Thematische Bibliographien / Aromatic Nitrogen-heterocycles

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  1. Zeitschriftenartikel
  2. Dissertationen
  3. Buchteile
  4. Konferenzberichte

Auswahl der wissenschaftlichen Literatur zum Thema „Aromatic Nitrogen-heterocycles“

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Veröffentlicht am 18. Mai 2024

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Zeitschriftenartikel zum Thema "Aromatic Nitrogen-heterocycles"

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Zong, He-Hou, Chuang Yao, Chang Q. Sun, Jian-Guo Zhang und Lei Zhang. „Structure and Stability of Aromatic Nitrogen Heterocycles Used in the Field of Energetic Materials“. Molecules 25, Nr. 14 (15.07.2020): 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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Palumbo Piccionello, Antonio. „Editorial for Special Issue “Bioactive Oxadiazoles”“. International Journal of Molecular Sciences 22, Nr. 8 (13.04.2021): 3988. http://dx.doi.org/10.3390/ijms22083988.

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Palumbo Piccionello, Antonio. „Bioactive Oxadiazoles 2.0“. International Journal of Molecular Sciences 23, Nr. 7 (31.03.2022): 3841. http://dx.doi.org/10.3390/ijms23073841.

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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, Nr. 4 (2015): 1471–78. http://dx.doi.org/10.1039/c4nr05390g.

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Sachar, Anand, Poonam Gupta, Shallu Gupta und 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, Nr. 5 (Mai 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 (November 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 und 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, Nr. 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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McGuire, Brett A., Andrew M. Burkhardt, Sergei Kalenskii, Christopher N. Shingledecker, Anthony J. Remijan, Eric Herbst und Michael C. McCarthy. „Detection of the aromatic molecule benzonitrile (c-C6H5CN) in the interstellar medium“. Science 359, Nr. 6372 (11.01.2018): 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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He, Jiwen, Xingguo Zhang, Qiuqin He, Hao Guo und Renhua Fan. „Synthesis of 15N-labeled heterocycles via the cleavage of C–N bonds of anilines and glycine-15N“. Chemical Communications 57, Nr. 44 (2021): 5442–45. http://dx.doi.org/10.1039/d1cc01734a.

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Glišić, Biljana Đ., Ivana Aleksic, Peter Comba, Hubert Wadepohl, Tatjana Ilic-Tomic, Jasmina Nikodinovic-Runic und Miloš I. Djuran. „Copper(ii) complexes with aromatic nitrogen-containing heterocycles as effective inhibitors of quorum sensing activity in Pseudomonas aeruginosa“. RSC Advances 6, Nr. 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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Dissertationen zum Thema "Aromatic Nitrogen-heterocycles"

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Peng, Hao. „Investigations toward metal-free hydroamination approaches to aromatic nitrogen heterocycles“. Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28874.

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Metal-free hydroamination approaches were investigated to afford aromatic nitrogen heterocycles. Several substrates were synthesized to test different sequences such as 6-endo-dig and 6-exo-dig cyclization. The desired reactivity was observed for each of the desired routes, which were discussed in Chapter 2. More research is needed for optimization in the future.* *Please refer to dissertation for diagrams.
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Fulton, Craig Kennedy. „The microbial transformation of nitrogen and sulphur containing heterocycles fused to aromatic centres“. Thesis, University of Leicester, 2000. http://hdl.handle.net/2381/29649.

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The microbial degradation of isothiazolin rings was investigated. A mixed culture of bacteria able to utilise the isothiazolin ring containing compound saccharin as a source of carbon and nitrogen was isolated. A single type of bacterium able to utilise saccharin as a source of nitrogen was isolated from the community and identified as an Alcaligenes sp. A second organism able to utilise benzoate as a carbon source was isolated and identified as a Pseudomonas sp. Together the two bacteria were able to utilise saccharin as a source of carbon and nitrogen. The end products ammonia, sulphite, sulphate and catechol were detected during utilisation of saccharin by the Alcaligenes sp. When the Alcaligenes sp. and the Pseudomonas sp. grew in co-culture utilising saccharin as the carbon and nitrogen source the end products ammonia, sulphite and sulphate were detected. To investigate the cleavage of sulphur-nitrogen bonds sulphamate was used as a nitrogen source for the growth of bacteria. A single type of bacterium was isolated and identified as a Mycobacterium sp. A protein, termed sulphamate hydrolase, was isolated which was able to hydrolyse sulphamate to yield sulphate and ammonia. The protein had a sub-unit molecular mass of 50.8 kDa and a native molecular mass of 286 kDa. Based on this information the protein was presumed to be a hexamer composed of identical sub-units. A relatively high Km value of 26 mM and a low catalytic efficiency value of 413 M-1.s-1 was found which suggests that the enzyme is not ideally suited to the hydrolysis of sulphamate.
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Anand, R. „Synthesis of nitrogen containing heterocycles and acid catalyzed reactions of aromatic amines over medium and large pore zeolites“. Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2002. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2343.

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Yue, Congyong. „Palladium complexes of aromatic amide-derived phosphines and application for synthesis of biaryls, nitrogen heterocycles, and benzo[b]furans /“. View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202009%20YUE.

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Leone, Loredana. „Synthesis, properties and applications of bioinspired nitrogen and/or group 16 aromatic heterocycles“. Tesi di dottorato, 2014. http://www.fedoa.unina.it/9937/1/Leone_Loredana_26.pdf.

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A prominent position among naturally occurring N,S heterocyclic systems is occupied by 1,4-benzothiazines that form the key structural unit of pheomelanin pigments responsible for the red hair phenotype, typically found in red hair individuals with pale skin and enhanced susceptibility to skin cancer and melanoma. The chromophore exhibited by these pigments has been associated to the presence of the Δ2,2'-bi-(2H-1,4-benzothiazine) system. This is an indigo type chromophore which has not so far been fully exploited in the field of functional dyes. This Δ2,2'-bi-(2H-1,4-benzothiazine) exhibits a significant pH dependence, with a bathochromic shift from red to blue in acids and a marked photochromism under sunlight with reversible conversion in organic solvents of a yellow-orange species with abs max at 450 nm to a red one with abs max at 480 nm. Another related chromophore based on a push pull system occurs in the natural pigments cyanines, having organic nitrogen centers, one of the imine and the other of the enamine type. Some of these cyanines are currently used as biological reporters and in other technological applications . In this PhD project the research activity has been focused on 1,4-benzothiazine systems. Inspired by the peculiar properties of the chromophore exhibited by pheomelanin and natural cyanines the access to new classes of dyes with potential technological applications has been explored. The role of the benzothiazine structural units in the biological function of pheomelanin pigment was also addressed. Structural re-examination of the stable yellow isomer of 2,2’-bibenzothiazine by an integrated 2D NMR and theoretical approach revealed that the stable yellow species is in fact the cis isomer. A novel picture of 2,2’-bibenzothiazine as a four-state system with photochromic and pH-dependent behavior was proposed. Stable 3-substituted 1,4-benzothiazines, namely the 3-phenyl- and the 3-methyl-2H-1,4-benzothiazine were obtained by improvement of previously reported procedures in 50-60% average yields. When exposed to peroxides or biologically relevant metals at micromolar concentration and in the presence of strong acids, 3-phenyl-2H-1,4-benzothiazine is efficiently converted to a green-blue 2,2’-bi(2H-1,4-benzothiazine) via colorless intermediates identified as single-bonded dimers. A resonance-stabilized benzothiazinyl radical intermediate was evidenced and characterized by EPR spectroscopy. Interestingly, 3-phenyl-2H-1,4-benzothiazine proved useful for the visual detection of peroxides in aged ethereal solvents and an efficient inhibitor against corrosion of the rusty iron objects induced by concentrated HCl. Two different approaches were pursued for the synthetic access to benzothiazine cyanines, one involving reaction with dialdehydes that may allow for the build-up of a conjugated bridge between the two benzothiazine units and the other based on the condensation of the benzothiazine with aromatic para N-alkyl substituted aldehydes. All these products showed a marked pH dependence of the chromophores, associated in some cases to high molar extinction coefficients (up to 18,000), and emission of fluorescence tunable with the pH conditions. The chemistry of benzothiazine units accounting for the biological function of pheomelanin pigments was also addressed. Though commonly regarded as photosensitizer agents capable of amplifying generation of reactive oxygen species following UV radiation, recently, pheomelanin has also been implicated in UV-independent pathways of oxidative stress. To get an insight into these processes the reactivity of natural and synthetic pheomelanins toward critical cellular antioxidants was investigated. A marked ability of pheomelanin from red human hair, but not of eumelanin from black human hair to reduce the levels of GSH and NADH was evidenced. In the absence of oxygen GSH and NADH depletion was not observed while the presence of enzymes as superoxide dismutase and catalase did not modify the effect of pheomelanin suggesting a ROS independent mechanism. The mechanism of GSH oxidation by red hair pheomelanin was investigated by EPR spectroscopy. During a visit at the Department of Chemical Physics of Lund University (Sweden) in the research unit headed by professor Sundstrom, the photochemistry of putative structural subunits of pheomelanin including benzothiazoles, benzothiazine dimers and dihydroisoquinolines as well as of the natural pigments and synthetic models was investigated. Steady state absorption and emission spectra at different pHs showed marked differences that can be accounted for in terms of the ionization state of the functional groups. Time resolved measurements under different pH conditions allowed for identification of short lived species and characterization of fast processes like intramolecular and solvent proton transfer that are primary processes of excited state deactivation. Analysis of the results indicated the major role of the benzothiazine units compared to benzothiazole and 3-substituted units in determining the behaviour of natural pheomelanins.
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Krishnan, Anand. „Synthesis of Bioactive Nitrogen Heterocycles and Functionalized Nanomaterials for Biological and Catalytic Applications“. Thesis, 2015. http://hdl.handle.net/10321/1181.

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Submitted in fulfillment of the requirements of the Degree of Doctor of Technology: Chemistry,Durban University of Technology, 2014.
Aromatic heterocycles are highly important structural units found in a large number of biologically active natural compounds, pharmaceuticals and catalytic compounds. They have a crucial role in organic syntheses, which results in the generation of high value products. Among heterocycles, those containing nitrogen are the most indispensable structural motifs and are widely used against dreaded diseases such as Malaria, TB, HIV/AIDS and Cancer. The inclusion of highly electronegative atoms such as fluorine in these organic molecules render them very reactive towards proteins. Furthermore these molecules exhibit strong interactions with surfaces of quantum range particles of elemental gold. Various approaches for the synthesis of novel gold nanoparticles linked to potent bioactive molecules are documented and their application as drug delivery systems are of immense value to human health. Also many chemical and physical methods are available for the synthesis of gold, silver and palladium nanoparticles however these methods are usually laborious and produce toxic by-products. The green approach is to use plant extracts to synthesise various size and shape nanoparticles which could be used in biological and catalytic systems. A simple one-pot two component and three component reaction using formyl quinoline, 2-aminothiophenol, thiosemicarbazone and trifluoromethylbenzaldehyde as a reactant to synthesise quinoline, pyridine and pyran based bioactive small molecules; these products are a quinoline type bearing a benzothiazole moiety, quinoline thio semicarbazone ligand, fluorine substituted dihydro pyridine, fluorine substituted dihydropyran and fluorine substituted pyridine derivatives. In total, fifteen compounds were synthesized eleven of which were novel; all compounds were characterized by spectroscopic techniques. In vitro anti-bacterial activities of the synthesized compounds were investigated against a representative panel of pathogenic strains. Compounds 6, 7, 8, 11 and 13 exhibited excellent anti-bacterial activity compared with first line drugs. Potent p53–MDM2 interaction inhibitors 2-thio-1,2-dihydroquinoline-3-carbaldehyde thiosemicarbazone and fluorine substituted new pyridine scaffold were successfully identified by structure-based design. An efficient one-pot four component route to the synthesis of trifluorinated pyrrolophenanthroline and fluoroquinoline pyrrolophenanthrolines was designed. In this reaction 1-butyl-2,3-dimethylimidazolium tetrafluoroborate ionic liquid (DMTIL) was used as a reaction medium; no catalyst was required. The structure of the pyrrolophenanthrolines was deduced by IR and NMR analysis. These compounds were studied with Bovine Serum Albumin (BSA) through molecular docking. Hydrophopic, electrostatic and hydrogen bonding interaction played a crucial role in the binding to sub domain of BSA. Interaction studies of DMTIL with BSA by emission, absorption, synchronous fluorescence, circular dichroism (CD) and three dimensional emission (3D) spectroscopic techniques were under taken. The results from emission titration experiments revealed the existence of a strong interaction between BSA and DMTIL ionic liquid. It showed that compounds with lesser number of hydrogen bonds are found to be more active which is attributed to hydrophobic interaction and electrostatic interaction which also played a vital role in DMTIL binding to sub domain IB of BSA. A novel copper-loaded boron nitride nanosheet (Cu/BN) catalyst was prepared and fully characterized. It was used as an efficient and chemoselective catalysts for the synthesis of α-aminophosphonates by the Kabachnik-Fields reaction; twenty one α-aminophosphonates were synthesised. The enhanced catalytic activity and product yield was attributed to the increase of surface acidity. Overall, this methodology offered competitive advantages such as recyclability of the catalyst without further purification or without using additives or cofactors, low catalyst loading, broad substrate applicability and high yields. The application of this new nanocatalyst in organic synthesis will provide a novel pathway for the synthesis of pharmaceutically important compounds. Gold nanoparticle surfaces were modified with self-assembled monolayers of important thiol and disulfide bioactive molecules since considerable interest is due to their potential application as anti-cancer agents. Herein, a carbazole was conjugated to lipoic acid by using an amide coupling catalyst HBTU and DIEA reaction. The structure of the carbazole thio octanic acid (CTN) was identified by IR and NMR. CTN was attached to the gold nanoparticles surface and the capping behaviour was characterized by UV-vis spectroscopy, TEM, DLS and FTIR. The cytotoxicity of CTNAuNPs on A549 cell lines was determined using the MTT assay. The results suggest CTN and CTNAuNPs possess anti-proliferative properties in the cancerous A549 cells. Furthermore a dual thiol ligand was synthesized by using equimolar 4-aminothiophenol (4-ATP) and amino oxadiazole thiol (AXT). This dual ligand was attached to the gold nanoparticles surface (DTAu) and the capping behaviour was characterized by UV-vis spectroscopy, TEM, DLS and FTIR. The cytotoxicity of DTAu on A549 cell lines was determined using the MTT assay. The results suggest dual ligands (4-ATP, AXT) and DTAu possess anti-proliferative properties in the cancerous A549 cells. South African indigenous plants and agroforestry waste were also used in the synthesis of silver, gold and palladium nanoparticles (NPs). Green protocols such as the use of environmentally benign solvents and non-hazardous reagents were an added advantage to physical and chemical means. Furthermore these reactions were rapid and the size and shape of the NPs could be manipulated by choosing the correct medium. The formulation of natural medicinal compounds capped onto NPs was assessed for their anti-cancer activity, in A549 lung cancer line, and catalytic reduction of dyes and nitrobenzene derivatives were studied. These NPs displayed: Significant cytotoxicity to lung cancer cells with minimal effect on normal healthy cells. Outstanding catalytic reduction of pharmaceutical and textile waste effluents such as dyes and nitro aromatic compounds. In addition, palladium nanoparticles containing capped Moringa olifera compounds were used effectively in the Suzuki coupling reaction of iodobenzene and phenylboronic acid. The reaction was rapid and was conducted in an aqueous medium.
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Buchteile zum Thema "Aromatic Nitrogen-heterocycles"

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Clayden, Jonathan, Nick Greeves und Stuart Warren. „Aromatic heterocycles 1: reactions“. In Organic Chemistry. Oxford University Press, 2012. http://dx.doi.org/10.1093/hesc/9780199270293.003.0029.

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This chapter investigates the reactions of aromatic heterocycles. Benzene is aromatic because it has six electrons in a cyclic conjugated system. Most organic compounds belong to the class of aromatic heterocycles, and they number among them some of the most significant compounds for human beings. The chapter begins by considering how aromaticity survives when parts of benzene’s ring are replaced by nitrogen atoms. How can we insert a heteroatom into the ring and retain aromaticity? What kind of atom is needed? If we want to replace one of the carbon atoms of benzene with a heteroatom, we need an atom that can be trigonal to keep the flat hexagonal ring, and that has a p orbital to keep the six delocalized electrons. Nitrogen fits all of these requirements. This is what happens if we replace a CH group in benzene with a nitrogen atom. The chapter then looks at reactions of five-membered heterocycles, as well as benzo-fused heterocycles.
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Davies, David T. „Five-membered ring heterocycles with three or four heteroatoms“. In Aromatic Heterocyclic Chemistry. Oxford University Press, 1992. http://dx.doi.org/10.1093/hesc/9780198556602.003.0008.

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This chapter addresses the broad category of five-membered ring heterocycles containing three or four heteroatoms, which encompasses many heterocyclic systems. Obviously, there is considerable variation in the physical and chemical properties of such a large group of heterocycles. For instance, with regard to aromaticity, oxadiazole is considered to be less aromatic than triazole or tetrazole. Nevertheless, this collection of heterocycles does share certain characteristics. The trend of decreasing tendency towards electrophilic substitution on going from furan, pyrrole, and thiophene to the azoles is continued into these series. The presence of additional ‘pyridine-like’ nitrogen atoms renders these systems particularly ‘electron-deficient’, and electrophilic substitution is of little importance. Conversely, nucleophilic substitution does occur in these systems. The chapter then considers the synthesis of 1,2,4-ozadiazoles; 1,2,3-triazoles; and tetrazoles.
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Davies, David T. „Isoxazoles, pyrazoles, and isothiazoles“. In Aromatic Heterocyclic Chemistry. Oxford University Press, 1992. http://dx.doi.org/10.1093/hesc/9780198556602.003.0004.

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This chapter investigates isoxazoles, pyrazoles, and isothiazoles. Isoxazole, pyrazole, and isothiazole are the parent structures of the 1,2-azole family of heterocycles, having a nitrogen atom plus one other heteroatom in a 1,2-relationship in a five-membered ring. The aromatic sextet is completed by delocalization of the lone pair from the second heteroatom. Consequently, as in pyridine, the nitrogen atoms of the 1,2-azoles have a lone pair available for protonation. However, the 1,2-azoles are significantly less basic than the 1,3-azoles because of the electron-withdrawing effect of the adjacent heteroatom. Isoxazole and isothiazole are essentially non-basic heterocycles, and even pyrazole is a much weaker base than the corresponding 1,3-azole imidazole. As with substituted imidazoles, substituted pyrazoles may exist as a mixture of tautomers. The chapter then looks at the synthesis, electrophilic substitution, and anion chemistry of isoxazoles, pyrazoles, and isothiazoles.
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Byers, Jeffrey H., Gregory W. Woo, Anne J. Dewitt, Michael P. Duff und Christopher G. Nasveschuk. „Radical Aromatic Substitution on Nitrogen Heterocycles“. In 19th International Congress on Heterocyclic Chemistry, 127. Elsevier, 2003. http://dx.doi.org/10.1016/b978-0-08-044304-1.50119-2.

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Davies, David T. „Pyrimidines“. In Aromatic Heterocyclic Chemistry. Oxford University Press, 1992. http://dx.doi.org/10.1093/hesc/9780198556602.003.0010.

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This chapter explores pyrimidines. Formal replacement of a CH unit in pyridine by a nitrogen atom leads to the series of three possible diazines: pyridazine, pyrimidine, and pyrazine. Like pyridine, they are fully aromatic heterocycles. The effect of an additional nitrogen atom as compared to pyridine accentuates the essential features of pyridine chemistry. Electrophilic substitution is difficult in simple unactivated diazines because of both extensive protonation under strongly acidic conditions and the inherent lack of reactivity of the free base. Nucleophilic displacements are comparatively easier. The most important of the diazines is pyrimidine. The actual biosynthesis of purines involves construction of a pyrimidine ring onto a pre-formed imidazole. The chapter then considers the synthesis and chemistry of the pyrimidine ring system.
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Davies, G. H. M., und S. R. Wisniewski. „6.1.43 Product Subclass 43: Azaborines (Borazines)“. In Knowledge Updates 2021/2. Stuttgart: Georg Thieme Verlag KG, 2021. http://dx.doi.org/10.1055/sos-sd-106-00205.

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AbstractAzaborines (or borazines) represent an interesting class of heterocycles incorporating a boron–nitrogen structural motif within an aromatic ring system. This creates a system that is isosteric to traditional all-carbon ring systems, as the lone pair on nitrogen can donate into the empty orbital at boron to afford aromatic properties. Reviewed herein are synthetic strategies to access mono- and bicyclic azaborine cores, along with subsequent functionalization strategies, some of which are uniquely applicable due to the inherent dipole imparted on these ring systems.
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Davies, David T. „Quinolines and isoquinolines“. In Aromatic Heterocyclic Chemistry. Oxford University Press, 1992. http://dx.doi.org/10.1093/hesc/9780198556602.003.0006.

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This chapter assesses quinolines and isoquinolines. Quinoline and isoquinoline are two isomeric heterocyclic systems, which can be envisaged as being constructed from the fusion of a benzene ring at the C2/C3 and C3/C4 positions of pyridine respectively. They are both ten π-electron aromatic heterocycles. Like pyridine, they are moderately basic. Indeed, quinoline is sometimes used as a high boiling-point basic solvent. As with pyridine, the nitrogen atoms of quinoline and isoquinoline each bear a lone pair of electrons not involved in aromatic bonding which can be protonated, alkylated, or complexed to Lewis acids. The chapter then considers the synthesis, electrophilic substitution, nucleophilic substitution, and anion chemistry of quinoline and isoquinoline.
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Comins, Daniel L., und Sean O'Connor. „Regioselective Substitution in Aromatic Six-Membered Nitrogen Heterocycles“. In Advances in Heterocyclic Chemistry Volume 44, 199–267. Elsevier, 1988. http://dx.doi.org/10.1016/s0065-2725(08)60263-9.

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„Chapter 2 Reactivity of six-membered heterocycles“. In Exercise book on Aromatic Nitrogen Heterocycles Chemistry, 35–56. EDP Sciences, 2023. http://dx.doi.org/10.1051/978-2-7598-3082-4.c004.

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„Chapter 3 Reactivity of five-membered heterocycles“. In Exercise book on Aromatic Nitrogen Heterocycles Chemistry, 57–72. EDP Sciences, 2023. http://dx.doi.org/10.1051/978-2-7598-3082-4.c005.

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Konferenzberichte zum Thema "Aromatic Nitrogen-heterocycles"

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Andrejević, Tina P., Darko P. Ašanin, Nada D. Savić, Nevena Lj Stevanović, Miloš I. Djuran und Biljana Đ. Glišić. „DNA/BSA BINDING STUDY OF DINUCLEAR GOLD(III) COMPLEXES WITH AROMATIC NITROGEN-CONTAINING HETEROCYCLES AS BRIDGING LIGANDS“. In 1st INTERNATIONAL Conference on Chemo and BioInformatics. Institute for Information Technologies, University of Kragujevac, 2021. http://dx.doi.org/10.46793/iccbi21.312a.

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In recent decades, a special attention has been devoted to gold(III) complexes as potential antitumor agents due to their structural similarity to platinum(II) complexes. One of the possible mechanisms of the mode of antitumor activity of gold(III) complexes could include their interaction with DNA. However, the effectiveness of the therapeutic agents also depends on the degree of its binding to proteins present in the blood plasma, because, in this way, it is transported to the cell. Considering this, we investigated the interactions of three dinuclear gold(III) complexes of the general formula [{AuCl3}2(μ– L)], L = 4,4’-bipy (4,4’-bipyridine, Au1), bpe (1,2-bis(4-pyridyl)ethane, Au2) and dpe (1,2-bis(4- pyridyl)ethene, Au3) with calf thymus DNA (ct-DNA) and bovine serum albumin (BSA). The main aim of the study was to evaluate the binding affinities of gold(III) complexes Au1–3 towards these biomolecules for possible insights on their mode of biological activity. The values of binding constants (KA) of Au1–3 to ct-DNA are higher than those for BSA, indicating greater affinity of the complexes towards this nucleic acid. The partition coefficient (logP) value for Au1 is higher compared to the corresponding values for the other two complexes, what is in accordance with a higher cellular uptake efficiency of this complex.
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Stevanović, Nevena Lj, Mia Stanković, Tina P. Andrejević, Darko P. Ašanin, Ivana M. Stanojević und Biljana Đ. Glišić. „DNA AND BSA INTERACTIONS OF COPPER(II) AND ZINC(II) COMPLEXES WITH ANTIFUNGAL AGENT FLUCONAZOLE“. In 1st INTERNATIONAL Conference on Chemo and BioInformatics. Institute for Information Technologies, University of Kragujevac, 2021. http://dx.doi.org/10.46793/iccbi21.399s.

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Aromatic nitrogen-containing heterocycles (N-heterocycles) have attracted a considerable attention as scaffolds for compounds, which have an application in different pharmacological areas, ranging from vitamins to different antimicrobial and antitumor agents. In this respect, azoles are of special importance as potent and broad-spectrum agents used for the treatment of many invasive fungal infections. In the present study, the interaction of the clinically used antifungal drug fluconazole (fcz) and its copper(II) and zinc(II) complexes, {[CuCl2(fcz)2].5H2O}n (1) and {[ZnCl2(fcz)2]·2C2H5OH}n (2), with calf thymus DNA (ct- DNA) and bovine serum albumin (BSA) has been investigated. Fluorescence emission spectroscopy was applied for the binding study of complexes 1 and 2 and fcz with ct-DNA and BSA, while cyclic voltammetry was additionally used for investigation of their interactions with ct-DNA. The values of calculated binding constants (KA) of the investigated compounds towards ct-DNA and BSA follow the order fcz < 1 < 2 and 2 < fcz < 1, respectively.
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