- New cephalosporins and 7α-methoxy cephalosporins. Chemistry and biological activities
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The synthesis and the in vitro activity of a number of cephalosporins and 7α-methoxy cephalosporins having 7-acyl subsituents derived from 1-methyl-4 (or 5)-nitro-1H-imidazolyl-thioacetic acids are described. The microbiological profile is influenced by the position of both the nitro group and the side-chain sulfur atom on the 1-methyl imidazole, and by the nature of the 3-substituent.
- Elitropi,Panto,Tricerri,Chiarani,Pezzali,Riva,Zanuso
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- A Sandmeyer type reaction for bromination of 2-mercapto-1-methyl- imidazoline (N2C4H6S) into 2-bromo-1-methyl- imidazole (N2C4H5Br) in presence of copper(i) bromide
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2-Mercapto-1-methyl-imidazoline (N2C4H6S) is converted at room temperature into 2-bromo-1-methyl-imidazole (N 2C4H5Br) in presence of copper(i) bromide in acetonitrile-chloroform mixture via extrusion of sulfur as sulfate and oxidation of CuI into CuII. 2-Bromo-1-methyl-imidazole was isolated as its self assembled tetranuclear CuII cluster, [Cu 4(η1-N-(N2C4H 5Br)4(μ4-O)(μ-Br)6] 1 {η1-N-(N2C4H5Br) = 2-bromo-1-methyl-imidazole}.
- Lobana, Tarlok S.,Sultana, Razia,Butcher, Ray J.
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- Reaction of imidazoles with cyanogen bromide: Cyanation at N 1 or bromination at C 2?
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The reaction in acetonitrile solution of a number of imidazoles (1H-, 1-methyl-, 2-methyl-, 4-methyl-, 1,2-, 1,4- and 1,5-dimethyl-, 1-ethyl-, 1-benzyl- and 1-butyl-imidazole) and imidazole complexes ([Co(NH3)5(imH)](ClO4)3, [Co(NH3)5(im)] (ClO4)2 and [Co(NH3)5(1-Meim)] (ClO4)3) with BrCN has been studied. Those imidazoles bearing an N-alkyl substituent and having a hydrogen at C2 react to give the 2-bromo products, while the N-H imidazoles react to give W-cyano derivatives. The product(s) from the reaction of 1,2-dimethylimidazole with BrCN could not be characterized. Of the complexes, only [Co(NH3)5(im)] (ClO4)2 reacts, giving the 2-bromo product. Our observations suggest a lone pair on a ring nitrogen atom is necessary for an imidazole to react with BrCN, and a possible mechanism is suggested. The X-ray structure of 2-methylimidazole-1-carbonitrile is reported. Crystal data (-143°C) for C5H5N3: monoclinic, P21/c, a 10.201(5), b 7.110(3), c 7.227(3) A, β 100.47(2)°, V 515.4(4) A3, Z 4, dcalcd 1-380 g cm-3. Refinement of the structure converged with R1 0.0444 for 1183 reflections with Fo > 4F(Fo) and ωR2 0.1259 for all 1278 data.
- McCallum, Peter B.W.,Weavers, Rex T.,Grimmett, M. Ross,Blackman, Allan G.
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- Simple heteroatom engineering for tuning the triplet energy of organometallic host materials for red, green and blue phosphorescent organic light-emitting diodes
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Triplet energy tuning from 2.48 eV to 2.94 eV by just a simple change of heteroatom in the ligand structure of Be complexes was studied using azole based triplet host materials. Three Be organometallic host materials with azole type ligands were synthesized and could be used as the host materials from red to deep blue phosphorescent organic light-emitting diodes. High quantum efficiency was obtained in red, green, blue and deep blue devices using the Be complexes. In particular, a high quantum efficiency of 26.1% was achieved in blue phosphorescent organic light-emitting diodes.
- Oh, Chan Seok,Lee, Chil Won,Lee, Jun Yeob
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- Tetrahalogenomethanes: Simple reagents for the synthesis of monohalogenated and mixed dihalogenated aromatic heterocycles via metal-halogen exchange from lithium compounds
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Tetrabromo- or tetrachloromethane and 2-lithio derivatives of aromatic heterocycles rapidly produce the corresponding 2-bromo or 2-chloro derivatives in high yields through a metal-halogen exchange mechanism. This kind of reaction was also used to obtain, in good yields, 5-bromo-2-chlorothiazole and 5-bromo-2-chloro-N-methylimidazole.
- Boga, Carla,Del Vecchio, Erminia,Forlani, Luciano,Todesco, Paolo Edgardo
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- 1,5,7-TRISUBSTITUTED ISOQUINOLINE DERIVATIVES, PREPARATION THEREOF, AND USE THEREOF IN MEDICINES
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The present disclosure relates to 1,5,7-trisubstituted isoquinoline derivatives, their preparation and pharmaceutical use. In particular, the present disclosure discloses a compound of formula (I) or a pharmaceutically acceptable salt, stereoisomer, solvate or prodrug thereof, and a preparation method and use thereof. The definitions of the groups in the formula can be found in the specification and claims.
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Paragraph 0250-0251; 0291-0292
(2020/08/30)
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- PI4KIIIBETA INHIBITORS
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The invention relates to compounds of formula (I) which are inhibitors of kinase activity, pharmaceutical formulations containing the compounds and their uses in treating and preventing viral infections and disorders caused or exacerbated by the viral inf
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Page/Page column 58
(2019/08/08)
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- 2-Functionalized derivatives of 2-bromo-1,3-dimethylimidazole
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– Attempts at direct bromination of 1,3-dimethylimidazolium salts with bromine were futile. A tribromide or a carbene–lithium–THF adduct were received instead. The quaternary 2-bromo compound was obtained by methylation of 2-bromo-1-methylimidazole and subsequent ion metathesis, which was converted to the corresponding 2-cyano and 2-azido derivatives. Typical reactions of the latter include a dipolar cycloaddition and the Staudinger reaction. Crystal structures of eight compounds have been determined by single-crystal X-ray diffraction.
- Lampl, Martin,Laus, Gerhard,Wurst, Klaus,Kahlenberg, Volker,Gelbrich, Thomas,Nerdinger, Sven,Huppertz, Hubert,Schottenberger, Herwig
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p. 1116 - 1127
(2019/07/31)
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- T -BuONa-mediated direct C-H halogenation of electron-deficient (hetero)arenes
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An efficient halogenation of electron-deficient (hetero)arenes is described. The reaction utilizes common t-BuONa as a catalyst (for iodination) or a promoter (for bromination and chlorination), and perfluorobutyl iodide, CBr4 or CCl4 as the readily-available halogenating agents, respectively. The protocol features broad scope, high efficiency, mild conditions and gram scalability. An ionic pathway involving halogen bond formation and halophilic attack is proposed. The utility of the resulting iodinated heteroarenes is demonstrated in visible light-mediated Caryl-Caryl cross-coupling reaction.
- Liu, Xia,Zhao, Xin,Liang, Fushun,Ren, Baoyi
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supporting information
p. 886 - 890
(2018/02/19)
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- Method for preparing halogenated (hetero) aromatic hydrocarbons
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The invention relates to a method for preparing halogenated (hetero) aromatic hydrocarbons. The halogenated (hetero) aromatic hydrocarbons are prepared from cheap and easily available perfluorobutyl iodide, carbon tetrabromide and carbon tetrachloride as iodinated, brominated and chlorinated reagents respectively under the action of alkali catalysis (promotion). The method comprises the following steps: firstly, (hetero) aromatic hydrocarbons, a halogenated reagent and an inorganic base are placed in an organic solvent, stirred at room temperature and monitored with TLC until a substrate disappears, and the reaction is stopped; then, a reaction mixed solution is poured into water and extracted, an organic phase is dried, and the organic solvent is removed under reduced pressure; finally, silica-gel column chromatography is performed on a crude product, and a product is obtained. Purification can also be performed by recrystallization. The method has the advantages that the synthetic route is wide in substrate range, raw materials and reagents are cheap and easily available, operation is simple, conditions are mild, yield is high, energy consumption is reduced, the reaction route is safe, gram-grade preparation can be performed and the like.
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Paragraph 0055; 0056
(2018/03/24)
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- COMPOUND, ELECTROLUMINESCENT ELEMENT CONTAINING THE SAME, ILLUMINATING DEVICE AND DISPLAY DEVICE
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Provided are a novel compound, an organic EL element which contains such novel compound and has a high external extraction quantum efficiency and a long service life, an illuminating apparatus and a display apparatus.
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- Organic light emitting materials and devices
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An organic light emitting device is provided. The device has an anode, a cathode and an organic layer disposed between the anode and the cathode. The organic layer comprises a compound further comprising one or more arylimidazole, aryltriazole, or aryltet
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