- 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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- A triphenylamine as a fluorophore and maleimide as a bonding group selective turn-on fluorescent imaging probe for thiols
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With the biological importance of biothiols, the development of probes for thiols has been an active research area in recent years. Here, we report a novel thiol-reactive fluorescent probe based on Michael addition reaction for selectively detecting thiol
- Liu, Tao,Huo, Fangjun,Yin, Caixia,Li, Jianfang,Chao, Jianbin,Zhang, Yongbin
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p. 209 - 214
(2016/02/27)
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- Substituted diphenyl derivatives
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Triazene-substituted diphenyl derivatives are suitable as chemotherapeutic agents for treating carcinomas in humans and animals.
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Paragraph 0241; 0242
(2014/02/15)
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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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- Target directed chemotherapy of tumours of the sexual organs
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The invention relates to dialkyltriazene-bearing estrogens and anti-estrogens that are suited for use as chemotherapeutic drugs for treating carcinomas of the sexual organs of humans and animals.
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- TARGET-ORIENTED CHEMOTHERAPY FOR TREATING TUMORS OF THE SEXUAL ORGANS
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The invention relates to dialkyltriazene-supporting estrogens and antiestrogens that are suited for use as chemotherapeutic drugs for treating carcinomas of the sexual organs of humans and animals.
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Page/Page column 28
(2010/02/09)
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- Experimental evidence for multiple oxidation pathways in the (salen)Mn-catalyzed epoxidation of alkenes
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The substrate electronic effects on the selectivity in the catalytic epoxidation of para-substituted cis stilbenes 2a-i were investigated by using (R,R)-[N,N′-bis(3,5-di-tBu-salicylidene)-1,2-cyclohexanediamine] manganese(III) chloride 1 in benzene as the catalyst with iodosobenzene as the terminal oxidant. A Hammett study of the selectivity results reveals a stronger electrophilic character than previously assumed in the (salen)Mn-catalyzed reaction. In general, the best correlations with the experimental values were obtained by using the Hammett σ+ values, which gave ρ = -1.37 for the rate of cisepoxide formation and ρ = -0.43 for the rate of the stepwise process leading to the corresponding trans product. The reaction involves two separate pathways as indicated also by the competitive breakdown of the intermediate on the path to trans epoxide for methoxy-substituted substrates. The asynchronicity in the concerted pathway leading to cis epoxide is apparent for 4-methoxy-4′-nitrostilbene, which yields cis epoxide with 75% ee entirely as a result of electronic effects.
- Linde, Christian,Koliai, Nordine,Norrby, Per-Ola,Akermark, Bjoern
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p. 2568 - 2573
(2007/10/03)
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- Syntheses of 2-(2-arylethyl)-1-methylimidazoles
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2-(2-Arylethyl)-1-methylimidazoles 3 could be prepared by different methods. The best method was the Wittig reaction of aryltriphenylphosphonium chloride 8 with 2-formyl-1-methylimidazole to give compound 6. Reduction of compound 6 with Raney nickel gave compound 3.
- Shafiee,Morteza-Semnani,Foroumadi
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p. 671 - 673
(2007/10/03)
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- Preparation of (E)-2-Hxdroxy-4'-Substituted Stilbenes
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Sixteen (E)-2-hydroxy-4'-substituted stilbenes have been prepared by the Wittig reaction.Direct coupling of the appropriate p-substituted benzylidenetriphenylphosphoranes with salicylaldehyde afforded the (E)-stilbenols (2) 4'-R = H(2a), Me(2b), But(2c), Ph(2d), CN(2e), NO2(2i), OMe(2k), F(2n), Cl(2o), and Br(2p).Alternatively, the Wittig reaction of o-methoxymethoxybenzylidenetriphenylphosphorane with various p-substituted benzaldehydes gave the (E)-methoxymethylstilbenols (4) which upon acidic cleavage furnished the corresponding stilbenols (2) 4'-R = CN(2e), CO2Me(2f), NMe2(2h), OH(2j), OAc(2m), and I(2q).The symmetrical (E)-2,2'-dihydroxystilbene was obtained in an analogous fashion.Reduction of nitrostilbenol (2i) yielded the corresponding aminostilbenol (2g).
- Mylona, Anastasia,Nikokavouras, John,Takakis, Ioannis M.
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p. 3514 - 3530
(2007/10/02)
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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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