- Chiral Imidodiphosphoric Acid-Catalyzed Highly Diastereo- and Enantioselective Synthesis of Poly-Substituted 3,4-Dihydro-2 H-pyrans: [4 + 2] Cycloadditions of β,γ-Unsaturated α-Ketoesters and 3-Vinylindoles
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Imidodiphosphoric acids were employed to catalyze inverse-electron-demand hetero-Diels-Alder reaction of β,γ-unsaturated α-ketoesters and 3-vinylindoles. A series of optically active 3,4-dihydro-2H-pyran derivatives with three contiguous stereogenic centers was synthesized in excellent yields (70-99%), diastereoselectivities (>20:1), and enantioselectivities (73-99%). The resulting indole containing 3,4-dihydro-2H-pyran could be converted to tetrahydropyran derivatives, which appear in several biological active compounds by simple hydrogenation reduction.
- Guan, Xu-Kai,Liu, Guo-Feng,An, Dong,Zhang, Heng,Zhang, Suo-Qin
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supporting information
p. 5438 - 5442
(2019/08/01)
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- Synthesis of aryl and heterocyclic polyenes and their activity in free radical scavenging
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Aryl polyenes and heterocyclic polyenes with the same central C20 unit of β,β-carotene but different terminal groups were synthesised. Their free radical scavenging activity was measured by a 1,1-diphenyl-2-picrylhydrazinyl spectrophotometric method. The results indicated that all the new compounds have free radical scavenging activity.
- Deng, Kaini,Yang, Zuxing,Luo, Juan,Wu, Kaiqun
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p. 129 - 132
(2018/04/20)
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- Ionic Liquids as Solvents for SN2 Processes. Demonstration of the Complex Interplay of Interactions Resulting in the Observed Solvent Effects
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Bimolecular nucleophilic substitution reactions between triphenylphosphine and benzylic electrophiles have been examined in an ionic liquid to probe interactions with species along the reaction coordinate. Trends in the rate constant were found on both varying the leaving group and the electronic nature of the aromatic ring. In all the cases considered, interactions between the components of the ionic liquid and the transition state were shown to be more significant in determining reaction outcome than previously observed for this class of reaction. This demonstrates the importance of considering interactions of the ionic liquid components with all species along the reaction coordinate when investigating the origin of ionic liquid solvent effects, along with how such effects might be exploited.
- Schaffarczyk McHale, Karin S.,Haines, Ronald S.,Harper, Jason B.
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p. 1162 - 1168
(2019/01/04)
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- Development of Tetrachlorophthalimides as Liver X Receptor β (LXRβ)-Selective Agonists
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Liver X receptor (LXR) agonists are candidates for the treatment of atherosclerosis via induction of ABCA1 (ATP-binding cassette A1) gene expression, which contributes to reverse cholesterol transport (RCT) and to cholesterol efflux from the liver and intestine. However, LXR agonists also induce genes involved in lipogenesis, such as SREBP-1c (sterol regulatory binding element protein 1c) and FAS (fatty acid synthase), thereby causing an undesirable increase in plasma and hepatic triglyceride (TG) levels. Recent studies indicate that LXRα contributes to lipogenesis in liver, and selective LXRβ activation improves RCT in mice. Therefore, LXRβ-selective agonists are promising candidates to improve atherosclerosis without increasing plasma or hepatic TG levels. However, the ligand-binding domains in the two LXR isoforms α/β share high sequence identity, and few LXR ligands show subtype selectivity. In this study we identified a tetrachlorophthalimide analogue as an LXRβ-selective agonist. Structural development led to (E)-4,5,6,7-tetrachloro-2-(2-styrylphenyl)isoindoline-1,3-dione (24 a), which shows potent and selective LXRβ agonistic activity in reporter gene assays. In binding assays, compound 24 a bound to LXRβ preferentially over LXRα. It also induced the expression of ABCA1 mRNA but not SREBP-1c mRNA in cells. Compound 24 a appears to be a promising lead compound for therapeutic agents to treat atherosclerosis without the side effects induced by LXRα/β dual agonists.
- Nomura, Sayaka,Endo-Umeda, Kaori,Makishima, Makoto,Hashimoto, Yuichi,Ishikawa, Minoru
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p. 2347 - 2360
(2016/10/25)
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- Benzofuran compound, preparation method and applications thereof
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The present invention provides a benzofuran compound, a preparation method and applications thereof, wherein the structure is represented by a general formula (I-1) or (I-2), R1, R3 and R4 are any one selected from hydrogen, C1-C5 straight or branched cha
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Paragraph 0047; 0048; 0049
(2016/10/08)
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- Benzofuran compounds intermediates, and preparation method and application thereof
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The invention provides a kind of benzofuran compounds intermediates, and a preparation method and application thereof, and the structure of the intermediates is shown as a general formula (I) in the specification. In the general formula (I), R1 and R3 are
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Paragraph 0048-0050
(2016/12/01)
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- Styrylphenylphthalimides as Novel Transrepression-Selective Liver X Receptor (LXR) Modulators
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Anti-inflammatory effects of liver X receptor (LXR) ligands are thought to be largely due to LXR-mediated transrepression, whereas side effects are caused by activation of LXR-responsive gene expression (transactivation). Therefore, selective LXR modulators that preferentially exhibit transrepression activity should exhibit anti-inflammatory properties with fewer side effects. Here, we synthesized a series of styrylphenylphthalimide analogues and evaluated their structure-activity relationships focusing on LXRs-transactivating-agonistic/antagonistic activities and transrepressional activity. Among the compounds examined, 17l showed potent LXR-transrepressional activity with high selectivity over transactivating activity and did not show characteristic side effects of LXR-transactivating agonists in cells. This representative compound, 17l, was confirmed to have LXR-dependent transrepressional activity and to bind directly to LXRβ. Compound 17l should be useful not only as a chemical tool for studying the biological functions of LXRs transrepression but also as a candidate for a safer agent to treat inflammatory diseases.
- Nomura, Sayaka,Endo-Umeda, Kaori,Aoyama, Atsushi,Makishima, Makoto,Hashimoto, Yuichi,Ishikawa, Minoru
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supporting information
p. 902 - 907
(2015/08/24)
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- Oxidative cyclizations, the synthesis of aryl-substituted c-glycosides, and the role of the second electron transfer step
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Anodic oxidation reactions have been used to synthesize aryl- and biaryl-substituted C-glycosides. The reactions take advantage of the tendency for alcohol nucleophiles to trap nonpolar radical cations. The addition of the alcohol to the radical cation appears to be reversible, and the success of the cyclizations is dependent on the ease with which the resulting benzylic radical is oxidized.
- Smith, Jake A.,Moeller, Kevin D.
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supporting information
p. 5818 - 5821
(2013/12/04)
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- Syntheses of p-terphenyls and 11,12-dihydroindeno[2,1-a]fluorene by one-pot benzannulation of Diels-Alder reactions of trans-1,2-dichloroethene and dienes
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A series of substituted p-terphenyls and 11,12-dihydroindeno[2,1-a]fluorene were successfully synthesized by one-pot benzannulation of Diels-Alder reaction with 1,2-dichloroethene as an acetylene equivalent dienophile. Two chlorine atoms could be good leaving groups to easily undergo subsequent elimination reactions of Diels-Alder products at a high temperature.
- Ho, Jinn-Hsuan,Lin, Yu-Chen,Chou, Li-Ting,Chen, Ying-Zhe,Liu, Wei-Qi,Chuang, Chao-Li
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supporting information
p. 1991 - 1993
(2013/04/10)
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- Synthesis and structure-activity analysis of new phosphonium salts with potent activity against African trypanosomes
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A series of 73 bisphosphonium salts and 10 monophosphonium salt derivatives were synthesized and tested in vitro against several wild type and resistant lines of Trypanosoma brucei (T. b. rhodesiense STIB900, T. b. brucei strain 427, TbAT1-KO, and TbB48). More than half of the compounds tested showed a submicromolar EC50 against these parasites. The compounds did not display any cross-resistance to existing diamidine therapies, such as pentamidine. In most cases, the compounds displayed a good selectivity index versus human cell lines. None of the known T. b. brucei drug transporters were required for trypanocidal activity, although some of the bisphosphonium compounds inhibited the low affinity pentamidine transporter. It was found that phosphonium drugs act slowly to clear a trypanosome population but that only a short exposure time is needed for irreversible damage to the cells. A comparative molecular field analysis model (CoMFA) was generated to gain insights into the SAR of this class of compounds, identifying key features for trypanocidal activity.
- Taladriz, Andrea,Healy, Alan,Flores Pérez, Eddysson J.,Herrero García, Vanessa,Ríos Martínez, Carlos,Alkhaldi, Abdulsalam A. M.,Eze, Anthonius A.,Kaiser, Marcel,De Koning, Harry P.,Chana, Antonio,Dardonville, Christophe
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supporting information; experimental part
p. 2606 - 2622
(2012/06/01)
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- Novel (E)-5-styryl-2,2′-bithiophene derivatives as ligands for β-amyloid plaques
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In continuation of our investigation on the bithiophene structure as potential β-amyloid probes, a series of (E)-5-styryl-2,2′-bithiophene (SBTP) derivatives was designed and synthesized. In vitro binding showed that all of them displayed high binding affinities to Aβ1-42 aggregates (Ki = 0.10-41.05 nM). Moreover, two radio-iodinated probes, [125I]-(E)-5-(4-iodostyryl)-2,2′-bithiophene ([ 125I]8) and [125I]-(E)-5-iodo-5′-(4-methoxystyryl)- 2,2′-bithiophene ([125I]31) were prepared. Both of them displayed specific labeling of Aβ plaques in the brain sections of AD model mice with low background. In vivo biodistribution in normal mice indicated that [125I]8 exhibited high initial brain uptake (2.11% ID/g at 2 min) and rapid clearance (0.41% ID/g at 30 min). These preliminary results suggest that SBTP derivatives may be served as novel β-amyloid imaging probes.
- Cui, Mengchao,Li, Zijing,Tang, Ruikun,Jia, Hongmei,Liu, Boli
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experimental part
p. 2908 - 2916
(2011/07/08)
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- Non-competitive and selective dipeptidyl peptidase IV inhibitors with phenethylphenylphthalimide skeleton derived from thalidomide-related α-glucosidase inhibitors and liver X receptor antagonists
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Novel dipeptidyl peptidase IV (DPP-IV) inhibitors with a phenethylphenylphthalimide skeleton were prepared based on α-glucosidase inhibitors and liver X receptor (LXR) antagonists derived from thalidomide. Representative compounds showed non-competitive i
- Motoshima, Kazunori,Sugita, Kazuyuki,Hashimoto, Yuichi,Ishikawa, Minoru
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supporting information; experimental part
p. 3041 - 3045
(2011/06/24)
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- Synthesis and biological evaluation of some stilbene-based analogues
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The phytoalexin 3,5,40-trihydroxy-trans-stilbene (resveratrol) has attracted considerable attention from biologists and chemists due to its diverse biological properties. Owing to the biological importance of this compound, we have synthesized new stilbene-based analogues by using substituted benzyl chlorides and substituted aldehydes in a two-step reaction and evaluated their in vitro antioxidant, antibacterial and antifungal potential. Most of the compounds displayed moderate to significant radical scavenging activity. (E)-1-(3,4-difluorophenyl)-2-(4-fluorophenyl) ethene (4c) showed nearer equipotent antibacterial activity against Staphylococcus aureus. (E)-1,2-bis (4-fluorophenyl)ethene (4a), (E)-1-(3-fluorophenyl)-2-(4-fluorophenyl)ethene (4b), (E)-1-(2,4-dichlorophenyl)-2-(3, 4-dichlorophenyl)ethene (4f), (E)-1-(2,4-dichlorophenyl)-2-(3-chlorophenyl)ethene (4g), (E)-1-(2,4- dichlorophenyl)-2-(4-fluorophenyl)ethene (4j) (E)-1-(4-fluorophenyl)-2-(3- chlorophenyl)ethene (4l) and (E)-1-(4-chlorophenyl)-2-(4-fluorophenyl)ethene (4n) inhibited the growth of Penicillium chrysogenum. Springer Science+Business Media, LLC 2010.
- Karki, Subhas S.,Bhutle, Santosh R.,Pedgaonkar, Ganesh S.,Zubaidha,Shaikh, Rizwan M.,Rajput, Chitra G.,Shendarkar, Girish S.
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experimental part
p. 1158 - 1163
(2012/05/05)
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- Synthesis and biological evaluation of some stilbene derivatives
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Several trans and cis stilbenes with substitution n the olefinic bridge were synthesized and characterized by IR, NMR and mass spectroscopy in an effort to obtain ubstances that could be more readily formulated. All the synthesized compounds were screened against Molt4/C8, CEM and L1210 cell lines. None of these compounds were ndowed with pronounced cytostatic activity. However,Schiff derivatives emerged as cytostatic agents (IC50: 0.77-10 μg/ml) that deserve further investigation. Springer Science+Business Media, LLC 2010.
- Karki, Subhas Somalingappa,Bhutle, Santosh Ramarao,Sahoo, Subhas,Reddy, Ratnakar,Balzarini, Jan,De Clercq, Erik,Darji, Satyanarayana Y.
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experimental part
p. 1349 - 1356
(2012/05/05)
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- VO(acac)2-catalyzed oxidative coupling reactions of phosphonium salts
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A novel eco-safer protocol for the preparation of symmetric or unsymmetric olefins directly from phosphonium salts under oxygen atmosphere in the presence of VO(acac)2 (1.0 mol%) was developed.
- Shi, Min,Xu, Bo
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p. 294 - 297
(2007/10/03)
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- Flash vacuum pyrolysis of stabilised phosphorus ylides. Part 16. Model studies for the construction of conjugated polymers
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Reaction of a range of bis(ylides) with acid chlorides has been used to prepare the bis(oxoylides) 11-15. Similarly a range of simple ylides react with bis(acid chlorides) to give bis(oxoylides) 19-27 with the isomeric structure. Flash vacuum pyrolysis (FVP) of one example of the first type results in extrusion of Ph3P rather than the expected Ph3PO while six examples of the second type do extrude Ph3PO upon FVP at 500 °C to afford the bis(alkynes) 28. Examples of the corresponding bis(tributylphosphonium ylides) have also been prepared but attempts to construct a tetrakis(oxoylide) 31 using a stepwise approach were unsuccessful. Fully assigned 13C NMR spectra are presented for six of the bis(oxoylides).
- Aitken, R. Alan,Drysdale, Martin J.,Hill, Lawrence,Lumbard, Keith W.,Maccallum, James R.,Seth, Shirley
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p. 11039 - 11050
(2007/10/03)
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- Synthesis and x-ray analysis of new [5]helicenes - HMO calculations on the photocyclization of the stilbene precursors
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The syntheses of the new pentahelicenes 5, 11, 17, 21, and 28 with various substituents are described. In the case of 2,13-dicyano-[5]helicene (11) optical resolution was achieved by HPLC using a column packed with γ- cyclodextrin. However, the enantiomers racemized within a few hours. On the other hand, the enantiomers of 28 turned out to be stable after separation on triacetylcellulose using MPLC. The crystal structures of 11, 17, and 21 were solved and indicated the typical distortions which are expected for helicenes. The model of the sum of free valence numbers was applied in order to rationalize the reactivity pattern of the photochemical phenanthrene cyclization.
- Stammel, Christian,Froehlich, Roland,Wolff, Christian,Wenck, Hans,De Meijere, Armin,Mattay, Jochen
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p. 1709 - 1718
(2007/10/03)
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- Synthesis, molecular modeling, and K+ channel-blocking activity of dequalinium analogues having semirigid linkers
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Dequalinium [1,1'-(decane-l,10-diyl)bis(2-methyl-4-aminoquinolinium)] is an effective blocker of the small conductance Ca2+activated K+ channel. It has been shown that the number of methylene groups in the alkyl chain linking the two quinolinium rings of this type of molecule is not critical for activity. To further investigate the role of the linker, analogues of dequalinium have been synthesized, in which the alkyl chain has been replaced by CH2XCH2 where X is a rigid or semirigid group containing aromatic rings. The compounds have been tested for blockade of the slow after- hyperpolarization on rat sympathetic neurons. The most potent compounds have X = phenanthryl, fluorenyl, cis-stilbene, and C6H4(CH2)(n)C6H4 where n = 0-4. The conformational preferences of the compounds were investigated using the XED/COSMIC molecular modeling system. Although there is some dependence of the potency of the analogue on the conformational properties of the linker (X), overall, X groups having substantial structural differences are tolerated. It seems that X provides a support for the two quinolinium groups and does not interact with the channel directly. The intramolecular separation between the quinolinium rings, which is provided by rigid groups X, is not critical for activity; this may be attributed to the residual conformational mobility of the heterocycles and to the extensive delocalization of the positive charge. These two factors may permit favorable contacts between the quinolinium groups and the channel over a range of intramolecular separations.
- Rosa, Joaquin Campos,Galanakis, Dimitrios,Ganellin, C. Robin,Dunn, Philip M.
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p. 4247 - 4254
(2007/10/03)
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- Photolysis of (Arylmethyl)triphenylphosphonium Salts. Substituent, Counterion, and Solvent Effects on Reaction Products
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Quaternary (arylmethyl)phosphonium salts of the general formula ArCH2-PR3(+)Y(-) (Ar = substituted phenyl or 1-naphthyl; R = phenyl, ferrocenyl, or butyl; Y(-) = BF4(-) or halide) have been photolyzed in acetonitrile or in methanol.Photolysis involved the cleavage of the P-CH2 bond and the products derived from both, the arylmethyl radical and the carbocation, were formed.The proportion of the radical- and carbocation-derived products was determined as a function of substituents in group Ar, of groups R, counterions Y(-), and the solvent.For the nonoxidizable counterion (BF4(-), the proposed mechanism of the reaction involves initial homolysis, followed by the escape of the radical products from a solvent cage, or by the electron transfer from carbon to phosphorus, yielding the corresponding arylmethyl carbocation.The latter can either react with the solvent to form the observed carbocation-derived product or can undergo recombination with the tertiary phosphine formed to yield the starting phosphonium ion.Some indication of the "inverted substituent effect" resulting from the inhibition of single electron transfer from an easily oxidized radical was obtained.For the oxidizable counterions (halides), an additional pathway is suggested, that involves electron transfer from the anion, yielding the arylmethyl radical and the phosphine, thus decreasing the ionic/radical products ratio.
- Imrie, C.,Modro, T. A.,Rohwer, E. R.,Wagener, C. C. P.
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p. 5643 - 5649
(2007/10/02)
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- Electron Demand in the Transition State of the Cyclopropylidene to Allene Ring Opening
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The electronic structure of the transition state for the cyclopropylidene to allene conversion has been probed.The methodology involved the relative rates of ring opening vs trapping by MeOH for a series of variously substituted 2,3-diarylcyclopropylidenes.With the assumption that the rate of trapping was unaffected by substituents, a Hammett correlation was constructed.The negative value (-0.72) for ρ indicated that the carbenic center attracts electron density in the ring-opening transition state, much like the cyclopropyl cation to allyl cation transition state.Temperature-dependent studies showed that the observed preference for ring opening was driven by entropy factors.Also, using reasonable estimates for the close to diffusion-controlled trapping activation enthalpies, the derived enthalpies for ring opening were in close agreement with the best theoretical values.
- Warner, Philip,Sutherland, Robert
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p. 6294 - 6300
(2007/10/02)
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- An Unusual Fluorine Atom Rearrangement in the Photocyclization of 1-Fluorohelicenes
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Oxidative photocyclization of 1-fluorohelicene and two of its chlorine-substituted derivatives leads to the formation of 8-fluorobenzoperylenes through an unprecedented inter-ring fluorine atom migration; photoelimination of HF to give benzoperylenes also occurs as a competing process.The rearrangement pathway predominates when the irradiation is carried out at 0 deg C in air-saturated benzene solution containing 10 -3 M iodine; the elimination pathway predominates at higher temperatures or in the absence of either oxygen or iodine.The rearrangement isrationalized by postulating a triplet-state photocyclization to give a dihydrobenzoperylene intermediate, followed by abstraction of the tertiary hydrogen atom from that intermediate to give a radical that subsequently undergoes a fluorine atom shift by an SNi'mechanism.
- Mallory, Frank B.,Mallory, Clelia W.
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p. 526 - 532
(2007/10/02)
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- MERCAPTOACYL DERIVATIVES OF VARIOUS 4-SUBSTITUTED PROLINES
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This invention is directed to compounds of the formula STR1 and various intermediates therefore. The final products possess useful hypotensive activity.
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- Synthesis and Photocylization of some 4-(5)Arylethenylimidazoles
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The synthesis of eleven 4-(5)arylethenylimidazoles and their separation into cis and trans isomers is described.Ir, uv, nmr, and mass spectrometric data of the compounds are given.The photocyclization of the unsubstituted and p-substituted compounds is reported.
- Lindberg, Gerd,Stensioe, Karl-Erland,Wahlberg, Kerstin
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p. 679 - 683
(2007/10/02)
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