- A novel and convenient process for the selective oxidation of naphthalenes with hydrogen peroxide
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A practical ruthenium phase-transfer catalyst (Ru-PTC) system for the oxidation of naphthalene derivatives has been developed. Substituted 1,4-quinones are obtained in good selectivity and yield in water without the addition of any organic solvent and acid. By applying the optimized conditions the feed additive menadione (vitamin K3) is obtained from 2-methylnaphthalene with 64 % yield and 73 % selectivity.
- Shi, Feng,Tse, Man Kin,Beller, Matthias
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- Chlorination of quinonoid compounds using dichlorine monoxide
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Dichlorine monoxide is a selective reagent for the monochlorination at the active quinonoid position in benzoquinones and naphthoquinones.
- Thapliyal,Singh,Khanna
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- The preparation and characterization of a laccase nanogel and its application in naphthoquinone synthesis
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Laccase from Trametes versicolor 51639 was encapsulated on the nanoscale. The laccase nanogel was prepared by polyacrylamide encapsulation as a result of N-acryloxysuccinimide modification and in situ polymerization. Size-exclusion chromatography, fluorescence resonance energy transfer, dynamic light scattering, and transmission electron microscopy were employed to characterize the laccase nanogel. Higher thermal, pH, and storage stability and organic-solvent tolerance of the laccase nanogel were indicated without activity loss. Moreover, the laccase nanogel was used to synthesize naphthoquinones from hydroquinones with a 10-15% greater overall yield than that of native laccase. Copyright
- Jia, Honghua,Zhong, Chao,Huang, Fan,Wang, Chunming,Jia, Lisha,Zhou, Hua,Wei, Ping
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- Selective halogenation of 1,4-benzoquinones and 1,4-naphthoquinones with copper(II) halide adsorbed on alumina
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1,4-Benzoquinone or 1,4-naphthoquinone and their derivatives have been halogenated selectively at quinonoid positions with copper(II) halide adsorbed on neutral alumina followed by refluxing in halobenzene to give mono-, di-, tri- and tetra-haloquinones.
- Singh,Khanna
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- Iodine catalyzed chlorination of naphthoquinones using metal (II) chlorides
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The active quinonoid position of various naphthoquinones is chlorinated by metal(II) chloride (Cu/Hg) and iodine in acetic acid in single step reaction with excellent yields.
- Thapliyal, Prakash Chander
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- Ruthenium-catalyzed C-H oxygenation of quinones by weak O-coordination for potent trypanocidal agents
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Ruthenium-catalysis enabled the C-5 selective C-H oxygenation of naphthoquinones, and also sets the stage for the site-selective introduction of a hydroxyl group into anthraquinones. A-ring modified naphthoquinoidal compounds represent an important class of bioactive quinones for which the present study encompasses the first C-H oxygenation strategy by weak O-coordination.
- Dias, Gleiston G.,Rogge, Torben,Kuniyil, Rositha,Jacob, Claus,Menna-Barreto, Rubem F. S.,Da Silva Júnior, Eufranio N.,Ackermann, Lutz
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- Palladium-Catalysed Cross Coupling of Arylboronic Acids with 2-Chloro-1,4-naphthoquinones: The Synthesis of 2-Aryl- and 2,3-Bisaryl-1,4-naphthoquinones
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2-Chloro-1,4-naphthoquinones underwent palladium-catalysed cross coupling reactions with arylboronic acids to give the corresponding 2-aryl-1,4-naphthoquinones. Similarly, 2,3-dichloro-1,4-naphthoquinone underwent efficient cross coupling reactions with arylboronic acids to give mono or bis adducts. The required 2-chloro-1,4-naphthoquinones were conveniently prepared from the corresponding 2-hydroxy-1,4-naphthoquinones by treatment with oxalyl chloride.
- Best, Wayne M.,Sims, Colette G.,Winslade, Merilyn
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- REGIOSPECIFIC ADDITIONS OF SOME SIMPLE DIENES TO HALOQUINONES
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Some simple dienes have been shown to react regiospecifically with haloquinones; the adducts can be oxidized without loss of the oxygenated function or aromatized to a variety of natural products and useful intermediates.
- Boisvert, Louise,Brassard, Paul
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- Regiospecific Addition of Monooxygenated Dienes to Halo Quinones
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In spite of their decreased polarity with respect to previously studied electron-rich analogues, monooxygenated dienes also react regiospecifically with halo quinones.The corresponding adducts can easily be aromatized on silica gel to isomeric polysubstituted naphthoquinones of unambiguous structure and therefore provide ready access to substrates for subsequent regiospecific annulations.The scope of this approach is illustrated by advantageous syntheses of several natural products: chimaphilin, 6-methylalizarin, 6-methylxantopurpurin, and barleriaquinone.The adductscan also give rise to a series of products in which the oxygen function of the dienes is preserved as a hydroxyl group in the quinone.To this end adducts derived from 1-oxygenated dienes and halo quinones were oxidized effectively with Jones reagent while those obtained from the 2-oxygenated isomers responded better to manganese dioxide.Relative positions of substituens in the adducts were readily confirmed by comparison of some of the hydroxylated oxidation products with known compounds of unambiguous structure.The method is again illustrated by the ready synthesis of a number of natural products including plumbagin, soranjidiol, isochrysophanol and its 8-methyl ether, and isozyganein and its 5-methyl ether.
- Boisvert, Louise,Brassard, Paul
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- Electrochemical chlorination and bromination of electron-deficient C[sbnd]H bonds in quinones, coumarins, quinoxalines and 1,3-diketones
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The electrochemistry-promoted chlorination and bromination of electron-deficient C[sbnd]H bonds was developed, using quinones, coumarins, quinoxalines and 1,3-diketones. This protocol features readily available and safe halogen sources (hydrochloric acid and KBr), high site-selectivity and mild reaction conditions. It could provide an efficient access to a series of chlorinated and brominated quinones, coumarins, quinoxalines and 1,3-diketones.
- Yu, Dan,Ji, Ruixue,Sun, Zhihui,Li, Wenjie,Liu, Zhong-Quan
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supporting information
(2021/11/16)
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- Ligand-based design, synthesis and biochemical evaluation of potent and selective inhibitors of Schistosoma mansoni dihydroorotate dehydrogenase
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Schistosomiasis ranks second only to malaria as the most common parasitic disease worldwide. 700 million people are at risk and 240 million are already infected. Praziquantel is the anthelmintic of choice but decreasing efficacy has already been documented. In this work, we exploited the inhibition of Schistosoma mansoni dihydroorotate dehydrogenase (SmDHODH) as a strategy to develop new therapeutics to fight schistosomiasis. A series of quinones (atovaquone derivatives and precursors) was evaluated regarding potency and selectivity against both SmDHODH and human DHODH. The best compound identified is 17 (2-hydroxy-3-isopentylnaphthalene-1,4-dione) with IC50 = 23 ± 4 nM and selectivity index of 30.83. Some of the new compounds are useful pharmacological tools and represent new lead structures for further optimization.
- Calil, Felipe A.,David, Juliana S.,Chiappetta, Estela R.C.,Fumagalli, Fernando,Mello, Rodrigo B.,Leite, Franco H.A.,Castilho, Marcelo S.,Emery, Flavio S.,Nonato, M.Cristina
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p. 357 - 366
(2019/02/19)
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- A Copper Halide Promoted Regioselective Halogenation of Coumarins Using N-Halosuccinimide as Halide Source
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A safe, convenient, and regioselective synthesis of 3-halo coumarins using a metal halide (CuX 2 alone or with ZnX 2) promoted halogenation with N -halosuccinimide (NXS) as halide source is reported. The synthesis involved the steady in situ generation of highly reactive positive halogen (X +) by the coordination of copper or zinc with the N -halosuccinimide and subsequent electrophilic aromatic substitution of the electron-deficient coumarins. This procedure works well also for the halogenation of less electron-rich naphthoquinones, flavones, and methoxypsoralen in moderate to quantitative yields. This protocol features simple experimental conditions using readily available inexpensive reagents and provides a convenient approach to the chlorination or bromination of some useful heteroaromatic compounds.
- Su, Jinling,Zhang, Yan,Chen, Mingren,Li, Weiming,Qin, Xuewei,Xie, Yanping,Qin, Lixiao,Huang, Shihua,Zhang, Min
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supporting information
p. 630 - 634
(2019/03/08)
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- Method for preparing 2,3-dichloro-1,4-naphthoquinone from wastes in production process of 2-chloro-1,4-naphthoquinone
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The invention discloses a method for preparing 2,3-dichloro-1,4-naphthoquinone from wastes in the production process of a 2-chloro-1,4-naphthoquinone in the technical field of chemical industry. The method for preparing the 2,3-dichloro-1,4-naphthoquinone from the wastes in the production process of 2-chloro-1,4-naphthoquinone comprises the following specific steps: (S1) metering the wastes accumulated in production and feeding the wastes into a reaction kettle; (S2) feeding washed, centrifuged and dried materials into the reaction kettle again for discoloring treatment; (S3) carrying out detection through a GS gas chromatography analysis method; (S4) feeding pretreated tailings to the reaction bottle; (S5) adding industrial sodium acetate; and (S6) naturally cooling and stirring for about 30 minutes and then removing excessive chlorine. The 2,3-dichloro-1,4-naphthoquinone is prepared from waste residues generated in the production process of 2-chloro-1,4-naphthoquinone as a starting material through pretreatment and deep chlorination, so that the problem of waste residue emission is solved, the environment pressure is relieved, the environmental pollution is avoided and the production cost is reduced.
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Paragraph 0023
(2017/07/19)
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- The vicinal functionalization of olefins: A facile route to the direct synthesis of β-chlorohydrins and β-chloroethers
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An efficient and environmentally benign protocol for the synthesis of vicinal chlorohydroxy and chloromethoxy derivatives in a highly regioselective manner from olefins using NH4Cl as a chlorine source and oxone as an oxidant in aqueous acetone and methanol is demonstrated. This methodology offers an additive and metal chloride free approach and is endowed with simple reaction conditions, high yields a broad substrate scope and good functional group tolerance. Moreover, the aromatic substrates with a terminal double bond exhibited merely Markovnikov selectivity, while the internal alkenes show exclusive regiocontrol and low to moderate diastereoselectivity.
- Swamy, Peraka,Kumar, Macharla Arun,Reddy, Marri Mahender,Naresh, Mameda,Srujana, Kodumuri,Narender, Nama
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p. 26288 - 26294
(2014/07/08)
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- Total synthesis of cyclo-mumbaistatin analogues through anionic homo-fries rearrangement
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The structurally unique polyketide mumbaistatin is the strongest naturally occurring inhibitor of glucose-6-phosphate translocase-1 (G6P-T1), which is a promising target for drugs against type-2 diabetes mellitus and angiogenic processes associated with brain tumor development. Despite its high relevance, mumbaistatin has so far withstood all attempts towards its total synthesis. In the present study an efficient total synthesis of a deoxy-mumbaistatin analogue containing the complete carbon skeleton and a spirolactone motif closely resembling the natural product in its cyclized form was elaborated. Key steps of the synthesis are a Diels-Alder cycloaddition for the construction of the fully functionalized anthraquinone moiety and an anionic homo-Fries rearrangement to build up the tetra-ortho-substituted benzophenone core motif, from which a spiroketal lactone forms in a spontaneous process. The elaborated strategy opens an entry to a variety of new analogs of mumbaistatin and cyclo-mumbaistatin and may be exploited for the total synthesis of the natural product itself in the future.
- Neufeind, Stefan,Huelsken, Nils,Neudoerfl, Joerg-Martin,Schloerer, Nils,Schmalz, Hans-Guenther
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supporting information; experimental part
p. 2633 - 2641
(2011/04/16)
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- Laccase-generated quinones in naphthoquinone synthesis via Diels-Alder reaction
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The tandem synthesis of naphthoquinones was conducted from the reaction of laccase-generated quinones and acyclic dienes via Diels-Alder reaction. This reaction was carried out under mild condition in aqueous medium and yielded naphthoquinones up to 80%. In addition, the effect of solvent was also investigated and water was shown to be optimal for this reaction.
- Witayakran, Suteera,Zettili, Abdullah,Ragauskas, Arthur J.
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p. 2983 - 2987
(2008/02/04)
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- Synthesis of a mumbaistatin analogue through cross-coupling
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Studies on the total synthesis of mumbaistatin, the strongest natural inhibitor of G6P-T1, have culminated in the synthesis of a 4″,8-dideoxy analogue. Key steps include a Diels-Alder reaction for the construction of the functionalized anthraquinone, a palladium-catalyzed Stille coupling to generate a tetra-ortho-substituted diarylmethane, and a titanium-mediated alkynylation of an aldehyde to complete the carbon skeleton of mumbaistatin. Radical bromination of the methylene bridge afforded a lactone, which resembles the target structure in its cyclized form. Georg Thieme Verlag Stuttgart.
- Sucunza, David,Dembkowski, Daniel,Neufeind, Stefan,Velder, Janna,Lex, Johann,Schmalz, Hans-Günther
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p. 2569 - 2573
(2008/02/13)
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- The treatment of pests using substituted naphthoquinones
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Naphthoquinone compounds of the formula I wherein R1 and R2 are each, independently, selected from H and OH and R3 and R4 are each, independently, selected from H, halo and 1-4C alkyl groups, provided that when R1 and R2 are each H, R3 and R4 cannot both be H, have use as pesticides particularly in the treatment of acarids and insects. A pesticidal composition comprises at least one compound of the formula I together with an inert carrier.
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- Reactions of Polyhalogenated 4-Arylsulfonylimino-2-cyclohexenones and 3,6-Bis(arylsulfonylimino)cyclohexenes with Alcohols
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Polyhalogenated 4-arylsulfonylimino-2-cylohexenones and 3,6-bis(arylsulfonylimino)cyclohexenes react with alcohols to give 1,2-addition products at the C=N bond through intermediate formation of N-arylsulfonylimino-p-quinonimines. Heating of the adducts above the melting point results in elimination of alcohol molecule and formation of quinoid structures.
- Avdeenko, A. P.,Zhukova, S. A.
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p. 423 - 427
(2007/10/03)
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- Solid-state organic reactions proceeding by pulverization: Oxidation and halogenation with iodosobenzene and inorganic solid-supports
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Pulverization-activation method was employed to accelerate solid-state organic reactions. Crushing and grinding of solid mixtures of hydrogen halide-treated silica gels, iodosobenzene and organic substrates in the absence of a solvent brought about smooth and rapid reactions to give halogenated and/or oxidized products in good yields. Various sulfides were smoothly converted to sulfonyl chlorides in one step in excellent yields. The surface of silica gel activated by pulverization serves as a reaction field on which reagent molecules can effectively encounter with each other.
- Sohmiya, Hajime,Kimura, Takahide,Fujita, Mitsue,Ando, Takashi
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p. 13737 - 13750
(2007/10/03)
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- Use of thiazyl chlorides, alkyl carbamates, and thionyl chloride to fuse 1,2,5-thiadiazoles to quinones and to oxidize, chlorinate, and aminate them
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Thiazyl chlorides in a simple one-step procedure fuse 1,2,5-thiadiazole rings to quinones. So do alkyl carbamates mixed with excess thionyl chloride and pyridine. Evidence is put forward to support the hypothesis that NSCl or a related thiazyl derivative is the reactive species that brings about the transformations. Selenoyl chloride mixed with an alkyl carbamate, pyridine, and quinones similarly gives 1,2,5-selenodiazoloquinones. Thionyl chloride in pyridine chlorinates quinones and oxidizes hydroquinones. 2,3-Dichloro-1,4-quinones with S4N4 or with alkyl N-sulfinylcarbamates give 1,2,5-thiadiazoloquinones. Quinones and their 2,3-dichloro derivatives with TsNSO in pyridine give betaine derivatives of 2,3-diaminoquinones, which pyrrolidine converts into 2-amino-3-(tosylamino)quinones. A unified set of mechanisms is presented that accounts for these transformations.
- Shi,Katz,Yang,Liu
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p. 1285 - 1297
(2007/10/02)
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- CONDENSATION INDOLE/NAPHTHOQUINONE. SYNTHESE D'UNE NOUVELLE SERIE D'INDOLYL-1,4-NAPHTHOQUINONES
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Addition of an indole, which does not have a group at the 3-position, to 1,4-naphthoquinone leads to the expected 2-(3-indolyl)-1,4-naphthoquinone.When the 1,4-naphthoquinone is substituted at the 2-position by an alkyl or aryl group, the 2-substituted 3-(3-indolyl)-1,4-naphthoquinone is easily formed.However, when the 2-substituent of the quinone is functional (OH, OMe, Cl, Br, NC5H10, S-C6H5), in addition to the new series of expected indolylnaphthoquinones, several by-products resulting from elimination of the 2-substituted and/or further reaction of these compounds are formed.The outcome at the reaction appears to be very sensitive to the experimental conditions.
- Henrion, Jean-Christophe,Jacquet, Bernard,Hocquaux, Michel,Lion, Claude
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p. 163 - 168
(2007/10/02)
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- Naphthalene anti-psoriatic agents
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Psoriasis in mammals is relieved by topically administering naphthalenes of the formula: STR1 wherein: R1 is lower alkoxy or optionally substituted phenoxy; R2 is hydrogen, lower alkyl, optionally substituted phenyl or optionally substituted phenyl-lower-alkyl; R3 is hydrogen, lower alkyl, lower alkoxy, halo, optionally substituted phenyl, optionally substituted phenyl-lower-alkyl or optionally substituted phenyl-lower-alkoxy, and m is 1 or 2; X and Y are different and are selected from the group consisting of hydrogen, R4 and -C(O)W, wherein W is alkyl of one to seven carbon atoms, optionally substituted phenyl or optionally substituted benzyl; and R4 is lower alkyl or optionally substituted phenyl-lower-alkyl.
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- METHOD FOR TREATING DISEASE STATES IN MAMMALS WITH NAPHTHALENE LIPOXYGENASE-INHIBITTNG AGENTS
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Psoriasis in mammals is relieved by topically administering naphthalenes of the formula: wherein: R1 is lower alkoxy or optionally substituted phenoxy, R2 is the same as R1, or R2 is hydrogen, lower alkyl, optionally substituted phenyl or optionally substituted phenylalkyl, R3 is hydrogen, lower alkyl, lower alkoxy, halo, optionally substituted phenyl, optionally substituted phenyl-lower-alkyl or optionally substituted phenyl-lower-alkoxy, and m is 1 or 2; both X groups are the same and X is either -C(O)OR4 or -C(O)NR5R6 , wherein R4 is alkyl, phenyl or benzyl optionally substituted with one or two lower alkyl groups, lower alkoxy groups or halo; and R5 and R6 are independently hydrogen, lower alkyl, cycloalkyl or phenyl optionally substituted with one or two lower alkyl groups, lower alkoxy groups or halo. The compounds of this invention are also useful for the treatment of disease-states caused by lipoxygenase activity in mammals, particularly 5-lipoxygenase activity, when administered systemically.
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- Naphthalene anti-psoriatic agents
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Psoriasis in mammals is relieved by topically administering naphthalenes of the formula: STR1 wherein: R1 is alkoxy, alkylthio, optionally substituted phenoxy or optionally substituted phenylthio; R2 is hydrogen, lower alkyl, optionally substituted phenyl or optionally substituted phenylalkyl; R3 is lower alkyl, lower alkoxy, or halo and m is 0, 1 or 2, or R3 is optionally substituted phenyl, optionally substituted phenyl lower alkyl, optionally substituted phenyl lower alkoxy, amino, lower alkylamino, lower dialkylamino, cyano, or S(0)n R wherein R is lower alkyl; optionally substituted phenyl; optionally substituted phenyl lower alkyl; or optionally substituted heterocyclic aryl of three to nine ring atoms containing one or two heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, and the pharmaceutically acceptable acid addition salts thereof; and m is 1 and n is 0, 1 or 2; and W is alkyl of one to seven carbon atoms, optionally substituted phenyl or optionally substituted benzyl.
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- Naphthalene lipoxygenase-inhibiting agents
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Psoriasis in mammals is relieved by topically administering naphthalenes of the formula: STR1 wherein: R1 is lower alkoxy or optionally substituted phenoxy; R2 is hydrogen, lower alkyl, optionally substituted phenyl or optionally substituted phenylalkyl; R3 is hydrogen, lower alkyl, lower alkoxy, halo, optionally substituted phenyl, optionally substituted phenyl-lower-alkyl or optionally substituted phenyl-lower-alkoxy, and m is 1 or 2; X and Y are different and are either R4 or --C(O)W wherein R4 is lower alkyl or optionally substituted phenyl-lower-alkyl; W is --OR5 or --NR6 R7, wherein R5 is alkyl, optionally substituted phenyl or optionally substituted benzyl; and R6 and R7 are independently hydrogen, lower alkyl, cycloalkyl or optionally substituted phenyl. The compounds of this invention are also useful for the treatment of disease-states caused by lipoxygenase activity in mammals, particularly 5-lipoxygenase activity, when administered systemically.
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- Naphthalene anti-psoriatic agents
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Psoriasis in mammals is relieved by topically administering naphthalenes of the formula: STR1 wherein: R1 is lower alkoxy or optionally substituted phenoxy; R2 is hydrogen, lower alkyl, optionally substituted phenyl or optionally substituted phenylalkyl; R3 is hydrogen, lower alkyl, lower alkoxy, halo, optionally substituted phenyl, optionally substituted phenyl-lower-alkyl or optionally substituted phenyl-lower-alkoxy, and m is 1 or 2; X and Y are different and are either R4 or --C(O)W wherein R4 is lower alkyl or optionally substituted phenyl-lower-alkyl; W is --OR5 or --NR6 R7, wherein R5 is alkyl, optionally substituted phenyl or optionally substituted benzyl; and R6 and R7 are independently hydrogen, lower alkyl, cycloalkyl or optionally substituted phenyl.
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- Formation of Cyanide Ion or Cyanogen Chloride through the Cleavage of Aromatic Rings by Nitrous Acid or Chlorine. X. Pathway of Cyanogen Chloride Formation in the Reactions of 1-Naphthol and 4-Phenylimidazole with Chloramine
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The pathway in the formation of cyanogen chloride from the reaction of 1-naphthol (1) and 4-phenylimidazole with chloramine was investigated.The intermediates isolated in the reaction of 1-naphthol (1) with chloramine were N-chloro-1,2-naphthoquinone 2-imine (2) and o-carboxycinnamonitrile (6), the latter of which, liberating cyanogen chloride, was finally converted to phthalide-3-carboxylic acid (8).The products obtained in the reaction of 4-phenylimidazole (10) with chloramine were benzonitrile (14), benzoylformic acid (22) and benzoic acid (23) besides cyanogen chloride.Cyanogen chloride formed by the reaction of 4-methylimidazole with 15N>-chloramine was C14NCl.From these results the pathway of cyanogen chloride formation was elucidated.Keywords - cyanogen chloride; 1-naphthol; 4-phenylimidazole; histidine; chloramine; hypochlorous acid
- Ohya, Takeshi,Kanno, Saburo
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p. 4095 - 4102
(2007/10/02)
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- Mechanistic Studies on the Oxidation of Naphthalenes and Methylbenzenes to Quinones with H2O2 in the Presence of Pd(II) Catalysts
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The oxidation of naphthalenes and methylbenzenes to quinones with aqueous 60 percent hydrogen peroxide in the presence of a 0.24 percent Pd(II)-sulfonated polystyrene-type resin catalyst was studied.The presence of electron-donating substituents on carbon-2 of naphthalenes accelerated the oxidation. A reaction path by way of hydroxylated intermediates to the quinones is proposed.By using the MINDO/3 method, quantum chemical indices such as the superdelocalizability for electrophilic species (SEr) and for radical species (SRr), and the net charge (Qr) of naphthalenes, methylbenzenes, and naphthols were calculated.The activity in the above reaction could be explained in terms of both Qr and SEr.The decrease of the selectivity was correlated with side reactions by radical species attacking the sites of largest SRr.Keywords - oxidation; hydrogen peroxide; naphthalene; methylbenzene; palladium catalyst; 1,4-naphthoquinone; sulfonated polystyrene-type resin
- Yamaguchi, Satoru,Shinoda, Hiroyuki,Inoue, Masami,Enomoto, Saburo
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p. 4467 - 4473
(2007/10/02)
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- The Kinetics and Mechanisms of Additions to Olefinic Substances. Part 16. Addition of Halogens to 1,4-Benzoquinone and to 1,4-Naphthoquinone, and Dehydrohalogenation of the Resulting Adducts
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The products of acid catalysed halogenation of 1,4-benzoquinone and 1,4-naphthoquinone in acetic acid have been investigated under conditions which could lead to the formation of dichloride, dibromide, and bromochloride.The variation in ratio of bromochloride to dibromide with relative availability of bromine and chlorine as electrophile and nucleophile suggests that the first entering halogen atom is attached nucleophilically as the result of '1,4'- (rather than then '1,2'-) addition, and that the second halogen atom is then attached electrophilically.Acetate ion does not compete effectively with chloride ion in the nucleophilic stage of the reaction; and chlorine acetate does not add, even with sulphuric acid as catalyst, to 1,4-benzoquinone.The mechanistic significance of these results is discussed.The kinetics and products of solvolytic eliminations from the dihalides derived from 1,4-benzoquinone have been studied in 95percent ethanol; the effects of structure on the rate make it probable that the reactions lie towards the E1cB end of the spectrum of elimination mechanisms.
- Atkinson, Romily C.,Mare, Peter B. D. de la,Larsen, David S.
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p. 271 - 280
(2007/10/02)
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