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Artículos de revistas sobre el tema "Aromatic Nitrogen-heterocycles"

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Publicado: 18 de mayo de 2024

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1

Zong, He-Hou, Chuang Yao, Chang Q. Sun, Jian-Guo Zhang y Lei Zhang. "Structure and Stability of Aromatic Nitrogen Heterocycles Used in the Field of Energetic Materials". Molecules 25, n.º 14 (15 de julio de 2020): 3232. http://dx.doi.org/10.3390/molecules25143232.

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Understanding the stabilization of nitrogen heterocycles is critical in the field of energetic materials and calls for innovative knowledge of nitrogen aromatics. Herewith, we report for the first time that nitrogen lone pair electron (NLPE) delocalization in five-membered nitrogen heterocycles creates a second σ-aromaticity in addition to the prototypical π-aromaticity. The NLPE delocalization and the attendant dual-aromaticity are enhanced as more carbon atoms in the ring are substituted by unsaturated nitrogen atoms. The presence of adjacent nitrogen atoms in the ring can enhance the aromaticity of the nitrogen heterocycles and improve in-crystal intermolecular binding strength but will decrease the firmness of the individual molecular architecture. Notably, such σ-aromaticity is not present in six-membered nitrogen heterocycles, probably due to the longer bonds and broader regions of their rings; therefore, six-membered heterocycles present overall lower aromaticity than five-membered heterocycles. This work brings new knowledge to nitrogen aromatics and is expected to inspire broad interest in the chemistry community.
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2

Palumbo Piccionello, Antonio. "Editorial for Special Issue “Bioactive Oxadiazoles”". International Journal of Molecular Sciences 22, n.º 8 (13 de abril de 2021): 3988. http://dx.doi.org/10.3390/ijms22083988.

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3

Palumbo Piccionello, Antonio. "Bioactive Oxadiazoles 2.0". International Journal of Molecular Sciences 23, n.º 7 (31 de marzo de 2022): 3841. http://dx.doi.org/10.3390/ijms23073841.

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4

Cervenka, Jiri, Akin Budi, Nikolai Dontschuk, Alastair Stacey, Anton Tadich, Kevin J. Rietwyk, Alex Schenk et al. "Graphene field effect transistor as a probe of electronic structure and charge transfer at organic molecule–graphene interfaces". Nanoscale 7, n.º 4 (2015): 1471–78. http://dx.doi.org/10.1039/c4nr05390g.

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5

Sachar, Anand, Poonam Gupta, Shallu Gupta y R. L. Sharma. "A novel approach towards the synthesis of tricyclic systems based on pyridine, pyran, thiopyran, azepine, oxepin, thiepin, and pyrimidine rings under different solvent conditions". Canadian Journal of Chemistry 88, n.º 5 (mayo de 2010): 478–84. http://dx.doi.org/10.1139/v10-015.

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6

Steel, Peter J. "Aromatic nitrogen heterocycles as bridging ligands; a survey". Coordination Chemistry Reviews 106 (noviembre de 1990): 227–65. http://dx.doi.org/10.1016/0010-8545(60)80005-7.

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7

Savić, Nada D., Dusan R. Milivojevic, Biljana Đ. Glišić, Tatjana Ilic-Tomic, Jovana Veselinovic, Aleksandar Pavic, Branka Vasiljevic, Jasmina Nikodinovic-Runic y Miloš I. Djuran. "A comparative antimicrobial and toxicological study of gold(iii) and silver(i) complexes with aromatic nitrogen-containing heterocycles: synergistic activity and improved selectivity index of Au(iii)/Ag(i) complexes mixture". RSC Advances 6, n.º 16 (2016): 13193–206. http://dx.doi.org/10.1039/c5ra26002g.

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Combination therapy may be applied in the case of gold(iii) and silver(i) complexes with aromatic nitrogen-containing heterocycles to improve their antimicrobial activity and reduce toxic-side effects.
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8

McGuire, Brett A., Andrew M. Burkhardt, Sergei Kalenskii, Christopher N. Shingledecker, Anthony J. Remijan, Eric Herbst y Michael C. McCarthy. "Detection of the aromatic molecule benzonitrile (c-C6H5CN) in the interstellar medium". Science 359, n.º 6372 (11 de enero de 2018): 202–5. http://dx.doi.org/10.1126/science.aao4890.

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Polycyclic aromatic hydrocarbons and polycyclic aromatic nitrogen heterocycles are thought to be widespread throughout the universe, because these classes of molecules are probably responsible for the unidentified infrared bands, a set of emission features seen in numerous Galactic and extragalactic sources. Despite their expected ubiquity, astronomical identification of specific aromatic molecules has proven elusive. We present the discovery of benzonitrile (c-C6H5CN), one of the simplest nitrogen-bearing aromatic molecules, in the interstellar medium. We observed hyperfine-resolved transitions of benzonitrile in emission from the molecular cloud TMC-1. Simple aromatic molecules such as benzonitrile may be precursors for polycyclic aromatic hydrocarbon formation, providing a chemical link to the carriers of the unidentified infrared bands.
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9

He, Jiwen, Xingguo Zhang, Qiuqin He, Hao Guo y Renhua Fan. "Synthesis of 15N-labeled heterocycles via the cleavage of C–N bonds of anilines and glycine-15N". Chemical Communications 57, n.º 44 (2021): 5442–45. http://dx.doi.org/10.1039/d1cc01734a.

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10

Glišić, Biljana Đ., Ivana Aleksic, Peter Comba, Hubert Wadepohl, Tatjana Ilic-Tomic, Jasmina Nikodinovic-Runic y Miloš I. Djuran. "Copper(ii) complexes with aromatic nitrogen-containing heterocycles as effective inhibitors of quorum sensing activity in Pseudomonas aeruginosa". RSC Advances 6, n.º 89 (2016): 86695–709. http://dx.doi.org/10.1039/c6ra19902j.

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Copper(ii) complexes with aromatic nitrogen-containing heterocycles are a new class of quorum sensing inhibitors that attenuate virulence without a pronounced effect on the bacterial growth, thus offering a lower risk for resistance development.
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11

Campos, Joana F. y Sabine Berteina-Raboin. "Tandem Catalysis: Synthesis of Nitrogen-Containing Heterocycles". Catalysts 10, n.º 6 (5 de junio de 2020): 631. http://dx.doi.org/10.3390/catal10060631.

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In this Review, we consider all the publications since the beginning of the century that describe tandem reactions resulting in the formation of five-membered aromatic nitrogen heterocycles (thiazole, imidazole, indole, tetrazole, triazole, and isoxazole). The contents of this review are organized by taxonomy and type of tandem catalysis. It covers orthogonal, auto-, and assisted tandem catalysis, providing an overview of tandem reactions applied tonitrogen heterocycles reported in the literature up to March 2020. We believe that this compilation of data will provide a necessary starting reference to developthe applications of tandem catalysis in medicinal chemistry.
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12

Gonda, Jozef, Pavol Kristian y Ľubomír Mikler. "Synthesis of isothiocyanates from non-aromatic nitrogen-containing heterocycles". Collection of Czechoslovak Chemical Communications 51, n.º 1 (1986): 112–17. http://dx.doi.org/10.1135/cccc19860112.

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Investigation of the reaction of thiophosgene with Δ2-oxazolines I, Δ3-thiazolines II, 4H-benzo[d][1,3]thiazines III, 2-methoxypentahydro-Δ1-azepine IV, theophylline and caffeine showed that only compounds I and IV reacted to give 2-acyloxyethyl isothiocyanates and methyl 6-isothiocyanatohexanoate. The structure of these products was corroborated by IR, 1H NMR, 13C NMR and mass spectral methods. The suitability of the above-mentioned compounds to react is discussed.
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13

Tai, Julia C., Linrong Yang y Norman L. Allinger. "Molecular mechanics (MM3). Calculations on nitrogen-containing aromatic heterocycles". Journal of the American Chemical Society 115, n.º 25 (diciembre de 1993): 11906–17. http://dx.doi.org/10.1021/ja00078a032.

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14

Kojima, Hideo, Noboru Matsumura y Hiroo Inoue. "Preparation of nitrogen heterocycles from aromatic amines using tris(isopropylthio)cyclopropenyl cation as a three-carbon building block". Canadian Journal of Chemistry 70, n.º 1 (1 de enero de 1992): 1–4. http://dx.doi.org/10.1139/v92-001.

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Quinolines (2 and 3) and naphthazepines (8 and 9) are prepared in high yields by the reaction of tris(isopropylthio)-cyclopropenylium perchlorate (1) with anilines and 1-naphthylamines, respectively, under nitrogen in N,N-dimethylformamide at 80–85 °C. The reactions are proven to proceed through the intermediary formation of iminium salts (5, 10, and 11) derived from 1 and amines. The reaction of 1 with pyrrole and indole in dimethyl sulfoxide, containing sodium hydride, at 25 °C gives 5,6,7-tris(isopropylthio)-1H-pyrrolizine (12) and 1,2,3-tris(isopropylthio)-9H-fluorazene (14), respectively, in high yields by intramolecular cyclization of a vinylcarbene intermediate. The possible pathway for the formation of these nitrogen heterocycles is proposed. Keywords: cyclopropenyl cation, aromatic amines, nitrogen heterocycles, three-carbon building block.
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15

Campos, Joana F. y Sabine Berteina-Raboin. "Greener Synthesis of Nitrogen-Containing Heterocycles in Water, PEG, and Bio-Based Solvents". Catalysts 10, n.º 4 (14 de abril de 2020): 429. http://dx.doi.org/10.3390/catal10040429.

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The solvents used in chemistry are a fundamental element of the environmental performance of processes in corporate and academic laboratories. Their influence on costs, health safety, and nature cannot be neglected. Quantitatively, solvents are the most abundant constituents of chemical transformations; therefore, acting on solvents and replacing standard solvents with safer products can have a great ecological impact. However, not all green solvents are suitable for the wide scope of organic chemistry reactions. A second point to consider is that 50% of pharmaceutical drugs are nitrogen heterocycles compounds. It therefore appeared important to provide an overview of the more ecological methodologies for synthesizing this class of compounds. In this review, all publications since 2000 that describe green reactions leading to the formation of nitrogen heterocycles using safe solvents were considered. We chose water, PEG, and bio-based solvents for their negligible toxicity. The synthesis of five-, six-, and seven-membered aromatic nitrogen heterocycles using green reactions reported in the literature to date is described.
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16

Bosdet, Michael J. D. y Warren E. Piers. "B-N as a C-C substitute in aromatic systems". Canadian Journal of Chemistry 87, n.º 1 (1 de enero de 2009): 8–29. http://dx.doi.org/10.1139/v08-110.

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The substitution of isoelectronic B–N units for C–C units in aromatic hydrocarbons produces novel heterocycles with structural similarities to the all-carbon frameworks, but with fundamentally altered electronic properties and chemistry. Since the pioneering work of Dewar some 50 years ago, the relationship between B–N and C–C and the wealth of parent all-carbon aromatics has captured the imagination of organic, inorganic, materials, and computational chemists alike, particularly in recent years. New applications in biological chemistry, new materials, and novel ligands for transition-metal complexes have emerged from these studies. This review is aimed at surveying activity in the area in the past couple of decades. Its organization is based on ring size and type of the all-carbon or heterocyclic subunit that the B–N analog is derived from. Structural aspects pertaining to the retention of aromaticity are emphasized, along with delineation of significant differences in physical properties of the B–N compound as compared to the C–C parent.Key words: boron-nitrogen heterocycles, aromaticity, organic materials, main-group chemistry.
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17

Kočí, Kamila, Hana Petrovská, Zdeněk Šimek, Elena VaraĎová y Andrea Syslová. "Extraction of polycyclic aromatic nitrogen heterocycles from spiked soil samples". International Journal of Environmental Analytical Chemistry 87, n.º 2 (15 de febrero de 2007): 111–23. http://dx.doi.org/10.1080/03067310600947276.

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18

Zauer, E. A. "Enthalpy of formation of five-membered nitrogen-containing aromatic heterocycles". Russian Journal of General Chemistry 85, n.º 10 (octubre de 2015): 2268–76. http://dx.doi.org/10.1134/s1070363215100084.

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19

STEEL, P. J. "ChemInform Abstract: Aromatic Nitrogen Heterocycles as Bridging Ligands. A Survey". ChemInform 22, n.º 9 (23 de agosto de 2010): no. http://dx.doi.org/10.1002/chin.199109363.

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20

Ruckmick, Stephen C. y Robert J. Hurtubise. "Class separation of polycyclic aromatic hydrocarbons, nitrogen heterocycles and hydroxyl aromatics by liquid chromatography". Journal of Chromatography A 331 (enero de 1985): 55–68. http://dx.doi.org/10.1016/0021-9673(85)80006-6.

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21

Kochany, J. y R. J. Maguire. "Abiotic transformations of polynuclear aromatic hydrocarbons and polynuclear aromatic nitrogen heterocycles in aquatic environments". Science of The Total Environment 144, n.º 1-3 (abril de 1994): 17–31. http://dx.doi.org/10.1016/0048-9697(94)90424-3.

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22

Fraser, Robert R., Tarek S. Mansour y Sylvain Savard. "Acidity measurements in THF. V. Heteroaromatic compounds containing 5-membered rings". Canadian Journal of Chemistry 63, n.º 12 (1 de diciembre de 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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23

de la Torre, Beatriz G. y Fernando Albericio. "The Pharmaceutical Industry in 2020. An Analysis of FDA Drug Approvals from the Perspective of Molecules". Molecules 26, n.º 3 (25 de enero de 2021): 627. http://dx.doi.org/10.3390/molecules26030627.

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Although the pharmaceutical industry will remember 2020 as the year of COVID-19, it is important to highlight that this year has been the second-best—together with 1996—in terms of the number of drugs accepted by the US Food and Drug Administration (FDA). Each of these two years witnessed the authorization of 53 drugs—a number surpassed only in 2018 with 59 pharmaceutical agents. The 53 approvals in 2020 are divided between 40 new chemical entities and 13 biologic drugs (biologics). Of note, ten monoclonal antibodies, two antibody–drug conjugates, three peptides, and two oligonucleotides have been approved in 2020. Close inspection of the so-called small molecules reveals the significant presence of fluorine atoms and/or nitrogen aromatic heterocycles. This report analyzes the 53 new drugs of the 2020 harvest from a strictly chemical perspective, as it did for those authorized in the previous four years. On the basis of chemical structure alone, the drugs that received approval in 2020 are classified as the following: biologics (antibodies, antibody-drug conjugates, and proteins); TIDES (peptide and oligonucleotides); natural products; fluorine-containing molecules; nitrogen aromatic heterocycles; and other small molecules.
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24

He, Ling, Yan Jiang, Guo-Chuan Zhou, Guang-Li He, Ju-Lian Li y Shi-Long Zheng. "Ruthenium(II)-Porphyrin Catalyzed Selective N-Imidation of Aromatic Nitrogen Heterocycles". Synthesis 2007, n.º 10 (2 de mayo de 2007): 1459–64. http://dx.doi.org/10.1055/s-2007-966048.

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25

Nobeli, I., S. L. Price, J. P. M. Lommerse y R. Taylor. "Hydrogen bonding properties of oxygen and nitrogen acceptors in aromatic heterocycles". Journal of Computational Chemistry 18, n.º 16 (diciembre de 1997): 2060–74. http://dx.doi.org/10.1002/(sici)1096-987x(199712)18:16<2060::aid-jcc10>3.0.co;2-s.

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26

TAI, J. C., L. YANG y N. L. ALLINGER. "ChemInform Abstract: Molecular Mechanics (MM3). Calculations on Nitrogen-Containing Aromatic Heterocycles". ChemInform 25, n.º 12 (19 de agosto de 2010): no. http://dx.doi.org/10.1002/chin.199412035.

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27

Jadhav, Sushilkumar. "Synthesis of fluorescent long-chain thiols/disulfides as building-blocks for self-assembled monolayers preparation". Open Chemistry 10, n.º 2 (1 de abril de 2012): 295–99. http://dx.doi.org/10.2478/s11532-011-0140-5.

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AbstractNew symmetrical disulfides together with the corresponding thiols bearing fluorescent end-groups have been synthesized as building-blocks for self-assembled monolayers (SAMs). The synthesis has been accomplished starting from aromatic nitrogen heterocycles in three steps. The conversion of the tosylated intermediate into the final disulfide is accomplished by use of sodium hydrogen sulfide (NaSH). Both products (thiols and disulfides) were isolated and characterized.
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28

Frühauf, Anton, Martin Behringer y Franz-Josef Meyer-Almes. "Significance of Five-Membered Heterocycles in Human Histone Deacetylase Inhibitors". Molecules 28, n.º 15 (27 de julio de 2023): 5686. http://dx.doi.org/10.3390/molecules28155686.

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Five-membered heteroaromatic rings, in particular, have gained prominence in medicinal chemistry as they offer enhanced metabolic stability, solubility and bioavailability, crucial factors in developing effective drugs. The unique physicochemical properties and biological effects of five-membered heterocycles have positioned them as key structural motifs in numerous clinically effective drugs. Hence, the exploration of five-ring heterocycles remains an important research area in medicinal chemistry, with the aim of discovering new therapeutic agents for various diseases. This review addresses the incorporation of heteroatoms such as nitrogen, oxygen and sulfur into the aromatic ring of these heterocyclic compounds, enhancing their polarity and facilitating both aromatic stacking interactions and the formation of hydrogen bonds. Histone deacetylases are present in numerous multiprotein complexes within the epigenetic machinery and play a central role in various cellular processes. They have emerged as important targets for cancer, neurodegenerative diseases and other therapeutic indications. In histone deacetylase inhibitors (HDACi’s), five-ring heterocycles perform various functions as a zinc-binding group, a linker or head group, contributing to binding activity and selective recognition. This review focuses on providing an up-to-date overview of the different five-membered heterocycles utilized in HDACi motifs, highlighting their biological properties. It summarizes relevant publications from the past decade, offering insights into the recent advancements in this field of research.
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29

Li, Chongyang, Yongli Huang, Chang Q. Sun y Lei Zhang. "Acidic Stabilization of the Dual-Aromatic Heterocyclic Anions". Catalysts 11, n.º 7 (24 de junio de 2021): 766. http://dx.doi.org/10.3390/catal11070766.

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Recently, we discovered that the delocalization of nitrogen lone-pair electrons (NLPEs) in five-membered nitrogen heterocycles created a second σ-aromaticity in addition to the prototypical π-aromaticity. Such dual-aromatic compounds, such as the pentazole anion, were proved to have distinct chemistry in comparison to traditional π-aromatics, such as benzene, and were surprisingly unstable, susceptible to electrophilic attack, and relatively difficult to obtain. The dual-aromatics are basic in nature, but prefer not to be protonated when confronting more than three hydronium/ammonium ions, which violates common sense understanding of acid−base neutralization for a reason that is unclear. Here, we carried out 63 test simulations to explore the stability and reactivity of three basic heterocycle anions (pentazole anion N5¯, tetrazole anion N4C1H1¯, and 1,2,4-triazole anion N3C2H2¯) in four types of solvents (acidic ions, H3O+ and NH4+, polar organics, THF, and neutral organics, benzene) with different acidities and concentrations. By quantum mechanical calculations of the electron density, atomistic structure, interatomic interactions, molecular orbital, magnetic shielding, and energetics, we confirmed the presence of dual aromaticity in the heterocyclic anions, and discovered their reactivity to be a competition between their basicity and dual aromaticity. Interestingly, when the acidic ions H3O+/NH4+ are three times more in number than the basic heterocyclic anions, the anions turn to violate acid−base neutralization and remain unprotonated, and the surrounding acidic ions start to show a significant stabilization effect on the studied heterocyclic anions. This work brings new knowledge to nitrogen aromatics and the finding is expected to be adaptable for other pnictogen five-membered ring systems.
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30

Oliveira, Ricardo R., Germán Molpeceres, Felipe Fantuzzi, Heidy M. Quitián-Lara, Heloisa M. Boechat-Roberty y Johannes Kästner. "Gas-phase spectroscopic characterization of neutral and ionic polycyclic aromatic phosphorus heterocycles (PAPHs)". Monthly Notices of the Royal Astronomical Society 500, n.º 2 (7 de noviembre de 2020): 2564–76. http://dx.doi.org/10.1093/mnras/staa3460.

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ABSTRACT Polycyclic aromatic hydrocarbons (PAHs) constitute an essential family of compounds in interstellar (ISM) and circumstellar (CSM) media. Recently, formation routes for the corresponding polycyclic aromatic phosphorus heterocycles (PAPHs) in astrophysical environments have been proposed. In order to contribute to a better understanding of the phosphorus chemistry in the ISM, infrared (IR) spectra and selected properties of PAPHs were computed at the density functional theory level for neutral, cationic, and anionic species. Our results reveal that several protonated PAPHs do not have planar backbones, and all species have permanent dipole moments between 2D and 4D. Closed-shell PAPHs have similar ionization potentials compared to the parent PAHs, below the Lyman threshold limit. In addition, all PAPHs show positive electron affinities higher than those of PAHs. Protonation preferably occurs on the heteroatom but with lower proton affinities than those of the corresponding nitrogen analogues (polycyclic aromatic nitrogen heterocycles). In general, neutral species have similar IR spectra profile with the most intense bands around 800 cm−1 (12.5 μm) related to C−H wagging. Charge and protonation affect the IR spectra mainly by decreasing the intensities of these modes and increasing the ones between 1000 (10.0 μm) and 1800 cm−1 (5.6 μm). The P−H stretching appears in a different spectral region, between 2300 (4.3 μm) and 2700 cm−1 (3.7 μm). Our results are discussed in the context of distinct sources where PAHs and phosphorus are detected. PAPHs, in particular the coronene derivatives, can contribute to the unidentified infrared emission band at 6.2 μm.
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31

Vlocskó, R. Bernadett, Guoshu Xie y Béla Török. "Green Synthesis of Aromatic Nitrogen-Containing Heterocycles by Catalytic and Non-Traditional Activation Methods". Molecules 28, n.º 10 (17 de mayo de 2023): 4153. http://dx.doi.org/10.3390/molecules28104153.

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Recent advances in the environmentally benign synthesis of aromatic N-heterocycles are reviewed, focusing primarily on the application of catalytic methods and non-traditional activation. This account features two main parts: the preparation of single ring N-heterocycles, and their condensed analogs. Both groups include compounds with one, two and more N-atoms. Due to the large number of protocols, this account focuses on providing representative examples to feature the available methods.
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32

Velihina, Yevheniia, Nataliya Obernikhina, Stepan Pilyo, Maryna Kachaeva, Oleksiy Kachkovsky y Volodymyr Brovarets. "In silico study of binding affinity of nitrogenous bicyclic heterocycles: fragment-to-fragment approach". Ukr. Bioorg. Acta 2020, Vol. 15, N2 15, n.º 2 (30 de diciembre de 2020): 49–59. http://dx.doi.org/10.15407/bioorganica2020.02.049.

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The binding affinity of model aromatic amino acids and heterocycles and their derivatives condensed with pyridine were investigated in silico and are presented in the framework of fragment-to-fragment approach. The presented model describes interaction between pharmacophores and biomolecules. Scrupulous data analysis shows that expansion of the π-electron system by heterocycles annelation causes the shifting up of high energy levels, while the appearance of new the dicoordinated nitrogen atom is accompanied by decreasing of the donor-acceptor properties. Density Functional Theory (DFT) wB97XD/6-31(d,p)/calculations of π-complexes of the heterocycles 1-3 with model fragments of aromatic amino acids, which were formed by π-stack interaction, show an increase in the stabilization energy of π-complexes during the moving from phenylalanine to tryptophan. DFT calculation of pharmacophore complexes with model proton-donor amino acid by the hydrogen bonding mechanism (H-B complex) shows that stabilization energy (DE) increases from monoheterocycles to their condensed derivatives. The expansion of the π-electron system by introducing phenyl radicals to the oxazole cycle as reported earlier [18] leads to a decrease in the stabilization energy of the [Pharm-BioM] complexes in comparison with the annelated oxazole by the pyridine cycle.
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33

Mattioda, A. L., D. M. Hudgins, C. W. Bauschlicher, M. Rosi y L. J. Allamandola. "Infrared Spectroscopy of Matrix-Isolated Polycyclic Aromatic Compounds and Their Ions. 6. Polycyclic Aromatic Nitrogen Heterocycles". Journal of Physical Chemistry A 107, n.º 10 (marzo de 2003): 1486–98. http://dx.doi.org/10.1021/jp021938c.

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34

Švábenský, Radim, Kamila Kočí y Zdeněk Šimek. "The study of properties of HPLC determination of polycyclic aromatic nitrogen heterocycles". International Journal of Environmental Analytical Chemistry 87, n.º 5 (20 de abril de 2007): 337–49. http://dx.doi.org/10.1080/03067310601087130.

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35

Itoh, Nobuya, Yoshikazu Izumi y Hideaki Yamada. "Haloperoxidase-catalyzed halogenation of nitrogen-containing aromatic heterocycles represented by nucleic bases". Biochemistry 26, n.º 1 (13 de enero de 1987): 282–89. http://dx.doi.org/10.1021/bi00375a039.

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36

Austin, Martin, Kassu Gebreyes, Henry G. Kuivila, Kamal Swami y Jon A. Zubieta. "Complexes of bis-(chlorodimethylstannyl)- and bis(dichloromethylstannyl)methanes with aromatic nitrogen heterocycles". Organometallics 6, n.º 4 (abril de 1987): 834–42. http://dx.doi.org/10.1021/om00147a024.

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37

Lopyrev, V. A., T. N. Kashik, T. G. Ermakova, E. I. Brodskaya, L. G. Kolzunova y N. Ya Kovarskii. "Electrochemically initiated polymerization of vinyl-substituted five-membered nitrogen-containing aromatic heterocycles". Polymer Science U.S.S.R. 32, n.º 1 (enero de 1990): 150–54. http://dx.doi.org/10.1016/0032-3950(90)90062-b.

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38

Beveridge, Ramsay E., Daniel A. Black y Bruce A. Arndtsen. "Copper-Catalyzed Multicomponent Coupling of Organoindium Reagents with Nitrogen-Containing Aromatic Heterocycles". European Journal of Organic Chemistry 2010, n.º 19 (14 de mayo de 2010): 3650–56. http://dx.doi.org/10.1002/ejoc.201000231.

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39

Ahamed, Muneer y Matthew H. Todd. "Catalytic Asymmetric Additions of Carbon-Centered Nucleophiles to Nitrogen-Containing Aromatic Heterocycles". European Journal of Organic Chemistry 2010, n.º 31 (3 de septiembre de 2010): 5935–42. http://dx.doi.org/10.1002/ejoc.201000877.

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40

Ignatovich, Zh V. "Synthesis of chimeric amides of 2-arilaminopyrimidine series". Proceedings of the National Academy of Sciences of Belarus, Chemical Series 56, n.º 2 (7 de junio de 2020): 166–80. http://dx.doi.org/10.29235/1561-8331-2020-56-2-38-166-180.

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Methodological approaches to the synthesis of 2-arylpyrimidine amides with predicted antitumor activity using the design of chimeric molecules by combining pharmacophore fragments of known antitumor drugs are considered. The results of the synthesis of chimeric amides containing, along with the 2-amino-pyrimidine fragment, fragments of other nitrogen and oxygen-containing heterocycles (piperazine, morpholine, isoxazole, etc.), aromatic cycles (benzene, methylnitroaniline, phenylenediamine) and functional (methyl-, amino-, carboxy-, etc.) groups in different positions of the molecule, are presented.
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41

Piguel, Sandrine, Marius Mamone, Jessy Aziz y Julie Le Bescont. "Aminocarbonylation of N-Containing Heterocycles with Aromatic Amines Using Mo(CO)6". Synthesis 50, n.º 07 (18 de enero de 2018): 1521–26. http://dx.doi.org/10.1055/s-0037-1609152.

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We describe herein the palladium-catalyzed aminocarbonylation of nitrogen-containing heterocycles with aniline derivatives using molybdenum hexacarbonyl as a CO solid source, expanding the scope of the limited examples. This method is compatible with a variety of substitutions on the aniline moiety. The simple reaction conditions include easily available Pd(dppf)Cl2 catalyst, DBU as base in DMF at 120 °C for 3 hours in sealed tube thereby leading to the isolation of 21 compounds with yields ranging from 18 to 82%. We also show that double aminocarbonylation reactions are possible in satisfactory yields regarding both coupling partners.
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42

Zeng, Qun, Yanyang Qu, Jinshan Li y Hui Huang. "A DFT study of five-membered nitrogen-containing fused heterocycles for insensitive highly energetic materials". RSC Advances 6, n.º 80 (2016): 77005–12. http://dx.doi.org/10.1039/c6ra11624h.

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43

Cheng, Yi, Junfang Mao, Zhe Bai, Wei Zhang, Linyuan Zhang, Hui Chen, Lina Wang, Ling Li y Jianmin Chen. "The Significant Contribution of Polycyclic Aromatic Nitrogen Heterocycles to Light Absorption in the Winter North China Plain". Sustainability 15, n.º 11 (25 de mayo de 2023): 8568. http://dx.doi.org/10.3390/su15118568.

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By quantifying the absorption of black carbon (BC), brown carbon (BrC) and the lensing effect, we found that BrC dominates the total absorption at 450 nm, and the largest absorption contribution proportion of BrC could reach 78.3% during heavy pollution. The average absorption enhancement (Eabs) at 530 nm was only 1.38, indicating that BC is not coated well here. The average value of the absorption Ångstrom exponent (AAE) between 450 nm and 530 nm was 5.3, suggesting a high concentration of BrC in Wangdu. CHN+ was the greatest contributor to the light absorption of molecules detected in MSOC with a proportion of 12.2–22.4%, in which the polycyclic aromatic nitrogen heterocycles (PANHs) were the dominant compounds. The C6H5NO3 and its homologous series accounted for 3.0–11.3%, and the C15H9N and its homologous series, including one C16H11N and three C17H13N compounds, accounted for 5.1–12.3%. The absorption of these PANHs is comparable to that of nitro–aromatics, which should attract more attention to the impact of climate radiative forcing.
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44

de la Torre, Beatriz G. y Fernando Albericio. "The Pharmaceutical Industry in 2021. An Analysis of FDA Drug Approvals from the Perspective of Molecules". Molecules 27, n.º 3 (5 de febrero de 2022): 1075. http://dx.doi.org/10.3390/molecules27031075.

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Similar to last year, 2021 will be remembered for the COVID-19 pandemic. Although five vaccines have been approved by the two most important drug regulatory agencies, namely the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA), the pandemic has still not been brought under control. However, despite the context of a global pandemic, 2021 has been an excellent year with respect to drug approvals by the FDA. In 2021, 50 drugs have been authorized, making it the fourth-best year after 2018 (59 drugs) and 1996 and 2020 (53 each). Regarding biologics, 2021 has been the third-best year to date, with 14 approvals, and it has also witnessed the authorization of 36 small molecules. Of note, nine peptides, eight monoclonal antibodies, two antibody-drug conjugates, and two oligonucleotides have been approved this year. From them, five of the molecules are pegylated and three of them highly pegylated. The presence of nitrogen aromatic heterocycles and/or fluorine atoms are once again predominant among the so-called small molecules. This report analyzes the 50 new drugs approved in 2021 from a chemical perspective, as it did for those authorized in the previous five years. On the basis of chemical structure alone, the drugs that received approval in 2021 are classified as the following: biologics (antibodies, antibody-drug conjugates, enzymes, and pegylated proteins); TIDES (peptide and oligonucleotides); combined drugs; natural products; nitrogen aromatic heterocycles; fluorine-containing molecules; and other small molecules.
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45

Ma, Yecheng, Jinxiu Wang, Yang Liu, Xinyue Wang, Binglin Zhang, Wei Zhang, Tuo Chen, Guangxiu Liu, Lingui Xue y Xiaowen Cui. "Nocardioides: “Specialists” for Hard-to-Degrade Pollutants in the Environment". Molecules 28, n.º 21 (5 de noviembre de 2023): 7433. http://dx.doi.org/10.3390/molecules28217433.

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Nocardioides, a genus belonging to Actinomycetes, can endure various low-nutrient conditions. It can degrade pollutants using multiple organic materials such as carbon and nitrogen sources. The characteristics and applications of Nocardioides are described in detail in this review, with emphasis on the degradation of several hard-to-degrade pollutants by using Nocardioides, including aromatic compounds, hydrocarbons, haloalkanes, nitrogen heterocycles, and polymeric polyesters. Nocardioides has unique advantages when it comes to hard-to-degrade pollutants. Compared to other strains, Nocardioides has a significantly higher degradation rate and requires less time to break down substances. This review can be a theoretical basis for developing Nocardioides as a microbial agent with significant commercial and application potential.
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46

Antuf’eva, A. D., M. V. Dmitriev, O. A. Maiorova, I. G. Mokrushin, A. R. Galeev, E. V. Shklyaeva y G. G. Abashev. "New π-Conjugated Ferrocenyl-Substituted Heterocyclic Systems Containing Electron-Deficient Aromatic Nitrogen Heterocycles". Russian Journal of Organic Chemistry 54, n.º 9 (septiembre de 2018): 1350–57. http://dx.doi.org/10.1134/s1070428018090142.

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47

Acree, William E. "Polycyclic Aromatic Nitrogen Heterocycles. Solubility of Carbazole in Binary Solvent Mixtures Containing Cyclohexane". Physics and Chemistry of Liquids 22, n.º 3 (diciembre de 1990): 157–62. http://dx.doi.org/10.1080/00319109008028805.

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48

Mattioda, A. L., C. W. Bauschlicher, A. Ricca, J. Bregman, D. M. Hudgins y L. J. Allamandola. "Infrared spectroscopy of matrix-isolated neutral polycyclic aromatic nitrogen heterocycles: The acridine series". Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 181 (junio de 2017): 286–308. http://dx.doi.org/10.1016/j.saa.2017.03.044.

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49

Gibadullina, E. M., E. A. Chugunova, E. V. Mironova, D. B. Krivolapov, A. R. Burilov, L. M. Yusupova y M. A. Pudovik. "Reaction of 4,6-Dichloro-5-nitrobenzofuroxan with aromatic amines and nitrogen-containing heterocycles". Chemistry of Heterocyclic Compounds 48, n.º 8 (noviembre de 2012): 1228–34. http://dx.doi.org/10.1007/s10593-012-1126-8.

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50

Nissinen, Maija y Kari Rissanen. "Crystal Engineering Studies of the Complexes of Ethyl Resorcinarene with Aromatic Nitrogen Heterocycles". Supramolecular Chemistry 15, n.º 7-8 (1 de octubre de 2003): 581–90. http://dx.doi.org/10.1080/10610270310001605179.

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