence is presented suggesting that the formation of reactive benzoquinone metabolites rather than the traditional epoxides is linked to halogenated benzene-induced hepatotoxicity. 4 A crucial role for the benzoqui
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Lund, Anne-Kristine, John Lemmich, Anne Adsersen, and Carl E. Olsen. "Benzoquinones from Embelia angustifolia." Phytochemistry 44, no. 4 (1997): 679–81. http://dx.doi.org/10.1016/s0031-9422(96)00606-1.

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Mathew, Abraham E., Robert K. Y. Zee-Cheng, and C. C. Cheng. "Amino-substituted p-benzoquinones." Journal of Medicinal Chemistry 29, no. 9 (1986): 1792–95. http://dx.doi.org/10.1021/jm00159a041.

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34

Nyquist, Richard A., Davin A. Luoma, and Curtis L. Putzig. "Infrared and raman study of 1,4-benzoquinone and substituted 1,4-benzoquinones in dilute solutions." Vibrational Spectroscopy 3, no. 3 (1992): 181–210. http://dx.doi.org/10.1016/0924-2031(92)87002-w.

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35

Lis, Ł. B., and T. Bakuła. "The influence of the feeding Flour Beetle Tribolium confusum-infested fodder on the selected indices of the health status of rats." Polish Journal of Veterinary Sciences 18, no. 3 (2015): 499–506. http://dx.doi.org/10.1515/pjvs-2015-0065.

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Abstract The present experiment was designed to demonstrate differences in the degree of fodder contamination with benzoquinones at various Tribolium confusum levels, the impact of infested feed on the beetle population and the impact of infested feed on the health status of rats. The feeding studies were done on female rats divided into 3 groups: a control group and two experimental groups. Experimental groups were fed with a fodder infested by 150 individuals of T. confusum per kg (group D1) and 300 individuals of T. confusum per kg (group D2). The insects were grown in the fodder for 5 mont
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36

Pokhodylo, Nazariy, Roman Martyak, Mykola Тupychak, Khrystyna Pitkovych, Vasyl Matiychuk, and Mykola Obushak. "The (1H-Tetrazol-1-yl)arenediazonium Salts as Convenient Reagents for Quinones Arylation: Synthesis of 1,3-Benzoxathiol-2-ones and Naphtho[2,1-d][1,3]oxathiol-2-ones Bearing (1H-Tetrazol-1-yl)phenyl Motif." Chemistry & Chemical Technology 17, no. 2 (2023): 304–14. http://dx.doi.org/10.23939/chcht17.02.304.

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A convenient two-step method for the synthesis of novel 1,3-benzoxathiol-2-ones and naphtho[2,1-d][1,3]oxathiol-2-ones bearing (1H-tetrazol-1-yl)phenyl motif was developed. As a key step of the synthesis, an arylation of quinones (1,4-benzoquinone, 1,4-naphtho-quinones) with the (1H-tetrazol-1-yl)arenediazonium salts was studied and efficient protocols were elaborated to obtain a variety of substituted ((1H-tetrazol-1-yl)phenyl) benzo/naphtho-1,4-quinones in good to excellent yields. An alternative synthesis of ((1H-tetrazol-1-yl)phenyl) naphtho-1,4-quinones via Diels-Alder reaction of tetrazo
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Danchovski, Yanislav, Hristo Rasheev, Radostina Stoyanova, and Alia Tadjer. "Molecular Engineering of Quinone-Based Nickel Complexes and Polymers for All-Organic Li-Ion Batteries." Molecules 27, no. 20 (2022): 6805. http://dx.doi.org/10.3390/molecules27206805.

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All-organic Li-ion batteries appear to be a sustainable and safer alternative to the currently-used Li-ion batteries but their application is still limited due to the lack of organic compounds with high redox potentials toward Li+/Li0. Herein, we report a computational design of nickel complexes and coordination polymers that have redox potentials spanning the full voltage range: from the highest, 4.7 V, to the lowest, 0.4 V. The complexes and polymers are modeled by binding low- and high-oxidized Ni ions (i.e., Ni(II) and Ni(IV)) to redox-active para-benzoquinone molecules substituted with ca
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Wróbel-Biedrawa, Dagmara, Monika Kubacka, Magdalena Kotańska, Marek Bednarski, Karolina Grabowska, and Irma Podolak. "Comparative Evaluation of Vasorelaxant and Antiplatelet Activity of Two Plant-Derived Benzoquinones: Rapanone and Embelin." Molecules 30, no. 4 (2025): 845. https://doi.org/10.3390/molecules30040845.

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Vasorelaxant and antiplatelet agents play an important role in preventing and combating endothelial dysfunction, atherosclerosis and a plethora of associated cardiovascular diseases (CVDs). CVDs are the leading cause of death worldwide and nowadays occur not only in developed but also in developing societies. They include, among others, coronary heart disease, cerebrovascular disease and peripheral artery disease. Due to their high prevalence, it is important to seek efficient preventive measures, such as lifestyle changes and the implementation of appropriate herbal dietary supplementation an
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Carcamo-Noriega, Edson Norberto, Shyam Sathyamoorthi, Shibdas Banerjee, et al. "1,4-Benzoquinone antimicrobial agents againstStaphylococcus aureusandMycobacterium tuberculosisderived from scorpion venom." Proceedings of the National Academy of Sciences 116, no. 26 (2019): 12642–47. http://dx.doi.org/10.1073/pnas.1812334116.

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Two 1,4-benzoquinone derivatives, found in the venom of the scorpionDiplocentrus melicifollowing exposure to air, have been isolated, characterized, synthesized, and assessed for antimicrobial activities. Initially a white, viscous liquid, the extracted venom colors within minutes under ambient conditions. From this colored mixture, two compounds, one red, the other blue, were isolated and purified using chromatography. After a variety of NMR and mass spectrometry experiments, the red compound was determined to be 3,5- dimethoxy-2-(methylthio)cyclohexa-2,5-diene-1,4-dione, and the blue compoun
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40

Görner, Helmut, and Clemens von Sonntag. "Photoprocesses of Chloro-Substitutedp-Benzoquinones." Journal of Physical Chemistry A 112, no. 41 (2008): 10257–63. http://dx.doi.org/10.1021/jp805046p.

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41

Wriede, Ulrich, Mario Fernandez, Kevin F. West, Dale Harcour, and Harold W. Moore. "Synthesis of halodimethoxy-1,2-benzoquinones." Journal of Organic Chemistry 52, no. 20 (1987): 4485–89. http://dx.doi.org/10.1021/jo00229a011.

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INOUE, Yoshinori, Katsuya OKUMURA, and Hidehiko KITAJIMA. "Syntheses of Arylated p-Benzoquinones." NIPPON KAGAKU KAISHI, no. 10 (1994): 913–20. http://dx.doi.org/10.1246/nikkashi.1994.913.

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Kukharev, B. F., V. K. Stankevich, and G. R. Klimenko. "2,5-Bis(vinyloxyalkylamino)-1,4-benzoquinones." Russian Journal of Organic Chemistry 47, no. 8 (2011): 1259–60. http://dx.doi.org/10.1134/s1070428011080264.

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Nanasawa, Masato, Hiroshi Takahashi, and Tetsuo Kuwabara. "FACILE SYNTHESES OFP-(DICYANOMETHYLENE)BENZOQUINONES." Organic Preparations and Procedures International 30, no. 1 (1998): 90–93. http://dx.doi.org/10.1080/00304949809355264.

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Shurygina, M. P., Yu A. Kurskii, N. O. Druzhkov, et al. "Photolytic decarbonylation of o-benzoquinones." Tetrahedron 64, no. 41 (2008): 9784–88. http://dx.doi.org/10.1016/j.tet.2008.07.008.

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Mahmood, Umar, Vijay K. Kaul, and Leopold Jirovetz. "Alkylated benzoquinones from Iris kumaonensis ☆." Phytochemistry 61, no. 8 (2002): 923–26. http://dx.doi.org/10.1016/s0031-9422(02)00474-0.

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Liao, Chun-Chen, and Rama Krishna Peddinti. "Maskedo-Benzoquinones in Organic Synthesis." Accounts of Chemical Research 35, no. 10 (2002): 856–66. http://dx.doi.org/10.1021/ar000194n.

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De Sousa, Damião P., Ygor W. Vieira, Marciana P. Uliana, Manuela A. Melo, Timothy J. Brocksom, and Sócrates C. H. Cavalcanti. "Larvicidal activity of para-Benzoquinones." Parasitology Research 107, no. 3 (2010): 741–45. http://dx.doi.org/10.1007/s00436-010-1942-7.

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Brehm, Isabella, Sabine Hinneschiedt, and Herbert Meier. "1,4-Benzoquinones with Styryl Substituents." European Journal of Organic Chemistry 2002, no. 18 (2002): 3162–70. http://dx.doi.org/10.1002/1099-0690(200209)2002:18<3162::aid-ejoc3162>3.0.co;2-h.

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Abakumov, G. A., V. K. Cherkasov, T. N. Kocherova, et al. "Functionalization of sterically hindered o-benzoquinones: amino-substituted 3,6-di(tert-butyl)-o-benzoquinones." Russian Chemical Bulletin 56, no. 9 (2007): 1849–56. http://dx.doi.org/10.1007/s11172-007-0287-6.

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