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Articles de revues sur le sujet « Heteroaromatic rings »

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Auteur : Grafiati
Publié le 1 avril 2023

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1

Pitt, William R., David M. Parry, Benjamin G. Perry et Colin R. Groom. « Heteroaromatic Rings of the Future ». Journal of Medicinal Chemistry 52, no 9 (14 mai 2009) : 2952–63. http://dx.doi.org/10.1021/jm801513z.

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2

Doerksen, Robert J., et Ajit J. Thakkar. « Bond orders in heteroaromatic rings ». International Journal of Quantum Chemistry 90, no 2 (2002) : 534–40. http://dx.doi.org/10.1002/qua.998.

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3

Orita, Akihiro, Fangguo Ye, Govindarajulu Babu, Tomohiro Ikemoto et Junzo Otera. « Double elimination protocol for the synthesis of arylene ethynylenes containing heteroaromatic rings ». Canadian Journal of Chemistry 83, no 6-7 (1 juin 2005) : 716–27. http://dx.doi.org/10.1139/v05-038.

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The double elimination reaction of β-substituted sulfones offers a versatile strategy for synthesis of arylene ethynylene kits containing heteroaromatic rings. A sequence of aldol reaction between α-sulfonyl carbanion and aldehyde, trapping the resulting aldolate to give β-substituted sulfone, and double elimination of this intermediate can be integrated in one pot. This protocol allows thiophene, pyridine, and ferrocene units to be accommodated in phenylene ethynylene arrays.Key words: arylene–ethynylenes, heteroaromatic rings, ferrocene, double elimination, sulfones.
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4

Landmana, Marilé, Helmar Görls, Chantelle Crause, Hubert Nienaber, Andrew Olivier et Simon Lotz. « Di-tungsten Bis-carbene Complexes Linked by Condensed Heteroaromatic Spacers ». Zeitschrift für Naturforschung B 62, no 3 (1 mars 2007) : 419–26. http://dx.doi.org/10.1515/znb-2007-0316.

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The 2,7-dilithiated substrates of 3,6-dimethylthieno[3,2-b]thiophene, N,N′-dimethylpyrrolo[3,2- b]pyrrole and N-methylthieno[3,2-b]pyrrole were reacted with W(CO)6 to give, after subsequent alkylation with Et3OBF4, the ditungsten biscarbene complexes [(CO)5W{C(OEt)XXC(OEt)} W(CO)5] (XX = condensed heteroaromatic spacers). Sites of attack during the dilithiation of the condensed rings were studied and compared, and the yields of the desired ditungsten biscarbene complexes optimized by changing the reaction conditions according to the role of the heteroatoms in the rings. The crystallographic data of the three ditungsten biscarbene complexes are reported and their structural features compared. The methyl substituents on the condensed heteroaromatic rings play an important role in determining the molecular configurations.
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5

Doerksen, Robert J., et Ajit J. Thakkar. « Quadrupole and Octopole Moments of Heteroaromatic Rings ». Journal of Physical Chemistry A 103, no 48 (décembre 1999) : 10009–14. http://dx.doi.org/10.1021/jp992524v.

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6

Gamez, Patrick, Tiddo J. Mooibroek, Simon J. Teat et Jan Reedijk. « Anion Binding Involving π-Acidic Heteroaromatic Rings ». Accounts of Chemical Research 40, no 6 (juin 2007) : 435–44. http://dx.doi.org/10.1021/ar7000099.

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7

Katritzky, Alan R., et Nicholas Dennis. « Cycloaddition reactions of heteroaromatic six-membered rings ». Chemical Reviews 89, no 4 (juin 1989) : 827–61. http://dx.doi.org/10.1021/cr00094a006.

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8

Meena, Chhuttan L., Shubdha Ingole, Satyendra Rajpoot, Avinash Thakur, Prajwal P. Nandekar, Abhay T. Sangamwar, Shyam S. Sharma et Rahul Jain. « Discovery of a low affinity thyrotropin-releasing hormone (TRH)-like peptide that exhibits potent inhibition of scopolamine-induced memory impairment in mice ». RSC Advances 5, no 70 (2015) : 56872–84. http://dx.doi.org/10.1039/c5ra06935a.

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9

Thorimbert, Serge, Candice Botuha et Kevin Passador. « ‘Heteroaromatic Rings of the Future’ : Exploration of Unconquered Chemical Space ». Synthesis 51, no 02 (7 novembre 2018) : 384–98. http://dx.doi.org/10.1055/s-0037-1611279.

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William Pitt and co-workers have created a virtual exploratory heterocyclic library ‘VEHICLe’ containing over 200 unconquered bicyclic heteroaromatic rings, synthetically feasible with potential medicinal interest. Since the publication of the 22 ‘heteroaromatic rings of the future’ by Pitt in 2009, 15 of them have been successfully synthesized as bicyclic or polycyclic forms and evaluated for applications in both biology and material science. This short review presents the critical synthesis associated with innovative synthetic methodologies of the synthetically conquered ring scaffolds from the list of 22 with a spotlight on the scientific contribution of this fascinating article for the expansion of the chemical diversity.1 Introduction2 Heteroaromatic Rings of the Future: The Synthetic challenge?2.1 4-Pyrido[1,3]oxazin-4-one-P1 2.2 Pyrrolo[2,1-b][1,3]oxazin-4-one-P4 2.3 Furo[2,1-e]pyridazin-4(1H)-one-P5 2.4 Isoxazolo[3,4-c]pyridin-7-one-P6 2.5 5H,6H-[1,2]Thiazolo[5,4-c]pyridin-5-one-P7 2.6 4H,5H-Furo[3,2-b]pyridin-5-one-P8 2.7 1H,5H,6H-Pyrazolo[3,4-c]pyridin-5-one-P9 2.8 Thieno[3,4-c]pyridazine-P10 2.9 Pyrrolo[1,2-c][1,2,3]triazine-P11 2.10 Thieno[3,4-a]oxazole-P12 2.11 2,4-Dihydropyrrolo[3,2-c]pyrazole-P13 2.12 Pyrazolo[1,5-b]isoxazole-P14 2.13 Imidazo[1,5-c]pyrimidin-3(2H)-one-P16 2.14 Cyclopenta[b][1,4]oxazin-5(4H)-one-P17 2.15 2,3-Dihydro-2,6-naphthyridin-3-one-P18 3 Conclusion
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10

Silva Júnior, P. E., L. C. D. Rezende, Julia Possamai Gimenes, Vinícius Gonçalves Maltarollo, James Dale, G. H. G. Trossini, F. S. Emery et A. Ganesan. « Synthesis of two ‘heteroaromatic rings of the future’ for applications in medicinal chemistry ». RSC Advances 6, no 27 (2016) : 22777–80. http://dx.doi.org/10.1039/c6ra01099g.

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11

Khazaei, Ardeshir, Mohammad Ali Zolfigol, Mohmmad Mokhlesi et Mahtab Pirveysian. « Citric acid as a trifunctional organocatalyst for thiocyanation of aromatic and heteroaromatic compounds in aqueous media ». Canadian Journal of Chemistry 90, no 5 (mai 2012) : 427–32. http://dx.doi.org/10.1139/v2012-013.

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A green and simple procedure for the thiocynation of aromatic and heteroaromatic rings in the presence of a catalytic amount of citric acid in water are described. The reactions proceed in high yields, with short reaction times and under mild conditions.
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12

Angelini, Giancarlo, Cinzia Sparapani et Maurizio Speranza. « Gas-phase heteroaromatic substitution. 7. Methylation of five-membered heteroaromatic rings by free methyl cations ». Journal of the American Chemical Society 112, no 8 (avril 1990) : 3060–63. http://dx.doi.org/10.1021/ja00164a028.

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13

Crestoni, Maria Elisa, Simonetta Fornarini et Maurizio Speranza. « Gas-phase heteroaromatic substitution. 9. Silylation of simple five-membered heteroaromatic rings by trimethylsilyl cations ». Journal of the American Chemical Society 112, no 19 (septembre 1990) : 6929–35. http://dx.doi.org/10.1021/ja00175a029.

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14

Lipshutz, Bruce H. « Five-membered heteroaromatic rings as intermediates in organic synthesis ». Chemical Reviews 86, no 5 (octobre 1986) : 795–819. http://dx.doi.org/10.1021/cr00075a005.

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15

Seo, Jia, Che-Wei Chen, Shih-Ching Chuang, Jung Min Joo, Woohyeong Lee, Ju Eun Jeon et Pei-Ling Chen. « Palladium-Catalyzed C–H Benzannulation of Functionalized Furans and Pyrroles with Alkynes ». Synthesis 53, no 17 (6 mai 2021) : 3001–10. http://dx.doi.org/10.1055/a-1502-3641.

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AbstractA benzannulation strategy involving activation of two C–H bonds of five-membered heteroarenes was developed. Readily available furans and pyrroles stabilized by synthetically useful electron-withdrawing groups underwent Pd-catalyzed 1:2 annulation reactions with diaryl alkynes. A variety of functional groups, including ester, amide, ketone, aldehyde, and nitrile, on the heterocyclic cores were tolerated in the Pd-catalyzed oxidative reactions. In these reactions, the combination of 2,2-dimethylbutyric acid and its conjugate base facilitated metalation at the heteroaromatic rings and reoxidation of the Pd(0) species using oxygen as the terminal oxidant. This strategy provides fluorescent ­benzofuran and indole derivatives and is expected to allow for further development of functionalized polycyclic heteroaromatic compounds.
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16

Kondratov, Ivan S., Oleksandr O. Grygorenko, Oleksandr O. Stepaniuk, Tymofii V. Rudenko, Bohdan V. Vashchenko, Vitalii O. Matvienko et Andrey A. Tolmachev. « Synthesis of Fused Pyridine Carboxylates by Reaction of β-Alkoxyvinyl Glyoxylates with Amino Heterocycles ». Synthesis 52, no 13 (12 mars 2020) : 1915–26. http://dx.doi.org/10.1055/s-0039-1707987.

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An efficient approach to the preparation of pyridine carboxylates fused with 5- or 6-membered heteroaromatic rings is described. The method relied on the Combes-type condensation of the low-molecular­-weight β-alkoxyvinyl glyoxylates as CCC bis-electrophiles and with heteroaromatic amines as NCC binucleophiles. In most experiments­, β-alkoxyvinyl glyoxylates without additional substituent at the β position led to the corresponding α-pyridine carboxylates (67–87% yield). In the case of β-methyl-substituted derivative, γ-pyridine carboxylates were obtained in 84–99% yield. It was found that regio­selectivity of the condensation could be efficiently tuned by changing conditions, such as solvents and acidic additives (HOAc, DMSO or HCl–1,4-dioxane).
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17

Lattelais, M., Y. Ellinger, A. Matrane et J. C. Guillemin. « Looking for heteroaromatic rings and related isomers as interstellar candidates ». Physical Chemistry Chemical Physics 12, no 16 (2010) : 4165. http://dx.doi.org/10.1039/b924574j.

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18

Bejan, Andrei, Dragos Peptanariu, Bogdan Chiricuta, Elena Bicu et Dalila Belei. « Low Molecular Weight Microfibers with Light Sensing Properties ». Materiale Plastice 54, no 4 (30 décembre 2017) : 655–58. http://dx.doi.org/10.37358/mp.17.4.4920.

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Microfibers were obtained from organic low molecular weight compounds based on heteroaromatic and aromatic rings connected by aliphatic spacers. The obtaining of microfibers was proved by scanning electron microscopy. The deciphering of the mechanism of microfiber formation has been elucidated by X-ray diffraction, infrared spectroscopy, and atomic force microscopy measurements. By exciting with light of different wavelength, florescence microscopy revealed a specific optical response, recommending these materials for light sensing applications.
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19

Zhou, Chun-Shan, Ya-Mei Pei et Xiang-Gao Meng. « 2,2′,2′′,2′′′-(3,6-Dioxaoctane-1,8-diyldinitrilo)tetrabenzimidazolium tetrakis(perchlorate) dihydrate ». Acta Crystallographica Section E Structure Reports Online 63, no 11 (17 octobre 2007) : o4334—o4335. http://dx.doi.org/10.1107/s160053680704980x.

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In the title crystal structure, C38H44N10O2 4+·4ClO4 −·2H2O, components are linked into a two-dimensional framework by a combination of N—H...O, C—H...O, O—H...O and N—H...N hydrogen bonds. In addition, weak π–π stacking interactions and anion–π noncovalent interactions between perchlorate anions and heteroaromatic imidazole rings [O...Cg = 3.328 (10) and 3.386 (11) Å; Cg is the centroid of an imidazole ring] consolidate the crystal structure.
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20

Cooper, David L., Stuart C. Wright, Joseph Gerratt et Mario Raimondi. « The electronic structure of heteroaromatic molecules. Part 1. Six-membered rings ». Journal of the Chemical Society, Perkin Transactions 2, no 3 (1989) : 255. http://dx.doi.org/10.1039/p29890000255.

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21

Cooper, David L., Stuart C. Wright, Joseph Gerratt et Mario Raimondi. « The electronic structure of heteroaromatic molecules. Part 2. Five-membered rings ». Journal of the Chemical Society, Perkin Transactions 2, no 3 (1989) : 263. http://dx.doi.org/10.1039/p29890000263.

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22

McKay, Sonya L., Brandy Haptonstall et Samuel H. Gellman. « Beyond the Hydrophobic Effect : Attractions Involving Heteroaromatic Rings in Aqueous Solution1 ». Journal of the American Chemical Society 123, no 6 (février 2001) : 1244–45. http://dx.doi.org/10.1021/ja003256d.

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23

Fraser, Robert R., Tarek S. Mansour et Sylvain Savard. « Acidity measurements in THF. V. Heteroaromatic compounds containing 5-membered rings ». Canadian Journal of Chemistry 63, no 12 (1 décembre 1985) : 3505–9. http://dx.doi.org/10.1139/v85-574.

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The pKa's of 13 heterocyclic aromatic compounds have been measured in tetrahydrofuran (THF) using 13C nmr spectroscopy. The acidifying effect of a nitrogen heteroatom is seen to be quite large (4–6 pK units versus C—H) on an adjacent C—H bond but small on a more remote hydrogen. Most of these aromatic heterocycles are sufficiently acidic, pKa < 34, to be completely deprotonated by lithium tetramethylpiperidide in THF. Benzoxazole appears to be an extremely strong carbon acid, its ring-opened isomer having a pKa of less than 15.7.
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24

Ferreiro, Juan J., Jose G. de la Campa, Angel E. Lozano et Javier de Abajo. « Polyisophthalamides with heteroaromatic pendent rings : Synthesis, physical properties, and water uptake ». Journal of Polymer Science Part A : Polymer Chemistry 43, no 21 (2005) : 5300–5311. http://dx.doi.org/10.1002/pola.21000.

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25

Grenet, Erwann, Ashis Das, Paola Caramenti et Jérôme Waser. « Rhodium-catalyzed C–H functionalization of heteroarenes using indoleBX hypervalent iodine reagents ». Beilstein Journal of Organic Chemistry 14 (25 mai 2018) : 1208–14. http://dx.doi.org/10.3762/bjoc.14.102.

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The C–H indolation of heteroarenes was realized using the benziodoxolone hypervalent iodine reagents indoleBXs. Functionalization of the C–H bond in bipyridinones and quinoline N-oxides catalyzed by a rhodium complex allowed to incorporate indole rings into aza-heteroaromatic compounds. These new transformations displayed complete regioselectivity for the C-6 position of bipyridinones and the C-8 position of quinoline N-oxides and tolerated a broad range of functionalities, such as halogens, ethers, or trifluoromethyl groups.
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Harada, Shinji, Daiki Matsuda, Takahiro Morikawa et Atsushi Nishida. « Direct Synthesis of Enones by Visible-Light-Promoted Oxygenation of Trisubstituted Olefins Using Molecular Oxygen ». Synlett 31, no 14 (18 juin 2020) : 1372–77. http://dx.doi.org/10.1055/s-0040-1707150.

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A one-step synthesis of enones from olefins is described. The reaction was performed under visible-light irradiation in the presence of molecular oxygen and a photocatalyst. The reaction proceeded with various types of trisubstituted olefins to give enones in good yields with high regioselectivity. In particular, oxygen- and nitrogen-containing functional groups, heteroaromatic rings, and cyclopropanes were tolerated. Mechanistic studies and previous reports indicated that the active oxygen species generated in the reaction system is singlet oxygen.
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27

Arai, Tatsuo, et Takuya Kobayashi. « Hydrogen Bonding Induced Highly Selective Isomerization of an Olefin Having Heteroaromatic Rings ». HETEROCYCLES 86, no 2 (2012) : 1129. http://dx.doi.org/10.3987/com-12-s(n)62.

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28

Leach, Andrew G., et Nathan J. Kidley. « Quantitatively Interpreted Enhanced Inhibition of Cytochrome P450s by Heteroaromatic Rings Containing Nitrogen ». Journal of Chemical Information and Modeling 51, no 5 (4 mai 2011) : 1048–63. http://dx.doi.org/10.1021/ci2000506.

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29

Sato, Masaru, Shinsuke Tanaka, Seiji Ebine, Kenichi Morinaga et Sadatoshi Akabori. « Syntheses of ferrocenophanes containing aromatic or heteroaromatic rings in the bridging chain ». Journal of Organometallic Chemistry 289, no 1 (juillet 1985) : 91–95. http://dx.doi.org/10.1016/0022-328x(85)88030-x.

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30

Chmovzh, Timofey N., Timofey A. Kudryashev et Oleg A. Rakitin. « 4,7-Bis(dodecylthio)-[1,2,5]thiadiazolo[3,4-c]pyridine ». Molbank 2021, no 4 (25 octobre 2021) : M1291. http://dx.doi.org/10.3390/m1291.

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Bis(alkylsulfanyl) derivatives of 1,2,5-thiadiazoles fused with aromatic and heteroaromatic rings containing long alkyl chains are of interest as compounds with liquid crystalline properties. In this communication, 4,7-bis(dodecylthio)-[1,2,5]thiadiazolo[3,4-c]pyridine 1 was obtained from 4,7-dibromo-[1,2,5]thiadiazolo[3,4-c]pyridine 2 by a combination of two reactions—aromatic nucleophilic substitution SNAr and Buchwald–Hartwig cross-coupling. The structure of the newly synthesized compounds was established by means of elemental analysis; high-resolution mass spectrometry; 1H, 13C NMR, IR and UV spectroscopy; and mass spectrometry.
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31

Nguyen, Ha Vinh Lam, Walther Caminati et Jens-Uwe Grabow. « The LAM of the Rings : Large Amplitude Motions in Aromatic Molecules Studied by Microwave Spectroscopy ». Molecules 27, no 12 (20 juin 2022) : 3948. http://dx.doi.org/10.3390/molecules27123948.

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Large amplitude motions (LAMs) form a fundamental phenomenon that demands the development of specific theoretical and Hamiltonian models. In recent years, along with the strong progress in instrumental techniques on high-resolution microwave spectroscopy and computational capacity in quantum chemistry, studies on LAMs have become very diverse. Larger and more complex molecular systems have been taken under investigation, ranging from series of heteroaromatic molecules from five- and six-membered rings to polycyclic-aromatic-hydrocarbon derivatives. Such systems are ideally suited to create families of molecules in which the positions and the number of LAMs can be varied, while the heteroatoms often provide a sufficient dipole moment to the systems to warrant the observation of their rotational spectra. This review will summarize three types of LAMs: internal rotation, inversion tunneling, and ring puckering, which are frequently observed in aromatic five-membered rings such as furan, thiophene, pyrrole, thiazole, and oxazole derivatives, in aromatic six-membered rings such as benzene, pyridine, and pyrimidine derivatives, and larger combined rings such as naphthalene, indole, and indan derivatives. For each molecular class, we will present the representatives and summarize the recent insights on the molecular structure and internal dynamics and how they help to advance the field of quantum mechanics.
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32

Guan, Jinming, Christina Spry, Erick T. Tjhin, Penghui Yang, Tanakorn Kittikool, Vanessa M. Howieson, Harriet Ling et al. « Exploring Heteroaromatic Rings as a Replacement for the Labile Amide of Antiplasmodial Pantothenamides ». Journal of Medicinal Chemistry 64, no 8 (1 avril 2021) : 4478–97. http://dx.doi.org/10.1021/acs.jmedchem.0c01755.

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33

Šket, Boris, Marko Zupan, Nataša Zupančič et Barbara Pahor. « Photosubstitution reactions on aromatic and heteroaromatic rings evidence for addition and substitution mechanism ». Tetrahedron 47, no 27 (janvier 1991) : 5029–42. http://dx.doi.org/10.1016/s0040-4020(01)80966-2.

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34

ELNAGDI, M. H., M. R. H. ELMOGHAYER et K. U. SADEK. « ChemInform Abstract : Chemistry of Pyrazoles Condensed to Heteroaromatic Five- and Six- Membered Rings ». ChemInform 22, no 4 (23 août 2010) : no. http://dx.doi.org/10.1002/chin.199104357.

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35

Reibnegger, Gilbert. « An ab initio and density functional theory study on neutral pterin radicals ». Pteridines 26, no 4 (1 décembre 2015) : 135–42. http://dx.doi.org/10.1515/pterid-2015-0008.

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AbstractThe electronic structures of the five radicals resulting from homolytic elimination of one of the hydrogen atoms from the most stable tautomeric form of neutral pterin were investigated in gas phase as well as in aqueous solution. Molecular wave functions obtained by density functional theory were analysed by quantum theory of atoms in molecules and electron localisation functions (ELF). Spin densities of the radicals as well as electrostatic potential functions were analysed. Radicals resulting from elimination of N-bonded hydrogen atoms are more stable in comparison with radicals obtained after abstraction of C-bonded hydrogen atoms. N-centred radicals show strong delocalisation of spin density over both heteroaromatic rings; in C-centred radicals delocalisation does not occur. ELF analyses showed that in N-derived radicals particularly the lone electron pair at N2′ is strongly involved into the bicyclic heteroaromatic π-electron system. Thereby, bonding geometry at N2′ in these radicals changes from pyramidal to planar. Transition from gas phase to solution phase (water) generally leads to increased polarity of the structures. Pterin-derived free radicals have been implicated in several biologically important reactions; so this investigation provides first insights into the detailed electronic structures of such molecular systems.
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36

Sousa, Rui, Narayana Subbiah Hari Narayana Moorthy, Pedro Alexandrino Fernandes, Maria Joao Ramos et Natércia Fernandes Brás. « Binding Mode Prediction and Identification of New Lead Compounds from Natural Products as 3-OST Enzyme Inhibitors ». Letters in Drug Design & ; Discovery 17, no 9 (11 septembre 2020) : 1186–96. http://dx.doi.org/10.2174/1570180817666200313105944.

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Background and Introduction: The availability of antiviral medicines for the treatment of viral diseases is limited, hence the discovery of novel bioactive molecules is required. The present investigation has been carried out to develop novel 3-O-sulfotransferase enzyme inhibitors to treat viral diseases. Method: Virtual screening study (QSAR, docking and pharmacophore analysis) and binding mode analysis have been performed on a dataset collected from the literature (synthetic and natural compounds). Results: The docking studies showed that Glu184, His186, Lys215 and Lys368 residues established the most important hydrogen bonding with several hit compounds. The QSAR results explained that the presence of electronegative atoms/groups in the aromatic or heteroaromatic rings confer increased activity. Furthermore, the flexibility and the aromatic rings with less polar groups have better activity than the compounds connected to purine rings. Finally, the structurebased pharmacophore studies illustrated that the ligand has many polar interaction sites, and the projected acceptor and donor groups in the molecules make a significant contribution to the pharmacophore model building. Conclusion: These studies identified two compounds, Phomoidride B and Barceloneic acid A, as potential 3-OST inhibitors.
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37

Ohta, Akihiro, Tokuhiro Watanabe et Masakatsu Ohta. « Introduction of the C-Substituted into the N-Heteroaromatic Rings Using Alkyl- and Arylmetals ». HETEROCYCLES 24, no 1 (1986) : 265. http://dx.doi.org/10.3987/r-1986-01-0265.

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Chawdhury, N., A. Köhler, R. H. Friend, M. Younus, N. J. Long, P. R. Raithby et J. Lewis. « Synthesis and Electronic Structure of Platinum-Containing Poly-ynes with Aromatic and Heteroaromatic Rings ». Macromolecules 31, no 3 (février 1998) : 722–27. http://dx.doi.org/10.1021/ma971267u.

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Li, Zhun, Yang Wen, Ying Wang et Shaomin Zhu. « Highly transparent and organosoluble polyimides derived from 2,2′-bis[4-(5-amino-2-pyridinoxy) phenyl] propane ». High Performance Polymers 29, no 2 (28 juillet 2016) : 161–69. http://dx.doi.org/10.1177/0954008316632291.

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Two new isomers containing pyridine ring diamine monomers, 2,2′-bis[4-(5-amino-2-pyridinoxy)phenyl] propane (1b) and 2,2′-bis[4-(6-amino-3-pyridinoxy)phenyl] propane (2b), were prepared via a simple nucleophilic reaction of 2-chloro-5-nitropyridine and 5-bromo-2-nitropyridine with bisphenol A in the presence of potassium carbonate, respectively. A series of polyimides (PIs) were obtained from the heterocyclic diamine with various commercially available aromatic dianhydrides via the conventional two-step method. These obtained PIs were investigated in aspects of their solubility, thermal, mechanical, and optical properties for studying the effects of the heteroaromatic rings into the main chain. At the same time, the impact of the two isomers introduced into the PI was discussed in detail.
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Megala, M., et Beulah J. M. Rajkumar. « Heteroaromatic rings as linkers for quercetin-based dye-sensitized solar cell applications : a TDDFT investigation ». Journal of Computational Electronics 18, no 4 (5 octobre 2019) : 1128–38. http://dx.doi.org/10.1007/s10825-019-01398-0.

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Pozzo, Jean-Luc, Vladimir Lokshin, André Samat, Robert Guglielmetti, Roger Dubest et Jean Aubard. « Effect of heteroaromatic annulation with five-membered rings on the photochromism of 2H- [1] -benzopyrans ». Journal of Photochemistry and Photobiology A : Chemistry 114, no 3 (avril 1998) : 185–91. http://dx.doi.org/10.1016/s1010-6030(98)00215-9.

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ROSS GRIMMETT, M. « ChemInform Abstract : Halogenation of Heterocycles : Part III. Heterocycles Fused to Other Aromatic or Heteroaromatic Rings. » ChemInform 25, no 39 (18 août 2010) : no. http://dx.doi.org/10.1002/chin.199439316.

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Kleinpeter, E., R. Spitzner et W. Schroth. « Restricted rotations about exocyclic partial double bonds. The electronic state of heteroaromatic six-membered rings ». Magnetic Resonance in Chemistry 25, no 8 (août 1987) : 688–95. http://dx.doi.org/10.1002/mrc.1260250807.

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Chin, Chong Shik, Yongsun Park et Byeongno Lee. « Regioselective catalytic hydrogenation of nitrogen rings of fused heteroaromatic compounds with an iridium-triphenylphosphine complex ». Catalysis Letters 31, no 2-3 (juin 1995) : 239–43. http://dx.doi.org/10.1007/bf00808836.

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SKET, B., M. ZUPAN, N. ZUPANCIC et B. PAHOR. « ChemInform Abstract : Photosubstitution Reactions on Aromatic and Heteroaromatic Rings. Evidence for Addition and Substitution Mechanism. » ChemInform 22, no 41 (22 août 2010) : no. http://dx.doi.org/10.1002/chin.199141071.

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Liu, K. T., et Y. F. Tuan. « Redetermination of σ+ constants for heteroaromatic rings. Oxygen-17 chemical shifts of trifluoroacetyl substituents and solvolytic reactivities of heteroaromatic analogs of 1-tert-butylbenzyl halides ». Pure and Applied Chemistry 68, no 4 (1 janvier 1996) : 901–6. http://dx.doi.org/10.1351/pac199668040901.

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Guchhait, Sankar Kumar, et Meenu Saini. « Chan–Lam N-arylation and C–H amination with heteroaromatic ring-NH : an approach to access extended-fused imidazo[1,2-a]-pyridines/pyrazines ». New Journal of Chemistry 44, no 2 (2020) : 308–12. http://dx.doi.org/10.1039/c9nj04966e.

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Luh, Tien-Yau, Hsin-Chieh Lin et Chih-Ming Chou. « Heterophenes revisited ». Pure and Applied Chemistry 80, no 3 (1 janvier 2008) : 475–84. http://dx.doi.org/10.1351/pac200880030475.

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By employing the furan annulation protocol, a new series of furan-containing teraryl [n.2]cyclophenes (n = 2-6 and 12) are prepared. These cyclophenes exhibit charge-transfer character in the absorption spectra and unusually large Stokes shifts in the emission spectra. They have neither particularly strong electron-donating moieties nor electron-withdrawing groups, but exhibit unusual second-order nonlinear optical (NLO) properties. The π-systems in teraryl system and in the bridging double bond are highly twisted. Interaction between these twisted π-systems may account for the significant enhancement in hyperpolarizability. Thiophene analog behaved similarly. The five-membered heteroaromatic rings may not only serve as electron donors, but also may accommodate the appropriate geometry to enable the interactions between the oligoaryl systems and the double bond leading to unusual photophysical and NLO properties.
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Pace, Andrea, Silvestre Buscemi et Nicolò Vivona. « THE SYNTHESIS OF FLUORINATED HETEROAROMATIC COMPOUNDS. PART 2. FIVE-MEMBERED RINGS WITH TWO HETEROATOMS. A REVIEW ». Organic Preparations and Procedures International 39, no 1 (février 2007) : 1–70. http://dx.doi.org/10.1080/00304940709458581.

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Hicks, Martin G., Gurnos Jones et David C. York. « Intramolecular nitrene insertions into aromatic and heteroaromatic rings. Part 8. Flash vacuum pyrolysis of 2-azidobenzylpyridines ». Journal of the Chemical Society, Perkin Transactions 1, no 1 (1988) : 69. http://dx.doi.org/10.1039/p19880000069.

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