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Journal articles on the topic 'Pyrene'

Author: Grafiati

Published: 4 June 2021

Last updated: 9 June 2025

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Babu, Srinivasarao Arulananda, and Arup Dalal. "Pd(II)-Catalyzed Directing-Group-Aided C–H Arylation and Alkylation of Pyrene Core: Synthesis of C1,C2- and C1,C10-Disubstituted Pyrene Motifs." Synthesis 53, no. 18 (March 31, 2021): 3307–24. http://dx.doi.org/10.1055/a-1472-0881.

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AbstractWe report the application of the Pd(II)-catalyzed, directing-group-aided C–H arylation/alkylation tactics to functionalize the pyrene core, especially, the relatively inaccessible C2 and K-region C10 positions of the pyrene core and augmentation of the library of pyrene derivatives with C1,C2- and C1,C10-disubstituted pyrene motifs. The Pd(II)-catalyzed β-C–H arylation/alkylation of the C2-position of pyrene-1-carboxamide possessing an 8-aminoquinoline directing group yielded various C1,C2-disubstituted pyrenes. Similarly, the Pd(II)-catalyzed selective γ-C–H arylation/alkylation of the C10-position of N-(pyren-1-yl)picolinamide, possessing a picolinamide directing group, yielded various C1,C10-disubstituted pyrenes. Examples of C(9)–H arylation of pyrene-1-carboxamide and the removal of the directing group after the C–H arylation/alkylation reactions were also shown. The structures of representative pyrene derivatives were confirmed by the X-ray structure analysis. Given the importance of the pyrene derivatives in various fields of chemical sciences, this report is a contribution towards augmentation of the library of pyrene derivatives with C1,C2- and C1,C10-disubstituted pyrene amide motifs.

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TAKEDA, FUMIOMI. "CHARACTERIZATION OF BLACKBERRY PYRENES." HortScience 28, no. 5 (May 1993): 488e—488. http://dx.doi.org/10.21273/hortsci.28.5.488e.

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Pyrene (the pit of a druplet) size is a factor contributing to blackberry fruit quality. Large pyrene size, based on weight, length, or volume, and “seediness” is undesirable in processed blackberry products. Several of the recently released eastern thornless and erect Arkansas blackberries can be alternative sources of quality fruits for processors. The purpose of this study was to compare pyrenes of blackberries from the Oregon (O), Arkansas (A), and eastern USDA (E) breeding programs. Pyrene size (length) ranged from 2.5 mm in `Darrow' to 4.0 mm in `Black Satin' and `Merton Tnornless'. Pyrenes of A blackberries generally were ellipsoidal and smaller than E blackberries which were “clam” shaped. Pyrenes of E blackberries such as `Black Satin' and `Chester' had a thick endocarp and were much thicker and wider than A and O blackberries. In contrast, several O blackberries including 'Marion' had flat pyrenes with a soft, thin endocarp. The results of this study indicate that the pyrene thickness trait is a major factor contributing to seediness.

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Arulananda Babu, Srinivasarao, Arup Dalal, and Subhankar Bodak. "Recent Advances in C–H Functionalization of Pyrenes." Chemistry 5, no. 4 (December 11, 2023): 2713–55. http://dx.doi.org/10.3390/chemistry5040175.

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In recent years, transition metal-catalyzed C–H activation and site-selective functionalization have been considered to be valuable synthetic tactics to functionalize organic compounds containing multiple C–H bonds. Pyrene is one of the privileged and notorious polycyclic aromatic hydrocarbons. Pyrene and its derivatives have found applications in various branches of chemical sciences, including organic chemistry, chemical biology, supramolecular sciences, and material sciences. Given the importance of pyrene derivatives, several classical methods, including the C–H functionalization method, have been developed for synthesizing modified pyrene scaffolds. This review attempts to cover the recent developments in the area pertaining to the modification of the pyrene motif through the C–H activation process and the functionalization of C–H bonds present in the pyrene motif, leading to functionalized pyrenes.

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Ashley, David L., Elizabeth R. Barnhart, Donald G. Patterson, and Robert H. Hill. "Identification of Polychlorinated Pyrenes and Pyrene-Addition Products Using Proton Nuclear Magnetic Resonance Techniques." Applied Spectroscopy 41, no. 7 (September 1987): 1194–99. http://dx.doi.org/10.1366/0003702874447428.

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Nuclear magnetic resonance (NMR) techniques are used to determine the chlorination pattern on a number of chlorinated pyrenes and pyrene-addition products. Determining chemical shifts, couplings, and longitudinal relaxation rates makes the unequivocal assignment of these molecules possible. Chlorination under the conditions described here were found to follow the normal orientation rules for pyrene. Spectral parameters obtained from these molecules are consistent enough to allow further application to unknown compounds. This should simplify assigning NMR spectra to other chlorinated pyrene standards.

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Orehovec, Iva, Marija Matković, Isabela Pehar, Dragomira Majhen, and Ivo Piantanida. "Bis-Pyrene Photo-Switch Open- and Closed-Form Differently Bind to ds-DNA, ds-RNA and Serum Albumin and Reveal Light-Induced Bioactivity." International Journal of Molecular Sciences 22, no. 9 (May 6, 2021): 4916. http://dx.doi.org/10.3390/ijms22094916.

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Newly designed and synthesized diarylethene (DAE) derivatives with aliphatic amine sidearms and one with two pyrenes, revealed excellent photo-switching property of central DAE core in MeOH and water. The only exception was bis-pyrene analogue, its DAE core very readily photochemically closed, but reversible opening completely hampered by aromatic stacking interaction of pyrene(s) with cyclic DAE. In this process, pyrene fluorescence showed to be a reliable monitoring method, an open form characterized by strong emission at 480 nm (typical for pyrene-aggregate), while closed form emitted weakly at 400 nm (typical for pyrene-DAE quenching). Only open DAE-bis-pyrene form interacted measurably with ds-DNA/RNA by flexible insertion in polynucleotide grooves, while self-stacked closed form did not bind to DNA/RNA. For the same steric reasons, flexible open DAE-bis-pyrene form was bound to at least three different binding sites at bovine serum albumin (BSA), while rigid, self-stacked closed form interacted dominantly with only one BSA site. Preliminary screening of antiproliferative activity against human lung carcinoma cell line A549 revealed that all DAE-derivatives are non-toxic. However, bis-pyrene analogue efficiently entered cells and located in the cytoplasm, whereby irradiation by light (315–400 nm) resulted in a strong, photo-induced cytotoxic effect, typical for pyrene-related singlet oxygen species production.

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Babu, B. Ravindra, Mads D. Sørensen, Patrick J. Hrdlicka, Smriti Trikha, Ashok K. Prasad, Virinder S. Parmar, and Jesper Wengel. "Novel nucleic acid architectures involving locked nucleic acid (LNA) and pyrene residues: Results from an Indo-Danish collaboration." Pure and Applied Chemistry 77, no. 1 (January 1, 2005): 319–26. http://dx.doi.org/10.1351/pac200577010319.

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We report herein our results for locked nucleic acid (LNA)-type oligonucleotides containing pyrene residues. Pyrene has a large hydrophobic and planar surface area and is therefore a potential intercalating unit; furthermore, it is interesting as a fluorescent tag when covalently bound to DNA. Synthesis and hybridization of conformationally locked universal base surrogates are described together with efficient interstrand communication as shown by the formation of pyrene excimer bands for duplexes containing 2'-N-(pyren-1-yl)methyl-2'-amino-LNA monomers positioned in a zipper-like manner within a DNA duplex.

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Jasiura, Adam, Mateusz Gorzel, Konrad Warchoł, Wiktoria Lipczyńska, Wiktoria Lipczyńska, and Wiktoria Lipczyńska. "Benzo(a)pyrene - an air pollutant harmful to health in European countries." Medical Science Pulse 17, no. 3 (October 23, 2023): 1–7. http://dx.doi.org/10.5604/01.3001.0053.9255.

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Background: Benzo(a)pyrenes are organic compounds from the polycyclic aromatic hydrocarbons group known for their carcinogenic properties. Benzo(a)pyrenes are formed as a result of incomplete combustion of organic matter, such as biomass or fossil fuel.Aim of the study: To investigate whether respiratory diseases and malignant neoplasm-related deaths correlate to air concentrations of benzo(a)pyrene in European countries.Material and methods: Publicly available data were obtained regarding benzo(a)pyrene concentration from the EUROSTAT database, as well as territorial division in accordance with NUTS 2. Diseases were defined according to ICD-10.Results: There is a positive correlation of medium effect (r = 0.442; p < 0.001) between the annual average concentration of benzo(a)pyrene and deaths due to malignant neoplasms, with the strongest correlation being malignant bladder neoplasms (r = 0.502; p < 0.001). There is a positive correlation of a moderately weak effect (r = 0.221; p = 0.002) between the annual average concentration of benzo(a)pyrene and deaths due to respiratory diseases, with the strongest correlation for pneumonia of various etiologies, which is a positive correlation of a medium effect (r = 0.496; p < 0.001). Linear regression models showed that reducing the concentration of benzo(a)pyrene by 1 ng/m3 will reduce the frequency of deaths due to malignant laryngeal neoplasms by 0.816 per 1000 residents, malignant bladder neoplasms by 1.41 per 1000 residents, and deaths due to pneumonia by 11.26 per 1000 residents.Conclusions: We have found that benzo(a)pyrene concentration has a moderate correlation with death due to respiratory diseases and malignant neoplasms. More in-depth studies regarding other factors, e.g. the age of the patient are needed.

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Mimura, Yuki, Tomoki Nishikawa, Ryo Fuchino, Shiho Nakai, Nobuo Tajima, Mizuki Kitamatsu, Michiya Fujiki, and Yoshitane Imai. "Circularly polarised luminescence of pyrenyl di- and tri-peptides with mixed d- and l-amino acid residues." Organic & Biomolecular Chemistry 15, no. 21 (2017): 4548–53. http://dx.doi.org/10.1039/c7ob00503b.

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Silva, Beatriz E. Ruiz, Edward K. Koepf, Leslie D. Burtnick, and Nicholas J. Turro. "Monomer and excimer fluorescence of horse plasma gelsolin labelled with N-(1-pyrenyl)iodoacetamide." Biochemistry and Cell Biology 70, no. 7 (July 1, 1992): 573–78. http://dx.doi.org/10.1139/o92-088.

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Horse plasma gelsolin was labelled with the sulfhydryl-specific fluorescent reagent N-(1-pyrenyl)iodoacetamide. The level of incorporation of probe was 1.6 ± 0.3 mol pyrene/mol gelsolin. The circular dichroism spectrum of pyrenyl-gelsolin and its ability to interact with muscle actin were not different from that found for unmodified gelsolin. The emission from pyrenyl-gelsolin was dominated by a broad emission band centred near 483 nm, characteristic of the presence of pyrene excimers. Analysis of excitation spectra for the monomer and excimer-type fluorescence suggested that ground-state interactions may occur between adjacent pyrenes in the gelsolin structure. In the case either of excimer formation or of ground-state pyrene–pyrene interactions in doubly labelled gelsolin molecules, the modified Cys residues must be in close proximity in the folded protein structure. Thermal denaturation of gelsolin could be monitored by observing the decrease in excimer emission that accompanied heating and unfolding of the tertiary structure. While heat treatment alone did not eliminate excimer fluorescence, digestion of gelsolin with chymotrypsin completely abolished such emission. Also, pyrenyl-gelsolin prepared and studied in 6 M guanidine-HCl exhibited fluorescence characteristic of pyrene monomers exclusively.Key words: gelsolin, pyrene excimer fluorescence, fluorescence lifetime, thermal denaturation.

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Ruiu, Andrea, Mireille Vonlanthen, Sandra M. Rojas-Montoya, Israel González-Méndez, and Ernesto Rivera. "Unusual Fluorescence Behavior of Pyrene-Amine Containing Dendrimers." Molecules 24, no. 22 (November 12, 2019): 4083. http://dx.doi.org/10.3390/molecules24224083.

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A new class of pyrene-based dendrimers, characterized by the presence of a 1,4,7,10-Tetraazacyclododecane (cyclen) unit as the core, was studied by SSF (steady-state fluorescence) and SPC (single-photon counting fluorescence). The photophysical behavior of these dendrimers was studied in THF, DMF and DMSO solution. The typical signals for pyrene-labeled molecules were recorded in each solvent, showing the representative fluorescence spectra: the corresponding emissions of monomer and excimer of the pyrene chromophore are observed. Unexpectedly, the typical quenching of tertiary amine on the pyrene emission was not observed in these dendrimers. Quenching studies were performed by adding up to 3 equivalents of trifluoroacetic acid (TFA). To our knowledge, this is the first report of pyrene’s unquenching behavior by a tertiary amine.

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de Robillard, Guillaume, Oumayma Makni, Hélène Cattey, Jacques Andrieu, and Charles H. Devillers. "Towards sustainable synthesis of pyren-1-yl azoliums via electrochemical oxidative C–N coupling." Green Chemistry 17, no. 9 (2015): 4669–79. http://dx.doi.org/10.1039/c5gc01142f.

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Hill, Jonathan P., Katsuhiko Ariga, Amy Lea Schumacher, Paul A. Karr, and Francis D'Souza. "Pyren-1-ylmethyl N-substituted oxoporphyrinogens." Journal of Porphyrins and Phthalocyanines 11, no. 05 (May 2007): 390–96. http://dx.doi.org/10.1142/s1088424607000448.

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5,10,15,20-tetrakis(3,5-di-tert-butyl-4-oxocyclohexadien-2,5-yl)porphyrinogen was alkylated at its macrocyclic nitrogen atoms with pyren-1-ylmethyl groups and the effect of increasing N-substitution on the spectroscopic and electrochemical properties was investigated. Both pyrene and oxoporphyrinogen chromophores exhibit fluorescence and there is little interaction between them except in the higher N-substituted compounds. Intra- or intermolecular excimer formation by pyrene is precluded by attachment to the bulky oxoporphyrinogen. Electrochemical measurements revealed reversible redox behavior.

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Huang, Hong-Jui, Sonai Seenithurai, and Jeng-Da Chai. "TAO-DFT Study on the Electronic Properties of Diamond-Shaped Graphene Nanoflakes." Nanomaterials 10, no. 6 (June 25, 2020): 1236. http://dx.doi.org/10.3390/nano10061236.

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At the nanoscale, it has been rather troublesome to properly explore the properties associated with electronic systems exhibiting a radical nature using traditional electronic structure methods. Graphene nanoflakes, which are graphene nanostructures of different shapes and sizes, are typical examples. Recently, TAO-DFT (i.e., thermally-assisted-occupation density functional theory) has been formulated to tackle such challenging problems. As a result, we adopt TAO-DFT to explore the electronic properties associated with diamond-shaped graphene nanoflakes with n = 2–15 benzenoid rings fused together at each side, designated as n-pyrenes (as they could be expanded from pyrene). For all the n values considered, n-pyrenes are ground-state singlets. With increasing the size of n-pyrene, the singlet-triplet energy gap, vertical ionization potential, and fundamental gap monotonically decrease, while the vertical electron affinity and symmetrized von Neumann entropy (which is a quantitative measure of radical nature) monotonically increase. When n increases, there is a smooth transition from the nonradical character of the smaller n-pyrenes to the increasing polyradical nature of the larger n-pyrenes. Furthermore, the latter is shown to be related to the increasing concentration of active orbitals on the zigzag edges of the larger n-pyrenes.

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Kim, Hyunji, A.-Rong Kim, and Jong S. Park. "Synthesis and Property of Pyrene-Naphthalene Diimide-Pyrene Triad." Textile Coloration and Finishing 26, no. 4 (December 27, 2014): 305–10. http://dx.doi.org/10.5764/tcf.2014.26.4.305.

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Yamaji, Minoru, Hajime Maeda, Yasuaki Nanai, and Kazuhiko Mizuno. "Substitution Effects of C-C Triple Bonds on Deactivation Processes from the Fluorescent State of Pyrene Studied by Emission and Transient Absorption Measurements." ISRN Physical Chemistry 2012 (October 14, 2012): 1–7. http://dx.doi.org/10.5402/2012/103817.

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Pyrenes substituted with tert-butylethynyl, trimethylsilylethynyl, and trimethylsilylbutadiynyl groups were prepared, and the fluorescence yields (Φf), lifetimes, and triplet-triplet absorption were measured in cyclohexane. Upon introduction of the groups possessing triple bond(s) to the pyrene skeleton, the fluorescence rate (kf) increased. The variation of the terminating groups did not appreciably affect the Φf and kf values. Increasing the number of the triple bond, the kf values increased by the magnitude of order whereas the Φf were not varied. The effect of the ethynyl groups on the kf values was rationalized by the Strickler-Berg equation considering an increase of the 1La transition moment. Triplet-triplet absorption spectra of pyrene derivatives were obtained. The intersystem crossing rates (kisc) increased upon increasing the number of triple bonds terminated with the trimethylsilyl group whereas those between ethynylpyrenes were independent of the terminating groups. Heavy atom effect failed to rationalize the enhancement of the kisc values upon adding the triple bond to the pyrene moiety.

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Herbstein, Frank H. "Correction of the space group of [Ni(bipy)2(ONO2)2]·2(pyrene)." Acta Crystallographica Section B Structural Science 57, no. 4 (July 24, 2001): 517–19. http://dx.doi.org/10.1107/s0108768101007807.

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The crystal structure of [Ni(bipy)2(ONO2)2]·2(pyrene), poly[[[bis(nitrato-O)nickel(II)]bis(μ-4,4′-bipyridyl-N,N′] bis(pyrene)], was originally reported in space group Pn [Biradha et al. (1999). Chem. Commun. pp. 1327–1328]. Reasons are given for changing the space group to P21/n. Consequently, incorrect descriptions of the title compound in the literature must be altered. In particular, the structure is not polar. It is further contended that description in terms of `complementary, interpenetrating covalent and noncovalent two-dimensional networks' is misleading as the `noncovalent network' (of pyrenes) has geometrical but not physical significance. The title compound is a typical host–guest inclusion complex.

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Jiang, Chuang, Ling-Ling Li, and Xiao-Qi Yu. "A pyrene-based fast-responsive fluorescent probe for G-quadruplexes." Analytical Methods 9, no. 16 (2017): 2397–400. http://dx.doi.org/10.1039/c7ay00556c.

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A novel pyrene-based fluorescent probe (3-methyl-2-(pyren-1-yl)benzo[d]thiazol-3-ium iodide) (PBT) was found to be a fast-responsive and highly selective towards G-quadruplexes. PBT exhibited an opposite fluorescent variation tendency on binding with G-quadruplexes and ds-DNAs.

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Purvia, Anita Singh, and Vinoy Kumar Shrivastava. "Impact of Benzo (a) Pyrene on Thyroid Glands and their Associated Hormones of Male Mice Mus musculus." Asian Journal of Biochemistry, Genetics and Molecular Biology 16, no. 5 (April 3, 2024): 31–39. http://dx.doi.org/10.9734/ajbgmb/2024/v16i5375.

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Benzo [a] pyrene is the main representative of polycyclic aromatic hydrocarbons, and has been repeatedly found in the air, surface water, soil, and sediments. Human exposure to Benzo [a] pyrene is therefore common. Benzo (a) pyrane (BaP) which is mainly presented in newspaper ink and inhibits the function of the thyroid and other endocrine glands of the human system, due to several disorders that occur in the human body. Healthy mature male mice Mus musculus having weight of 125 ± 5 gm were used for the experiments. The effects of a Benzo (a) pyrene (0.65mg/25g body weight/twice in a week) during experimental periods of 60 and 90 days in male mice Mus musculus showed significant difference in body weights compared to control. We assessed the hormonal estimation of thyroid treated with Benzo (a) pyrene by using an appropriate ELISA assay kit and histopathological changes were observed under a light microscope (magnifications 100X) in the thyroid tissue of male mice Mus musculus exposed to BaP after 60 and 90 days. During the study, we observed that in treated mice thyroid hormone concertation was affected the structure of the thyroid follicles was disturbed and epithelial cells were necrotic compared with the control mice which indicates that the BaP may lead to changes in the thyroid morphology as well as secreted hormone concentration in exposed treated male mice.

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Liao, Junqiu, Shenglan Liu, Yongjie Yuan, and Hailiang Zhang. "Steric hindrance effect on the thermo- and photo-responsive properties of pyrene-based polymers." New Journal of Chemistry 42, no. 8 (2018): 5698–708. http://dx.doi.org/10.1039/c8nj00136g.

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We synthesized a novel series of pyrene-based thermo- and photo-dual responsive polymers named poly(pyren-1-yl-o(m,p)-vinylbenzoate) (P(Py-o(m,p)-VB)). And the influence of the steric hindrance effect on LCST-type phase behaviors and photocleavage properties has been studied.

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Zych, Dawid, and Aneta Slodek. "The Impact of a 1,2,3-Triazole Motif on the Photophysical Behavior of Non-K Tetrasubstituted Pyrene with a Substitution Pattern Providing the Long Axial Symmetry." Molecules 27, no. 13 (July 5, 2022): 4314. http://dx.doi.org/10.3390/molecules27134314.

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1,3,6,8-Tetrasubstituted pyrene derivatives with two types of substituents (4-(2,2-dimethylpropyloxy)pyridine, 1-decyl-1,2,3-triazole, 1-benzyl-1,2,3-triazole, and pyrazole), substituted in such a way that provides the long axial symmetry, are prepared and characterized in the present study. To the best of our knowledge, the pyrene derivative containing the same heteroaryl motif (triazole) but substituted by two various alkyls, straight decyl and benzyl-based side chains (C), is reported for the first time. For comparison, compounds with one kind of triazole motif and substituted pyridine or pyrazole groups were prepared (A and B). The photophysical properties of all molecules were evaluated by thermogravimetric analysis (TGA) and UV-Vis spectroscopy (absorption and emission spectra, quantum yields, and fluorescence lifetimes). The obtained results were compared to analogues substituted at the 1,3,6,8 positions by one kind of substituent and also with all the 1,3,6,8-tetrasubstituted pyrenes reported in the literature substituted by two kinds of substituents with a substitution pattern that provides long axial symmetry. In addition, theoretical studies based on DFT and TD-DFT were performed that supported the interpretation of the experimental results. The photophysical properties of tetrasubstituted pyrene derivatives having triazole units at the 1,8-positions, respectively, and other identical substituents at the 3,6 positions show the dominance of triazole units in the pyrene framework; the dominance is even higher in the case of the substitution of 1,3,6,8 positions by triazoles, but containing two various alkyls.

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Liang, Yanna, Dale R. Gardner, Charles D. Miller, Dong Chen, Anne J. Anderson, Bart C. Weimer, and Ronald C. Sims. "Study of Biochemical Pathways and Enzymes Involved in Pyrene Degradation by Mycobacterium sp. Strain KMS." Applied and Environmental Microbiology 72, no. 12 (October 13, 2006): 7821–28. http://dx.doi.org/10.1128/aem.01274-06.

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ABSTRACT Pyrene degradation is known in bacteria. In this study, Mycobacterium sp. strain KMS was used to study the metabolites produced during, and enzymes involved in, pyrene degradation. Several key metabolites, including pyrene-4,5-dione, cis-4,5-pyrene-dihydrodiol, phenanthrene-4,5-dicarboxylic acid, and 4-phenanthroic acid, were identified during pyrene degradation. Pyrene-4,5-dione, which accumulates as an end product in some gram-negative bacterial cultures, was further utilized and degraded by Mycobacterium sp. strain KMS. Enzymes involved in pyrene degradation by Mycobacterium sp. strain KMS were studied, using 2-D gel electrophoresis. The first protein in the catabolic pathway, aromatic-ring-hydroxylating dioxygenase, which oxidizes pyrene to cis-4,5-pyrene-dihydrodiol, was induced with the addition of pyrene and pyrene-4,5-dione to the cultures. The subcomponents of dioxygenase, including the alpha and beta subunits, 4Fe-4S ferredoxin, and the Rieske (2Fe-2S) region, were all induced. Other proteins responsible for further pyrene degradation, such as dihydrodiol dehydrogenase, oxidoreductase, and epoxide hydrolase, were also found to be significantly induced by the presence of pyrene and pyrene-4,5-dione. Several nonpathway-related proteins, including sterol-binding protein and cytochrome P450, were induced. A pyrene degradation pathway for Mycobacterium sp. strain KMS was proposed and confirmed by proteomic study by identifying almost all the enzymes required during the initial steps of pyrene degradation.

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Vila, Joaquim, and Magdalena Grifoll. "Actions of Mycobacterium sp. Strain AP1 on the Saturated- and Aromatic-Hydrocarbon Fractions of Fuel Oil in a Marine Medium." Applied and Environmental Microbiology 75, no. 19 (August 7, 2009): 6232–39. http://dx.doi.org/10.1128/aem.02726-08.

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ABSTRACT The pyrene-degrading Mycobacterium sp. strain AP1 grew in nutrient-supplemented artificial seawater with a heavy fuel oil as the sole carbon source, causing the complete removal of all linear (C12 to C40) and branched alkanes from the aliphatic fraction, as well as an extensive degradation of the three- and four-ring polycyclic aromatic hydrocarbons (PAHs) phenanthrene (95%), anthracene (80%), fluoranthene (80%), pyrene (75%), and benzo(a)anthracene (30%). Alkylated PAHs, which are more abundant in crude oils than the nonsubstituted compounds, were selectively attacked at extents that varied from more than 90% for dimethylnaphthalenes, methylphenanthrenes, methylfluorenes, and methyldibenzothiophenes to about 30% for monomethylated fluoranthenes/pyrenes and trimethylated phenanthrenes and dibenzothiophenes. Identification of key metabolites indicated the utilization of phenanthrene, pyrene, and fluoranthene by known assimilatory metabolic routes, while other components were cooxidized. Detection of mono- and dimethylated phthalic acids demonstrated ring cleavage and further oxidation of alkyl PAHs. The extensive degradation of the alkanes, the two-, three-, and four-ring PAHs, and their 1-, 2-, and 3-methyl derivatives from a complex mixture of hydrocarbons by Mycobacterium sp. strain AP1 illustrates the great substrate versatility of alkane- and PAH-degrading mycobacteria.

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Heo, Yeongjae, Hyukmin Kwon, Sangwook Park, Sunwoo Dae, Hayoon Lee, Kiho Lee, and Jongwook Park. "A High-Efficiency Deep Blue Emitter for OLEDs with a New Dual-Core Structure Incorporating ETL Characteristics." Molecules 28, no. 22 (November 8, 2023): 7485. http://dx.doi.org/10.3390/molecules28227485.

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In this study, we introduced the weak electron-accepting oxazole derivative 4,5-diphenyl-2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)oxazole (TPO) into both anthracene and pyrene moieties of a dual core structure. Ultimately, we developed 2-(4-(6-(anthracen-9-yl)pyren-1-yl)phenyl)-4,5-diphenyloxazole (AP-TPO) as the substitution on the second core, pyrene, and 4,5-diphenyl-2-(4-(10-(pyren-1-yl)anthracen-9-yl)phenyl)oxazole (TPO-AP) as the substitution on the first core, anthracene. Both materials exhibited maximum photoluminescence wavelengths at 433 and 443 nm in solution and emitted deep blue light with high photoluminescence quantum yields of 82% and 88%, respectively. When used as the emitting layer in non-doped devices, TPO-AP outperformed AP-TPO, achieving a current efficiency of 5.49 cd/A and an external quantum efficiency of 4.26% in electroluminescence. These materials introduce a new category of deep blue emitters in the organic light-emitting diodes field, combining characteristics related to the electron transport layer.

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Zych, Dawid. "1,3-Di(hetero)aryl-7-substituted Pyrenes—An Undiscovered Area of Important Pyrene Derivatives." Proceedings 41, no. 1 (November 14, 2019): 28. http://dx.doi.org/10.3390/ecsoc-23-06470.

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In this work, the necessity of synthesis of 1,3-di(hetero)aryl-7-substituted pyrenes is presented based on the results of theoretical calculations by using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) by using Gaussian 09 program with B3LYP exchange-correlation functional and 6-31G** basis set. What is more, the synthetic routes with feasible reagents and conditions are presented. The subject of theoretical considerations are two pyrene derivatives which contain at position 1 and 3 pyrazolyl substituents and at position 7 amine (1) or boron (2) derivative. The theoretical calculations were also performed for the osmium complexes with mentioned ligands (3 and 4). The influence of electron-donating/accepting character of the substituent at position 7 of pyrene on the properties of molecules has been established.

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Rubiyatno, Zee Chuang Teh, Diah Velentina Lestari, Arma Yulisa, Muthah Musa, Tse-Wei Chen, Noura M. Darwish, Bandar M. AlMunqedhi, and Tony Hadibarata. "Tolerance of earthworms in soil contaminated with polycyclic aromatic hydrocarbon." Industrial and Domestic Waste Management 2, no. 1 (April 5, 2022): 9–16. http://dx.doi.org/10.53623/idwm.v2i1.62.

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Pyrene is a very resistant polycyclic aromatic hydrocarbon (PAH) with four benzene rings that survives in the environment. This study was aimed at investigating the tolerance of earthworms in soil contaminated with pyrene. The studies were performed by employing earthworms gathered from shady regions adjacent to sewage ponds as pyrene degraders to eradicate pyrene from the soil. Numerous factors affecting pyrene degradation efficiency were explored, including the effects of contaminant concentration, earthworm and soil ration, and soil condition. The highest pyrene removal (31.2%) was shown by earthworms in the condition of soil mixed with cow dung. Pyrene decomposition was inhibited during soil sterilization due to the absence of soil microorganisms and indigenous pyrene-degrading bacteria. Nonetheless, earthworms are suitable for use as pyrene degraders in contaminated soil.

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Moody, Joanna D., James P. Freeman, Peter P. Fu, and Carl E. Cerniglia. "Degradation of Benzo[a]pyrene by Mycobacterium vanbaalenii PYR-1." Applied and Environmental Microbiology 70, no. 1 (January 2004): 340–45. http://dx.doi.org/10.1128/aem.70.1.340-345.2004.

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ABSTRACT Metabolism of the environmental pollutant benzo[a]pyrene in the bacterium Mycobacterium vanbaalenii PYR-1 was examined. This organism initially oxidized benzo[a]pyrene with dioxygenases and monooxygenases at C-4,5, C-9,10, and C-11,12. The metabolites were separated by reversed-phase high-performance liquid chromatography (HPLC) and characterized by UV-visible, mass, nuclear magnetic resonance, and circular dichroism spectral analyses. The major intermediates of benzo[a]pyrene metabolism that had accumulated in the culture media after 96 h of incubation were cis-4,5-dihydro-4,5-dihydroxybenzo[a]pyrene (benzo[a]pyrene cis-4,5-dihydrodiol), cis-11,12-dihydro-11,12-dihydroxybenzo[a]pyrene (benzo[a]pyrene cis-11,12-dihydrodiol), trans-11,12-dihydro-11,12-dihydroxybenzo[a]pyrene (benzo[a]pyrene trans-11,12-dihydrodiol), 10-oxabenzo[def]chrysen-9-one, and hydroxymethoxy and dimethoxy derivatives of benzo[a]pyrene. The ortho-ring fission products 4-formylchrysene-5-carboxylic acid and 4,5-chrysene-dicarboxylic acid and a monocarboxylated chrysene product were formed when replacement culture experiments were conducted with benzo[a]pyrene cis-4,5-dihydrodiol. Chiral stationary-phase HPLC analysis of the dihydrodiols indicated that benzo[a]pyrene cis-4,5-dihydrodiol had 30% 4S,5R and 70% 4R,5S absolute stereochemistry. Benzo[a]pyrene cis-11,12-dihydrodiol adopted an 11S,12R conformation with 100% optical purity. The enantiomeric composition of benzo[a]pyrene trans-11,12-dihydrodiol was an equal mixture of 11S,12S and 11R,12R molecules. The results of this study, in conjunction with those of previously reported studies, extend the pathways proposed for the bacterial metabolism of benzo[a]pyrene. Our study also provides evidence of the stereo- and regioselectivity of the oxygenases that catalyze the metabolism of benzo[a]pyrene in M. vanbaalenii PYR-1.

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Košćak, Marta, Isabela Pehar, Ksenija Božinović, Goutam Kumar Kole, Sandra Sobočanec, Iva I. Podgorski, Marija Pinterić, et al. "Para-N-Methylpyridinium Pyrenes: Impact of Positive Charge on ds-DNA/RNA and Protein Recognition, Photo-Induced Bioactivity, and Intracellular Localisation." Pharmaceutics 14, no. 11 (November 17, 2022): 2499. http://dx.doi.org/10.3390/pharmaceutics14112499.

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The 2- and 2,7- substituted para-N-methylpyridinium pyrene cations show high-affinity intercalation into ds-DNAs, whereas their non-methylated analogues interacted with ds-DNA/RNA only in the protonated form (at pH 5), but not at physiological conditions (pH 7). The fluorescence from non-methylated analogues was strongly dependent on the protonation of the pyridines; consequently, they act as fluorescence ratiometric probes for simultaneous detection of both ds-DNA and BSA at pH 5, relying on the ratio between intensities at 420 nm (BSA specific) and 520 nm (DNA specific), whereby exclusively ds-DNA sensing could be switched-off by adjustment to pH 7. Only methylated, permanently charged pyrenes show photoinduced cleavage of circular DNA, attributed to pyrene-mediated irradiation-induced production of singlet oxygen. Consequently, the moderate toxicity of these cations against human cell lines is strongly increased upon irradiation. Detailed studies revealed increased total ROS production in cells treated by the compounds studied, accompanied by cell swelling and augmentation of cellular complexity. The most photo-active 2-para-N-methylpyridinium pyrene showed significant localization at mitochondria, its photo-bioactivity likely due to mitochondrial DNA damage. Other derivatives were mostly non-selectively distributed between various cytoplasmic organelles, thus being less photoactive.

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Hu, Jie, Dong Zhang, and Frank W. Harris. "Ruthenium(III) Chloride Catalyzed Oxidation of Pyrene and 2,7-Disubstitued Pyrenes: An Efficient, One-Step Synthesis of Pyrene-4,5-diones and Pyrene-4,5,9,10-tetraones." Journal of Organic Chemistry 70, no. 2 (January 2005): 707–8. http://dx.doi.org/10.1021/jo048509q.

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Sharma, Ashutosh, and Otto S. Wolfbeis. "Fiberoptic Oxygen Sensor Based on Fluorescence Quenching and Energy Transfer." Applied Spectroscopy 42, no. 6 (August 1988): 1009–11. http://dx.doi.org/10.1366/0003702884430470.

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A new type of oxygen sensor is described that is based on electronic energy transfer from a donor (whose fluorescence is efficiently quenched by molecular oxygen) to an acceptor (which is less affected by oxygen). We use pyrene as the donor and perylene as the acceptor. The fluorescence emission band of the donor shows good overlap with the absorption band of the acceptor. When excited at 320 nm, the two-fluorophore system shows strong fluorescence at 476 nm, where pyrene itself is nonfluorescent. Although perylene is not efficiently quenched by oxygen, the system strongly responds to oxygen because fluorescence is quenched with an efficiency that by far exceeds the quenching efficiency for pyrene or pyrelene alone. The principle has been applied in order to devise a fiberoptic oxygen sensor by incorporating the two dyes in a polymer matrix that has been attached to the end of an optical fiber. Oxygen can be detected in the 0–150 kPa range with ±0.3 kPa precision. The detection limit is 60 Pa oxygen.

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Jurković, Marta, Marijana Radić Stojković, Ksenija Božinović, Davor Nestić, Dragomira Majhen, Estefanía Delgado-Pinar, Mario Inclán, Enrique García-España, and Ivo Piantanida. "Novel Tripodal Polyamine Tris-Pyrene: DNA/RNA Binding and Photodynamic Antiproliferative Activity." Pharmaceutics 15, no. 9 (August 25, 2023): 2197. http://dx.doi.org/10.3390/pharmaceutics15092197.

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A novel tri-pyrene polyamine (TAL3PYR) bearing net five positive charges at biorelevant conditions revealed strong intramolecular interactions in aqueous medium between pyrenes, characterised by pronounced excimer fluorescence. A novel compound revealed strong binding to ds-DNA and ds-RNA, along with pronounced thermal stabilisation of DNA/RNA and extensive changes in DNA/RNA structure, as evidenced by circular dichroism. New dye caused pronounced ds-DNA or ds-RNA condensation, which was attributed to a combination of electrostatic interactions between 5+ charge of dye and negatively charged polynucleotide backbone, accompanied by aromatic and hydrophobic interactions of pyrenes within polynucleotide grooves. New dye also showed intriguing antiproliferative activity, strongly enhanced upon photo-induced activation of pyrenes, and is thus a promising lead compound for theranostic applications on ds-RNA or ds-DNA targets, applicable as a new strategy in cancer and gene therapy.

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Styler, S. A., M. E. Loiseaux, and D. J. Donaldson. "Substrate effects in the photoenhanced ozonation of pyrene." Atmospheric Chemistry and Physics Discussions 10, no. 11 (November 15, 2010): 27825–52. http://dx.doi.org/10.5194/acpd-10-27825-2010.

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Abstract. We report the effects of actinic illumination on the heterogeneous ozonation kinetics of solid pyrene films and pyrene adsorbed at air-octanol and air-aqueous interfaces. Upon illumination, the ozonation of solid pyrene films and pyrene at the air-aqueous interface proceeds more quickly than in darkness; no such enhancement is observed for pyrene at the air-octanol interface. Under dark conditions, the reaction of pyrene at all three interfaces proceeds via a Langmuir-Hinshelwood-type surface mechanism. In the presence of light, Langmuir-Hinshelwood kinetics are observed for solid pyrene films but a linear dependence upon gas-phase ozone concentration is observed at the air-aqueous interface. We interpret these results as evidence of the importance of charge-transfer pathways for the ozonation of excited-state pyrene. The dramatically different behaviour of pyrene at the surface of these three simple reaction environments highlights the difficulties inherent in representing complex reactive surfaces in the laboratory, and suggests caution in extrapolating laboratory results to environmental surfaces.

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Styler, S. A., M. E. Loiseaux, and D. J. Donaldson. "Substrate effects in the photoenhanced ozonation of pyrene." Atmospheric Chemistry and Physics 11, no. 3 (February 14, 2011): 1243–53. http://dx.doi.org/10.5194/acp-11-1243-2011.

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Qutob, Mohammad, Mohd Rafatullah, Syahidah Akmal Muhammad, Abeer M. Alosaimi, Hajer S. Alorfi, and Mahmoud A. Hussein. "A Review of Pyrene Bioremediation Using Mycobacterium Strains in a Different Matrix." Fermentation 8, no. 6 (May 31, 2022): 260. http://dx.doi.org/10.3390/fermentation8060260.

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Polycyclic aromatic hydrocarbons are compounds with 2 or more benzene rings, and 16 of them have been classified as priority pollutants. Among them, pyrene has been found in higher concentrations than recommended, posing a threat to the ecosystem. Many bacterial strains have been identified as pyrene degraders. Most of them belong to Gram-positive strains such as Mycobacterium sp. and Rhodococcus sp. These strains were enriched and isolated from several sites contaminated with petroleum products, such as fuel stations. The bioremediation of pyrene via Mycobacterium strains is the main objective of this review. The scattered data on the degradation efficiency, formation of pyrene metabolites, bio-toxicity of pyrene and its metabolites, and proposed degradation pathways were collected in this work. The study revealed that most of the Mycobacterium strains were capable of degrading pyrene efficiently. The main metabolites of pyrene were 4,5-dihydroxy pyrene, phenanthrene-4,5-dicarboxylate, phthalic acid, and pyrene-4,5-dihydrodiol. Some metabolites showed positive results for the Ames mutagenicity prediction test, such as 1,2-phenanthrenedicarboxylic acid, 1-hydroxypyrene, 4,5-dihydropyrene, 4-phenanthrene-carboxylic acid, 3,4-dihydroxyphenanthrene, monohydroxy pyrene, and 9,10-phenanthrenequinone. However, 4-phenanthrol showed positive results for experimental and prediction tests. This study may contribute to enhancing the bioremediation of pyrene in a different matrix.

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KUMARI, BEEMA, and RAM CHANDRA. "A Review on Bacterial Degradation of Benzo[a]pyrene and Its Impact on Environmental Health." Journal of Experimental Biology and Agricultural Sciences 10, no. 6 (December 31, 2022): 1253–65. http://dx.doi.org/10.18006/2022.10(6).1253.1265.

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Benzo[a]pyrene is a polycyclic aromatic hydrocarbon (PAH) having a high molecular weight. Benzo[a]pyrene and other PAHs are induces severe acute or chronic human health hazards and are extremely carcinogenic, mutagenic, immunotoxic, and teratogenic. Microorganisms play a crucial part in the degradation of benzo[a]pyrene from polluted environments. Such micro-organisms synthesize monooxygenase and di-oxygenase enzymes that proceed with the aerobic or anaerobic catabolic degradations of benzo[a]pyrene. Bioaugmentation, biomineralization, and biostimulation methods can be used for the decontamination of benzo[a]pyrene from hydrocarbon contaminated sites. In this review paper, we thoroughly explained the impacts of benzo[a]pyrene pollution on human health and the environment. Further, this study also described various pathways regarding the bio-degradation of benzo[a]pyrene and also an updated overview of future prospects of benzo[a]pyrene biodegradation.

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Launen, Loren, Linda Pinto, Christine Wiebe, Eberhard Kiehlmann, and Margo Moore. "The oxidation of pyrene and benzo[a]pyrene by nonbasidiomycete soil fungi." Canadian Journal of Microbiology 41, no. 6 (June 1, 1995): 477–88. http://dx.doi.org/10.1139/m95-064.

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The purpose of this study was to determine the ability of nonbasidiomycete soil fungi to oxidize pyrene (four rings) and benzo[a]pyrene (BaP) (five rings). Fungi were isolated from five different soils in which the polycyclic aromatic hydrocarbon content ranged from 0.8 to 80 μg/g dry soil. Approximately 50% of the isolates in all sites were able to oxidize pyrene. The pyrene-oxidizing species belonged to all fungal divisions except basidiomycetes. The most common were Penicillium spp. of the subgenus Furcatum and these dominated the more contaminated soils. Penicillium janthinellum and Syncephalastrum racemosum exhibited the most rapid rates of pyrene oxidation. The major pyrene metabolites were identified by proton NMR and mass spectrometry as 1-pyrenol, 1,6- and 1,8-pyrenediol, and the 1,6- and 1,8-pyrenequinones. A high correlation was found between the ability to oxidize pyrene and BaP. As with pyrene, approximately 50% of the fungal isolates tested oxidized BaP to 9-hydroxy-BaP. Eighty percent of the pyrene-oxidizing strains were also able to metabolize BaP.Key words: fungi, polycyclic aromatic hydrocarbons, biotransformation, bioremediation, cytochrome P-450.

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Moriguchi, Tomohisa, Satomi Hida, Fumio Yoneda, and Kazuo Shinozuka. "Synthesis and Spectroscopic Properties of a Novel Bifunctional Pyrene Derivative and its Incorporation into OligoDNA." Australian Journal of Chemistry 68, no. 2 (2015): 256. http://dx.doi.org/10.1071/ch14477.

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A new pyrene derivative bearing a modifiable silyl function (electron-donating group) and cyano function (electron-withdrawing group) was synthesized as a labelling agent for biological substances. The modified pyrene exhibited a marked bathochromic shift in both absorption and fluorescence spectra. The fluorescence quantum yield of the modified pyrene was also significantly increased compared with that of the unmodified pyrene. The modified pyrene was successfully incorporated into oligoDNA.

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Cheng, Chih-Chia, Jyun-Jie Huang, Adem Ali Muhable, Zhi-Sheng Liao, Shan-You Huang, Shun-Chieh Lee, Chih-Wei Chiu, and Duu-Jong Lee. "Supramolecular fluorescent nanoparticles functionalized with controllable physical properties and temperature-responsive release behavior." Polymer Chemistry 8, no. 15 (2017): 2292–98. http://dx.doi.org/10.1039/c7py00276a.

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Kim, Seong-Jae, Jaekyeong Song, Ohgew Kweon, Ricky D. Holland, Dae-Wi Kim, Jongnam Kim, Li-Rong Yu, and Carl E. Cerniglia. "Functional Robustness of a Polycyclic Aromatic Hydrocarbon Metabolic Network Examined in anidAAromatic Ring-Hydroxylating Oxygenase Mutant of Mycobacterium vanbaalenii PYR-1." Applied and Environmental Microbiology 78, no. 10 (March 9, 2012): 3715–23. http://dx.doi.org/10.1128/aem.07798-11.

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ABSTRACTIn this study, we obtained over 4,000 transposon mutants ofMycobacterium vanbaaleniiPYR-1 and analyzed one of the mutants, 8F7, which appeared to lose its ability to degrade pyrene while still being able to degrade fluoranthene. This mutant was identified to be defective innidA, encoding an aromatic ring-hydroxylating oxygenase (RHO), known to be involved in the initial oxidation step of pyrene degradation. When cultured with pyrene as a sole source of polycyclic aromatic hydrocarbon (PAH), high-pressure liquid chromatography analysis revealed that thenidAmutant showed a significant decrease in the rate of pyrene degradation compared to the wild-type PYR-1, although pyrene was still being degraded. However, when incubated with PAH mixtures including pyrene, phenanthrene, and fluoranthene, the pyrene degradation rate of the mutant was higher than that of the mutant previously incubated with pyrene as a sole source of PAH. There was no significant difference between wild-type PYR-1 and the mutant in the rates of phenanthrene and fluoranthene degradation. From the whole-cell proteome analysis of mutant 8F7 induced by pyrene, we identified expression of a number of RHO enzymes which are suspected to be responsible for pyrene degradation in thenidAmutant, which had no expression of NidA. Taken together, results in this study provide direct evidence for thein vivofunctional role ofnidAin pyrene degradation at the level of the ring-cleavage-process (RCP) functional module but also for the robustness of the PAH metabolic network (MN) to such a genetic perturbation.

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LAZCANO-FLORES, EDUARDO, and ALEJANDRO TORRES-MONTÚFAR. "Palicourea or Mexocarpus? Molecular phylogenetics of a Mesoamerican genus (Palicoureeae, Rubiaceae)." Phytotaxa 700, no. 2 (May 8, 2025): 205–22. https://doi.org/10.11646/phytotaxa.700.2.4.

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One of the most conflicting groups among Rubiaceae is related to Psychotria-Palicourea, which has always been a subject of debate among taxonomists due to its high number of species, its paraphyly, and its morphological variation. The genus Mexocarpus was described to encompass Palicourea tetragona due to its pyrenes with prominent ridges, atypical within the rest of Palicourea species. Mexocarpus is a genus distributed from southern Mexico to Central America, aside the pyrene morphology is characterized by the long white flowers with nocturnal anthesis and the fruits tetragonal when dry. The species was originally published as Cephaelis, then transferred to Palicourea and finally to Mexocarpus, however, this latter transfer is not accepted by some researchers arguing that the pyrene morphology is variable. We conducted phylogenetic analyses using two nuclear markers (ETS and ITS) and one plastid marker (trnL-F) to test the phylogenetical position of Mexocarpus tetragona. Our molecular phylogeny shows that Mexocarpus tetragonus does not form a separate entity from Palicourea, forming an unresolved clade with Palicourea tomentosa and Palicourea faxlucens. Additionally, the morphological comparison with closely related species indicates that pyrene morphology is highly variable and therefore cannot be used as a diagnostic character to segregate a genus within this complex. Then, based on morphology and molecular evidence our conclusion is not recognize Mexocarpus as a separate genus.

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Lange, Bettina, Stefan Kremer, Heidrun Anke, and Olov Sterner. "Metabolism of pyrene by basidiomycetous fungi of the generaCrinipellis,Marasmius, andMarasmiellus." Canadian Journal of Microbiology 42, no. 11 (November 1, 1996): 1179–83. http://dx.doi.org/10.1139/m96-151.

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The ability of different species and strains of the genus Crinipellis and the related genera Marasmius and Marasmiellus to metabolize pyrene was investigated. The metabolism of pyrene and the nature of metabolites formed were strain specific and depended on the culture medium. The following metabolites of pyrene were detected in the cultures: 1-hydroxypyrene, 1-pyrenylsulfate, 1,6- and 1,8-dihydroxypyrene and the corresponding quinones, trans-4,5-dihydro-4,5-dihydroxypyrene, and two transformation products which have never before been detected, 6-hydroxypyrene-1-sulfate and pyrene-1,6-disulfate. In addition, several not yet identified pyrene metabolites were produced by some strains.Key words: polycyclic aromatic hydrocarbons, pyrene, basidiomycetes, metabolism, transformation products.

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Stefansson, Steingrimur, Lára A. Stefansson, Suk-won Chung, Kevin Ko, Hena H. Kwon, and Saeyoung Nate Ahn. "Evaluation of Aromatic Boronic Acids as Ligands for Measuring Diabetes Markers on Carbon Nanotube Field-Effect Transistors." Journal of Nanotechnology 2012 (2012): 1–6. http://dx.doi.org/10.1155/2012/371487.

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Biomolecular detections performed on carbon nanotube field-effect transistors (CNT-FETs) frequently use reactive pyrenes as an anchor to tether bioactive ligands to the hydrophobic nanotubes. In this paper, we explore the possibility of directly using bioactive aromatic compounds themselves as CNT-FET ligands. This would be an efficient way to functionalize CNT-FETs since many aromatic compounds bind avidly to nanotubes, and it would also ensure that ligand-binding molecules would be brought in close proximity to the nanotubes. Using a model system consisting of pyrene, phenanthrene, naphthalene, or phenyl boronic acids immobilized on CNT-FET wafers, we show that all are able to bind glycated human serum albumin (gHSA), which is an important diabetes marker. Pyrene boronic acid proved to bind CNTs with the greatest apparent affinity as measured by gHSA impedance. Interestingly, gHSA CNT-FET signal intensity, which is proportional to amount of protein bound, remained essentially unchanged for all the boronic acids tested.

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Jadhav, Sushilkumar. "Synthesis of fluorescent carboxylic acid ligands for construction of monolayers on nanostructures." Open Chemistry 10, no. 5 (October 1, 2012): 1640–46. http://dx.doi.org/10.2478/s11532-012-0078-2.

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AbstractTwo new long-chain carboxylic acids (1, 2) bearing strong fluorescent group pyrene as ligands for Self-Assembled Monolayers (SAMs) have been synthesized. The multistep targeted synthesis is accomplished by use of Pyren-1-yl methylamine hydrochloride and employing simplified synthetic protocols. Compound 2 contains a chiral center purposely introduced along the atom chain in order to make it suitable for chiro-optical studies of the resulting SAMs.

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Xiao, Hang, Tao Li, Xiao-Li Sun, Wen-Ming Wan, Hongli Bao, Qingrong Qian, and Qinghua Chen. "Unpredicted Concentration-Dependent Sensory Properties of Pyrene-Containing NBN-Doped Polycyclic Aromatic Hydrocarbons." Molecules 27, no. 1 (January 5, 2022): 327. http://dx.doi.org/10.3390/molecules27010327.

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Pyrene molecules containing NBN-doped polycyclic aromatic hydrocarbons (PAHs) have been synthesized by a simple and efficient intermolecular dehydration reaction between 1-pyrenylboronic acid and aromatic diamine. Pyrene-B (o-phenylenediamine) with a five-membered NBN ring and pyrene-B (1,8-diaminonaphthalene) with a six-membered NBN ring show differing luminescence. Pyrene-B (o-phenylenediamine) shows concentration-dependent luminescence and enhanced emission after grinding at solid state. Pyrene-B (1,8-diaminonaphthalene) exhibits a turn-on type luminescence upon fluoride ion addition at lower concentration, as well as concentration-dependent stability. Further potential applications of Pyrene-B (o-phenylenediamine) on artificial light-harvesting film were demonstrated by using commercial NiR dye as acceptor.

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Will, A. Yvette, Arsenio Muñoz De La Peña, Thilivhali T. Ndou та Isiah M. Warner. "Influence of Triethanolamine on Aqueous β-Cyclodextrin/Pyrene Complexes". Applied Spectroscopy 49, № 4 (квітень 1995): 520–25. http://dx.doi.org/10.1366/0003702953964192.

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The influence of triethanolamine (TEA) on the aqueous β-CD/pyrene fluorescence is examined. Collisional quenching of pyrene by TEA is indicated by Stern-Volmer plots. However, a decrease in the quenching is observed in the presence of β-cyclodextrin, which indicates an effective protection of the included pyrene molecules against quenching from TEA. A decrease in the apparent formation constant of the β-CD/pyrene complex also occurs in the presence of TEA. This phenomenon is attributed to a combination of an increased bulk solvent hydrophobicity and a competitive equilibrium between pyrene and TEA for the β-CD cavity. The present study indicates that TEA is not co-included in the β-CD/pyrene complex.

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Oliveira, A. S., L. F. Vieira Ferreira, J. P. Da Silva, and J. C. Moreira. "Surface photochemistry: Photodegradation study of pyrene adsorbed onto microcrystalline cellulose and silica." International Journal of Photoenergy 6, no. 4 (2004): 205–13. http://dx.doi.org/10.1155/s1110662x04000261.

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Ground-state diffuse reflectance, time resolved laser-induced luminescence, diffuse reflectance laser flash-photolysis transient absorption and chromatographic techniques were used to elucidate the photodegradation processes of pyrene adsorbed onto microcrystalline cellulose and silica. Ground-state diffuse reflectance showed that on both substrates low concentrations display absorption of pyrene monomers. At high concentrations spectral changes attributed to aggregate formation were observed. Laser induced fluorescence showed that pyrene onto microcrystalline cellulose mainly presents fluorescence from monomers, while for silica, excimer-like emission was observed from low surface loadings (≥0.5μmolg−1). Transient absorption and photodegradation studies were performed at concentrations where mainly monomers exist. On silica, pyrene presents transient absorption from its radical cation. On microcrystalline cellulose both radical cation, radical anion and pyrene triplet-triplet absorption were detected. Irradiation followed by chromatographic analysis showed that pyrene decomposes on both substrates. For pyrene on microcrystalline cellulose 1-hydroxypyrene was the main identified photoproduct since in the absence of oxygen further oxidation of 1-hydroxypyrene was very slow. For pyrene on silica photodegradation was very efficient. Almost no 1-hydroxypyrene was detected since in the presence of oxygen it is quickly oxidized to other photooxidation products. On both substrates, pyrene radical cation is the intermediate leading to photoproducts and oxygen it is not involved in its formation.

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Ma, Jin-Kui, Walaa Fathy Saad Eldin, Waleed Rizk El-Ghareeb, Abdelazim Elsayed Elhelaly, Mariam H. E. Khedr, Xiang Li, and Xiao-Chen Huang. "Effects of Pyrene on Human Liver HepG2 Cells: Cytotoxicity, Oxidative Stress, and Transcriptomic Changes in Xenobiotic Metabolizing Enzymes and Inflammatory Markers with Protection Trial Using Lycopene." BioMed Research International 2019 (October 9, 2019): 1–10. http://dx.doi.org/10.1155/2019/7604851.

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Pyrene is one of the major polycyclic aromatic hydrocarbons formed during heat treatment of meat and in car exhausts; however, few studies have investigated pyrene-induced adverse effects on human cell lines. This study aimed at the investigation of pyrene-induced cytotoxicity and oxidative damage in human liver HepG2 cells at environmentally relevant concentrations. Pyrene-induced changes in mRNA expression of xenobiotic metabolizing enzymes (XMEs), xenobiotic transporters, antioxidant enzymes, and inflammatory markers were investigated using real-time PCR. As a protection trial, the ameliorative effects of lycopene, a carotenoid abundantly found in tomato, were investigated. The possible mechanisms behind such effects were examined via studying the co exposure effects of pyrene and lycopene on regulatory elements including the aryl hydrocarbon receptor (Air) and elytroid 2-related factor 2 (RF). The achieved results indicated that pyrene caused significant cytotoxicity at 50 n, with a clear production of reactive oxygen species (ROS) in a dose-dependent manner. Pyrene upregulated mRNA expression of phase I enzymes including CYP1A1, 1A2, and CYP1B1 and inflammatory markers including TNFα and Cox2. However, pyrene significantly downregulated phase II enzymes, xenobiotic transporters, and antioxidant enzymes. Interestingly, lycopene significantly reduced pyrene-induced cytotoxicity and ROS production. Moreover, lycopene upregulated detoxification and antioxidant enzymes, probably via its regulatory effects on Air- and RF-dependent pathways.

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Kucera, Benjamin E., Robert E. Jilek, William W. Brennessel, and John E. Ellis. "Bis(pyrene)metal complexes of vanadium, niobium and titanium: isolable homoleptic pyrene complexes of transition metals." Acta Crystallographica Section C Structural Chemistry 70, no. 8 (July 4, 2014): 749–53. http://dx.doi.org/10.1107/s2053229614015290.

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Reduction of VCl3(THF)3(THF is tetrahydrofuran) and NbCl4(THF)2by alkali metal pyrene radical anion salts in THF affords the paramagnetic sandwich complexes bis[(1,2,3,3a,10a,10b-η)-pyrene]vanadium(0), [V(C16H10)2], and bis[(1,2,3,3a,10a,10b-η)-pyrene]niobium(0), [Nb(C16H10)2]. Treatment of tris(naphthalene)titanate(2−) with pyrene provides the isoelectronic titanium species, isolated as an (18-crown-6)potassium salt, namelycatena-poly[[(18-crown-6)potassium]-μ-[(1,2-η:1,2,3,3a,10a,10b-η)-pyrene]-titanate(−I)-μ-[(1,2,3,3a,10a,10b-η:6,7-η)-pyrene]], {[K(C12H24O6)][Ti(C16H10)2]}n. The first two compounds have very similar packing, with neighboring molecules arranged orthogonally to one another, such that aromatic donor–acceptor interactions are likely responsible for the specific arrangement. The asymmetric unit contains a half-occupancy metal center η6-coordinated to one pyrene ligand, with the fullM(pyrene)2molecule generated by a crystallographic inversion center. In the titanium compound, the cations and anions are in alternating contact throughout the crystal structure, in one-dimensional chains along the [101] direction. As in the other two compounds, the asymmetric unit contains a half-occupancy Ti atom η6-coordinated to one pyrene ligand. Additionally, the asymmetric unit contains one half of an (18-crown-6)potassium cation, located on a crystallographic inversion center coincident with the K atom. The full formula units are generated by those inversion centers. In all three structures, the pyrene ligands are eclipsed and sandwich the metals in one of two inversion-related sites. These species are of interest as the first isolable homoleptic pyrene transition metal complexes to be described in the scientific literature.

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Vo-Dinh, T., T. Nolan, Y. F. Cheng, M. J. Sepaniak, and J. P. Alarie. "Phase-Resolved Fiber-Optics Fluoroimmunosensor." Applied Spectroscopy 44, no. 1 (January 1990): 128–32. http://dx.doi.org/10.1366/0003702904085859.

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This paper describes the development and application of a phase-resolved fiber-optics fluoroimmunosensor (PR-FIS), which combines the biochemical specificity of antigen-antibody reaction, the high sensitivity of laser excitation, the versatility of fiber-optics sensors, and the selectivity of phase-resolved detection. The PR-FIS device can differentiate benzo(a)pyrene and benzo(a)pyrene tetrol, a DNA-adduct product of the carcinogen benzo(a)pyrene. Benzo(a)pyrene tetrol can be detected at femtomole levels in the presence of an amount of interfacing benzo(a)pyrene that is 50-fold more concentrated.

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Cummings, Elizabeth A., Thilivhali T. Ndou, Vonda K. Smith, and Isiah M. Warner. "Spectroscopic Study of the Ternary Complex of Beta-Cyclodextrin, Pyrene, and Triton X-100." Applied Spectroscopy 47, no. 12 (December 1993): 2129–34. http://dx.doi.org/10.1366/0003702934066523.

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The increased fluorescence intensity of pyrene due to indirect excitation by the nonionic surfactant Triton X-100 is discussed. Sensitization is quantitatively shown to occur in mixed solutions of pyrene, Triton X-100, and β-cyclodextrin (β-CD). A ternary complex is formed below the critical micelle concentration (CMC). Above the CMC, pyrene is displaced from the β-CD cavity. This is accompanied by a subsequent incorporation of pyrene into the interior of the micelle. Evidence is given that ternary complexation occurs among pyrene, CD, and TX-100.

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Shmal’ko, Akim V., Sergey A. Anufriev, Kyrill Yu Suponitsky, Evgeniia P. Antoshkina, Igor B. Sivaev, and Vladimir I. Bregadze. "Synthesis of B-Substituted Anthracenyl and Pyrenyl Derivatives of ortho-Carborane." Inorganics 13, no. 5 (April 27, 2025): 138. https://doi.org/10.3390/inorganics13050138.

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Isomeric B-substituted anthracenyl and pyrenyl derivatives of ortho-carborane containing polycyclic aromatic substituents both in the position of the carborane cage most distant from the carbon atoms (position 9) and in the neighboring position (position 3) were synthesized by Pd-catalyzed cross-coupling of the corresponding iodo derivatives of ortho-carborane with polycyclic aryl zinc bromides. The derivative containing two pyrenyl substituents at the positions most distant from the carbon atoms of the ortho-carborane cage, 9,12-di(pyren-1′-yl)-ortho-carborane, was obtained in a similar way starting from 9,12-diiodo-ortho-carborane. The solid-state structures of the pyrene-containing derivatives 3-pyren-1′-yl-ortho-carborane, 9-pyren-1′-yl-ortho-carborane, and 9,12-di(pyren-1′-yl)-ortho-carborane were determined by single-crystal X-ray diffraction.

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