1714-27-8Relevant academic research and scientific papers
Recognition of double-stranded DNA using energetically activated duplexes with interstrand zippers of 1-, 2- or 4-pyrenyl-functionalized O2′-alkylated RNA monomers
Karmakar, Saswata,Madsen, Andreas S.,Guenther, Dale C.,Gibbons, Bradley C.,Hrdlicka, Patrick J.
, p. 7758 - 7773 (2014)
Despite advances with triplex-forming oligonucleotides, peptide nucleic acids, polyamides and-more recently-engineered proteins, there remains an urgent need for synthetic ligands that enable specific recognition of double-stranded (ds) DNA to accelerate studies aiming at detecting, regulating and modifying genes. Invaders, i.e., energetically activated DNA duplexes with interstrand zipper arrangements of intercalator-functionalized nucleotides, are emerging as an attractive approach toward this goal. Here, we characterize and compare Invaders based on 1-, 2- and 4-pyrenyl-functionalized O2′-alkylated uridine monomers X-Z by means of thermal denaturation experiments, optical spectroscopy, force-field simulations and recognition experiments using DNA hairpins as model targets. We demonstrate that Invaders with +1 interstrand zippers of X or Y monomers efficiently recognize mixed-sequence DNA hairpins with single nucleotide fidelity. Intercalator-mediated unwinding and activation of the double-stranded probe, coupled with extraordinary stabilization of probe-target duplexes (ΔTm/modification up to +14.0 °C), provides the driving force for dsDNA recognition. In contrast, Z-modified Invaders show much lower dsDNA recognition efficiency. Thus, even very conservative changes in the chemical makeup of the intercalator-functionalized nucleotides used to activate Invader duplexes, affects dsDNA-recognition efficiency of the probes, which highlights the importance of systematic structure-property studies. The insight from this study will guide future design of Invaders for applications in molecular biology and nucleic acid diagnostics.
DOUBLE-DECKER SILSESQUIOXANE DERIVATIVE AND SYNTHESIZING METHOD THEREOF
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Paragraph 0061-0063, (2020/10/10)
A double-deck silsesquioxane derivative represented by chemical formula 1, a method for preparing the same, and an organic light emitting diode including the derivative are provided. Chemical Formula 1. R is the same as in the above formula. 1 Is a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group. R2 is possible. . Or. Me. (by machine translation)
Synthesis method of OLED intermediate 2-bromopyrene
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Paragraph 0050-0063, (2019/02/13)
The invention provides a synthesis method of OLED intermediate 2-bromopyrene. The method comprises the steps of firstly using 1-amino-2-bromopyrene as a raw material, using diazotization deamination method to obtain a 2-bromopyrene crude product; putting the 2-bromopyrene crude product ethyl acetate with a usage amount being 1.5 to 2.5 times by weight of the crude product, conducting heating to reflux, and then lowering the temperature to 20+/-2 DEG C to achieve crystallization, so as to achieve refining of the 2-bromopyrene crude product and finally obtain a 2-bromopyrene pure product with apurity of 99.5% or more. According to the invention, 1-amino-2-bromopyrene is used to prepare 2-bromopyrene, the yield is high, and the finally obtained 2-bromopyrene is high in purity. Meanwhile, theinvention provides a method of using 2-aminopyrene to react with a brominating reagent for prepare 1-amino-2-bromopyrene with a high yield, and the price of 1-aminopyrene is low. Compared with the prior art, the synthesis method disclosed by the invention can reduce the cost of preparing 2-bromopyrene.
new transition metal complex with annulated ring substituted arylphenoxy ligand, catalyst composition containing the same for olefin copolymerization and methods for preparing copolymers of ethylene and α-olefins or copolymers of ethylene and olefin-diene using the same
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Paragraph 0154; 0156-0157, (2018/10/04)
PURPOSE: A transition metal compound or a catalyst composition containing the compound is provided to enable easy and cheap preparation of the compound or the composition and to have copolymer reactivity with other olefins with a high catalytic activity at high temperature. CONSTITUTION: A transition metal compound is denoted by chemical formula 1. A transition metal catalyst composition for preparing a copolymer of ethylene and alpha-olefin or ethylene and olefin-diene contains: the transition metal compound; and an aluminum compound cocatalyst, a boron compound cocatalyst, or a mixture thereof. The cocatalyst is prepared using a transition metal catalyst composition.
Synthesis of 2-and 2,7-functionalized pyrene derivatives: An application of selective C-H borylation
Crawford, Andrew G.,Liu, Zhiqiang,Mkhalid, Ibraheem A. I.,Thibault, Marie-Helene,Schwarz, Nicolle,Alcaraz, Gilles,Steffen, Andreas,Collings, Jonathan C.,Batsanov, Andrei S.,Howard, Judith A. K.,Marder, Todd B.
, p. 5022 - 5035 (2012/05/20)
An efficient synthetic route to 2-and 2,7-substituted pyrenes is described. The regiospecific direct C-H borylation of pyrene with an iridium-based catalyst, prepared in situ by the reaction of [{Ir(μ-OMe)cod}2] (cod=1,5-cyclooctadiene) with 4,4′-di-tert-butyl-2,2′-bipyridine, gives 2,7-bis(Bpin)pyrene (1) and 2-(Bpin)pyrene (2, pin=OCMe 2CMe2O). From 1, by simple derivatization strategies, we synthesized 2,7-bis(R)-pyrenes with R=BF3K (3), Br (4), OH (5), B(OH)2 (6), and OTf (7). Using these nominally nucleophilic and electrophilic derivatives as coupling partners in Suzuki-Miyaura, Sonogashira, and Buchwald-Hartwig cross-coupling reactions, we obtained 2,7-bis(R)-pyrenes with R=(4-CO2C8H17)C6H4 (8), Ph (9), Ca≡CPh (10), Ca≡C[{4-B(Mes)2}C 6H4] (11), Ca≡CTMS (12), Ca≡C[(4-NMe 2)C6H4] (14), Ca≡CH (15), N(Ph)[(4-OMe)C6H4] (16), and R=OTf, R′=Ca≡CTMS (13). Lithiation of 4, followed by reaction with CO2, yielded pyrene-2,7-dicarboxylic acid (17), whilst borylation of 2-tBu-pyrene gave 2-tBu-7-Bpin-pyrene (18) selectively. By similar routes (including Negishi cross-coupling reactions), monosubstituted 2-R-pyrenes with R=BF3K (19), Br (20), OH (21), B(OH)2 (22), [4-B(Mes)2]C 6H4 (23), B(Mes)2 (24), OTf (25), Ca≡CPh (26), Ca≡CTMS (27), (4-CO2Me)C6H4 (28), Ca≡CH (29), C3H6CO2Me (30), OC 3H6CO2Me (31), C3H 6CO2H (32), OC3H6CO2H (33), and O(CH2)12Br (34) were obtained from 2. These derivatives are of synthetic and photophysical interest because they contain donor, acceptor, and conjugated substituents. The crystal structures of compounds 4, 5, 7, 12, 18, 19, 21, 23, 26, and 28-31 have also been obtained from single-crystal X-ray diffraction data, revealing a diversity of packing modes, which are described in the Supporting Information. A detailed discussion of the structures of 1 and 2, their polymorphs, solvates, and co-crystals is reported separately. Copyright
Medium-sized cyclophanes. Part 56. 8-substituted 5-tert-butyl [2.2] metaparacyclophane-1,9-dienes. Preparation, X-ray diffraction study and their treatment with Lewis and protic acids
Yamato,Noda,Tsuzuki
, p. 721 - 727 (2007/10/03)
The preparation of various 8-substituted 5-tert-butyl[2.2]metaparacyclophane-1,9-dienes 1, using the thiacyclophane method, and an X-ray diffraction study of 5-tert-butyl-8-cyano[2.2]metaparacyclophane-1,9-diene 1e are described. Lewis and protic acid-catalyzed reactions of 8-substituted [2.2]metaparacyclophane-1,9-dienes 1b-g in dichloromethane proceeded by isomerization and transannular cyclization to afford the strainless pyrenes 10 in good yields. In contrast, similar treatment of 5-tert-butyl-8-methoxy[2.2]metaparacyclophane 11 with Lewis acids in dichloromethane under the same conditions only led to recovery of the starting compound. Treatment of 8-methoxy[2.2]metaparacyclophane-1,9-diene 1d with TiCl4 in dichloromethane also led to isomerization and transannular reactions to afford 2-tert-butylpyrene 10b within 1 min in almost quantitative yield. However, the TiCl4 catalyzed reaction of an electron-poor [2.2]metaparacyclophane-1,9-diene such as 1e did not afford any product and the starting material was recovered in almost quantitative yield. These results suggest that the present novel isomerization reaction might be attributed to the bridged double bonds, which increase the strain in the molecule in comparison with the corresponding saturated [2.2]metaparacyclophane 11. The characterization and the reaction pathway of these products are also discussed.
Aryl acetylenes as mechanism-based inhibitors of cytochrome P450- dependent monooxygenase enzymes
Foroozesh, Maryam,Primrose, Ginny,Guo, Zuyu,Bell, L. Chastine,Alworth, William L.,Guengerich, F. Peter
, p. 91 - 102 (2007/10/03)
Aryl acetylenes have been investigated as inhibitors of cytochrome P450 (P450)-dependent alkoxyresorufin dealkylation activities in liver microsomes prepared from rats exposed to β-naphthoflavone, isosafrole, or phenobarbital. Many of the acetylenes investigated produce pseudo-first- order time-dependent and NADPH-dependent losses of the dealkylation activities characteristic of mechanism-based irreversible inactivation (suicide inhibition). Replacing the terminal hydrogen of aryl acetylenes with a methyl group to convert ethynes into propynes enhances the inhibition of P450 1A enzymes; in some instances, this modification converts a reversible inhibitor of P450s into a suicide inhibitor. In contrast, ethynes are more effective suicide inhibitors of P450 2B-dependent dealkylations than the corresponding propynes. Aryl acetylenes with an ethynyl group on the 2 position of naphthalene or on the 9 position of phenanthrene and arylalkyl acetylenes with alkyl chains containing 2, 3, or 4 methylene groups are selective inhibitors of P450 2B1/2B2 in liver microsomes from rats. Aryl acetylenes also act as suicide inhibitors of P450 1A2 in human liver microsomes, of purified P450 1A2 from rabbit or rat liver in reconstituted systems, and of purified recombinant human P450 1A2 and 1A1 in reconstituted systems. 4-(1-Propynyl)biphenyl (4PBi) inactivated P450 1A2-dependent ethoxyresourfin deethylation (EROD) activity in human liver microsomes in an NADPH-dependent process (k(inactivation), 0.23 min-1; K1, 2.3 μM). 4PBi also inactivated purified recombinant human P450 1A2 (k(inactivation), 0.24 min-1; K(I), 4.3 μM). In agreement with previous reports [Yun, C.-H., Hammons, G. J., Jones, G., Martin, M. V., Hopkins, N. E., Alworth, W. L., and Guengerich, F. P. (1992) Biochemistry 31, 10556-10563], 2-ethyny]naphthalene (2EN) was not a suicide inhibitor of the P450 1A2 activity in human liver microsomes but did inactivate purified human P450 1A2. Neither 4PBi nor 2EN affected diagnostic activities of human microsomal P450 2E1, 2C9/10, 3A4, or 2C19. In the systems examined, the losses of P450-dependent activity produced by these aryl acetylenes were not accompanied by corresponding decreases in the measured P450 absorption spectra. Thus P450 inactivation by these aryl acetylenes does not involve labeling and destruction of the heme. Incubation of 4PBi with microsomal P450 1A1 or 1A2 from rat liver under conditions that lead to P450-dependent enzyme inactivations generates a 2-biphenylylpropionic acid product. This suggests that the suicide inhibition of P450s by propynylaryl acetylenes proceeds via a methylaryl ketene formed by a 1,2- methyl rearrangement, analogous to the mechanism of suicide inhibition by ethynyl acetylenes that proceed via ketene intermediates formed by 1,2- hydrogen shifts [Ortiz de Montellano, P. R., and Kunze, K. L. (1981) Arch. Biochem. Biophys. 209, 710-712].
SYNTHESIS OF 2-BROMOPYRENE AND 2-HYDROXYPYRENE
Harvey, Ronald G.,Schmolka, Sanford,Cortez, Cecilia,Lee, Hongmee
, p. 2207 - 2210 (2007/10/02)
Regiospecific monobromination of 4,5,9,10-tetrahydropyrene in the 2-position is accomplished in aqueous dimethylformamide.Conversion of the previously unknown 2-bromo-4,5,9,10-tetrahydropyrene to the title compounds is described.
