3428-24-8Relevant articles and documents
Selective Vicinal Diiodination of Polycyclic Aromatic Hydrocarbons
Bolte, Michael,Jin, Tao,John, Alexandra,Kaehler, Tanja,Lerner, Hans-Wolfram,Wagner, Matthias
supporting information, p. 5847 - 5851 (2020/09/09)
Vicinally diiodinated polycyclic aromatic hydrocarbons (I2-PAHs) are accessible from the corresponding diborylated B2-PAHs through boron/iodine exchange. The B2-PAHs have been prepared via twofold electrophilic borylation reactions templated by a vicinally disilylated benzene. Our protocol is applicable to fluorenes, acenes, annulated acenes, oligoaryls, and even [5]helicene. Using B2-naphthalene as the example, we have shown that the reaction scope can, in principle, be expanded to include the synthesis of vicinally dibrominated and dihydroxylated PAHs. The usefulness of the building blocks provided by our method in the field of optoelectronic materials was demonstrated by the successful conversion of I2-fluoranthene to the analogous doubly alkynylated fluoranthene emitter.
Hydrogen bonding promoted simple and clean photo-induced reduction of C-X bond with isopropanol
Cao, Dawei,Yan, Chaoxian,Zhou, Panpan,Zeng, Huiying,Li, Chao-Jun
supporting information, p. 767 - 770 (2019/01/21)
We herein report a simple and clean photo-induced metal-free reduction of C-X bond under an atmosphere of air at room temperature. Isopropanol is used as both the reducing reagent and solvent. Various functional groups (acids, esters, alcohols, anilines, phenols, indoles, pyridines, cyano and trifluoromethyl groups) and other heterocyclic compounds are tolerated. Different organic halides (including C-I, C-Br and C-Cl bonds) can be dehalogenated with moderate to excellent yields. Polyhalides are also reduced chemoselectively and efficiently. DFT calculation suggests a six-membered ring transition state via C-X H-O hydrogen bonding to decrease the activation energy.
5-AMINO-4-CARBAMOYL-PYRAZOLE COMPOUNDS AS SELECTIVE AND IRREVERSIBLE T790M OVER WT-EGFR KINASE INHIBITORS AND USE THEREOF????
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Paragraph 0097, (2016/03/13)
Disclosed are compounds of Formula (I), pharmaceutical compositions comprising the same, processes for the preparation thereof, and the use thereof.
Photocatalytic degradation of lindane by polyoxometalates: Intermediates and mechanistic aspects
Antonaraki,Triantis,Papaconstantinou,Hiskia
experimental part, p. 119 - 124 (2010/08/22)
The photocatalytic degradation of lindane (γ-1,2,3,4,5,6-hexachlorocyclohexane) has been studied in the presence of the polyoxometalate PW12O403- in aqueous solutions. Lindane is fully decomposed to CO2, Cl- and H2O, while a great variety of intermediates has been detected using GC-MS, including aromatic compounds (dichlorophenol, trichlorophenols, tetrachlorophenol, hexachlorobenzene, di- and trichloro-benzenodiol), non-aromatic cyclic compounds (penta-, tetrachlorocyclohexene, heptachlorocyclohexane), aliphatic compounds (tetrachloroethane) and condensation products (polychlorinated biphenyls). The number and nature of the intermediates implies that the mechanism of decomposition of lindane is based on both oxidative and reductive processes. Common intermediates have been reported during photolysis of lindane in the presence of titanium dioxide. A similar overall mechanism of polyoxometalates and TiO2 photocatalysis through the formation of common reactive species is suggested.
Metabolism of polychlorinated dibenzo-p-dioxins by rat liver microsomes
Hu, Keke,Bunce, Nigel J.
, p. 307 - 315 (2007/10/03)
The in vitro metabolism of several chlorinated dibenzo-p-dioxin congeners (PCDDs) was studied using rat liver microsomes as a source of CYP 1 enzymes. The reactions were kinetically first order in both enzyme and substrate and showed a general trend toward decreasing reactivity with increasing chlorination. Michaelis-Menten kinetics were followed for 1-chlorodibenzo-p-dioxin (1-CDD); the reactivity of the enzyme preparation toward 1-CDD exactly paralleled its activity toward 7-ethoxyresorufin. The unreactive congeners 1,2,3,7,8-pentachlorodibenzo-p-dioxin (PeCDD) and 2,2′-dichlorobiphenyl (2,2′-DCB) acted as competitive inhibitors toward 1-CDD, with inhibition constants in the micromolar range, similar to the value of the Michaelis constant of 1-CDD. The inhibitory potency of f urafylline, a mechanism-based inhibitor that is selective for CYP 1A2, declined in the order acetanilide (standard) > 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) > 1-CDD. We conclude that 1-CDD and 1,2,3,4-TCDD are oxidized almost exclusively by CYP 1A1, whereas 2,3,7,8-TCDD and 1,2,4,7,8-PeCDD are oxidized mainly by CYP 1A2. 1,2,3,7,8-PeCDD was oxidized too slowly for us to reach any conclusion about the P450 isozyme responsible.
Novel terphenyls as selective cyclooxygenase-2 inhibitors and orally active anti-inflammatory agents
Li, James J.,Norton, Monica B.,Reinhard, Emily J.,Anderson, Gary D.,Gregory, Susan A.,Isakson, Peter C.,Koboldt, Carol M.,Masferrer, Jaime L.,Perkins, William E.,Seibert, Karen,Zhang, Yan,Zweifel, Ben S.,Reitz, David B.
, p. 1846 - 1856 (2007/10/03)
A novel series of terphenyl methyl sulfones and sulfonamides have been shown to be highly potent and selective cyclooxygenase-2 (COX-2) inhibitors. The sulfonamide analogs 17 and 21 were found to be much more potent COX-2 inhibitors and orally active anti-inflammatory agents than the corresponding methyl sulfone analogs 16 and 20, respectively, albeit with some decrease in COX-2 selectivity. Structure-activity relationship studies have determined that incorporation of two fluorine atoms in the central phenyl group, as in 20 and 21, is extremely advantageous for both in vitro COX-2 potency and selectivity as well as in vivo activity. Several noticeable examples in the 1,2-diaryl-4,5-difluorobenzenesulfonamide series are 21a-c,k,l,n (COX-2, IC50 = 0.002-0.004 μM), in which all have in vitro COX-1/COX-2 selectivity > 1000. In addition, sulfonamides 21a,b,d,g,j,m,n,q were shown to have greatly enhanced oral activity with more than 90% inhibition of prostaglandin E2 production in the air pouch model of inflammation. Furthermore, sulfonamide 21b was found to be very active in the rat adjuvant-induced arthritis model (ED50 = 0.05 mg/kg) and carrageenan-induced hyperalgesia assay (ED50 = 38.7 mg/kg) with no indication of gastrointestinal toxicity in rats at doses as high as 200 mg/kg.
Synthesis of nitropolychlorinated dibenzo-p-dioxins (NPCDDs) and their photochemical reaction with nucleophiles
Merica, Simona G.,Bunce, Nigel J.
, p. 826 - 834 (2007/10/03)
A series nitropolychlorodibenzo-p-dioxins (NPCDDs) was synthesized by condensation between catechols and 2,6-dinitrochalobenzene derivatives.In the presence of sodium ethoxide in anhydrous ethanol, these underwent photochemical SN2Ar* substitutions meta to the nitro group in high chemical yield and moderate quantum yield.Both ring-opening and chloride replacement reactions were observed.The reactions involved the triplet excited state of the NPCDD, and showed a linear relationship between Φ-1 and -1.Analogous reactions with KCN in methanol showed similar behaviour, but the products could not be isolated.Key words: photosubstitution, SN2Ar*, dibenzo-p-dioxins.
A Simple Method for the Preparation of Dichlorocatechols.
Kirsch, Nils H.,Stan, H.-J.
, p. 131 - 138 (2007/10/03)
Dichlorocatechols (DCC) are common metabolites in the aerobic degradation of dichlorobenzenes. Their synthesis is therefore possible either enzymatically, or chemically by several two-step-synthesis starting from cycloalkanones or suitable dichlorophenols. A modified ultrasonic Reimer/Tiemann reaction and subsequent Dakin oxidation was used to prepare 3,5-DCC and 4,5-DCC. A new UV-photoradical single step synthesis of 3,4-dichlorocatechol as well as 3,6-dichlorocatechol is described in detail. Mass spectral and 13C-NMR spectral data of all four dichlorocatechol isomers are presented.
N-Oxacyclic-alkylpiperidines as psychostimulants
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, (2008/06/13)
N-Oxacyclic-alkylpiperidyl-diazacompounds, e.g., those of the formula STR1 and salts thereof are antidepressants and psychostimulants.
Synthesis, X-ray structure determination, and formation of 3,4,5-trichloroquaiacol occuring in kraft pulp spent bleach liquors
Lindstroem, K.,Oesterberg, F.
, p. 815 - 822 (2007/10/02)
3,4,5-Trichloroquaiacol, which is formed during bleaching of chemical pulp and shown to bioaccumulate in fish, has been synthesized.The structure of the compound has been determined by means of X-ray analysis.The values of the 13C nmr chemical shifts and melting point differ from those previously reported.A reaction mechanism is suggested for the formation of 3,4,5- and 4,5,6-trichloroguaiacol.
