- Hydrogen-bonded bent-core blue phase liquid crystal complexes containing various molar ratios of proton acceptors and donors
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Various hydrogen-bonded (H-bonded) bent-core liquid crystal complexes consisting of pyridyl and benzoic acid derivatives were synthesized and compared with their covalent analogues in this study. The molar ratios of pyridyl and benzoic acid derivatives could be tuned to form various H-bonded liquid crystal (LC) diads (with 1:1 molar ratio of H-acceptors T and H-donors D) and complexes (with different molar ratios of T and D). By insertion of H-bonds into different positions of bent-core supramolecules, the mesophasic properties of H-bonded bent-core LC complexes were optimized, which could facilitate the most suitable LC components and compositions to be utilized in H-bonded blue phase (BP) LC complexes. In BPLC complexes, the molar ratios, alkyl chain lengths, the lateral fluoro-substitution and the chiral center of H-bonded bent-core supramolecules would affect the temperature ranges of BPs. Accordingly, H-bonded bent-core complex PIIIC9/AIIF? (3/7 mol mol-1) displayed the widest BPI range of ΔTBPI = 12.0 °C at the correspondent H-acceptor T = PIIIC9 and H-donor D = AIIF?. Since the covalent-bonded bent-core mixture only had narrow ranges of BPIII, we could summarize that the introduction of H-bonds into the bent-core center effectively stabilizes the BPs and easier induces the BPI.
- Han, Chun-Chieh,Chou, Yu-Chaing,Chen, San-Yuan,Lin, Hong-Cheu
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p. 32319 - 32327
(2016/04/26)
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- Synthesis of fluorosubstituted three ring esters and their dielectric properties
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Laterally substituted by fluorine atoms 4-cyanophenyl 4-(4- pentylbenzoyloxy)-benzoates have been prepared and their phase transition temperatures, enthalpies and dielectric properties upon frequency were evaluated. The novel compounds exhibit a broad range of nematic mesophase, large positive dielectric anisotropy changing sign at low frequency. They are convenient components of LC mixtures for dual frequency addressing devices. Copyright Taylor & Francis Group, LLC.
- Ziobro, Dorota,Dziaduszek, Jerzy,Filipowicz, Marek,Dabrowski, Roman,Czu, Joanna,Urban, Stanislaw
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experimental part
p. 258 - 271
(2012/08/08)
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- Bioavailable diacylhydrazine ligands for modulating the expression of exogenous genes via an ecdysone receptor complex
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The present invention relates to non-steroidal ligands for use in nuclear receptor-based inducible gene expression system, and a method to modulate exogenous gene expression in which an ecdysone receptor complex comprising: a DNA binding domain; a ligand binding domain; a transactivation domain; and a ligand is contacted with a DNA construct comprising: the exogenous gene and a response element; wherein the exogenous gene is under the control of the response element and binding of the DNA binding domain to the response element in the presence of the ligand results in activation or suppression of the gene.
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Page/Page column 30
(2008/06/13)
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- Converting core compounds into building blocks: The concept of regiochemically exhaustive functionalization
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In a model study, 3-fluorophenol and 3-fluoropyridine were converted into the each time four possible carboxylic acids by passing through the corresponding organometallic intermediates. As an attempt to generalize the findings reveals, a restricted set of principles and methods suffices to cope with all standard scenarios. The most valuable and versatile tools for the regiochemically exhaustive functionalization of a great variety of substrate patterns are the optionally site-selective metalation (either by reagent/substrate matching or by peripheral coordination control), the use of activating or congesting protective groups and the basicity gradient-driven heavy halogen migration (followed by halogen/metal permutation). Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
- Marzi, Elena,Bobbio, Carla,Cottet, Fabrice,Schlosser, Manfred
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p. 2116 - 2123
(2007/10/03)
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- Regio-selective hydroxysubstitution of fluorobenzoic acid derivatives: Facile synthesis of fluorosalicylic acid derivatives
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Ortho-substituted fluorine in 2,4-difluorobenzoic acid was found to be regio-selectively replaced to hydroxide by solid sodium hydroxide in 1,3-dimethyl-2-imidazolidinone, to afford 4-fluoro-2-hydroxybenzoic acid in high yield. Several multi-fluoro-substi
- Umezu, Kazuto,Tabuchi, Fumiya,Kimura, Yoshikazu
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- Compounds having activity as inhibitors of cytochrome P450RAI
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Compounds having Formula 2 wherein the symbols have the meaning defined in the specification are inhibitors of the cytochrome P450RAI (retinoic acid inducible) enzyme, and are used for treating diseases responsive to treatment by retinoids.
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Page column 25
(2010/01/31)
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- Liquid crystal materials, mixtures and devices
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Liquid crystal compounds of formula I may be used by themselves or they may be mixed with other liquid crystal compounds to give useful liquid crystal mixtures which may then be used in liquid crystal devices. The materials exhibit smectic mesophases and may therefore be used in ferroelectric, ferrielectric, antiferroelectric, themochromic and electroclinic devices. They may also be used as long pitch materials.
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- Benzopyran derivatives having leukotriene-antagonistic action
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The present invention relates to novel 4-oxo-4H-1-benzopyran compounds containing benzyloxymethyl, 3-phenylpropyl, or other araliphatic substituents in their 8-position. These compounds show a leukotriene-antagonistic activity. The compounds are characterized by good oral adsorption. The compounds of the present invention may be used as anti-inflammatory and antiallergic medicaments, and in the treatment of cardiovascular diseases.
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- Fluorinated linkers for monitoring solid-phase synthesis using gel- phase 19F NMR spectroscopy
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Three fluorinated linkers which are analogues of linkers commonly used in solid-phase peptide synthesis have been prepared. Using 19F NMR spectroscopy, the fluorine atom of the linker allowed monitoring of several transformations in the solid-phase synthesis of a peptoid having a coumarin moiety. Especially, attachment of the linker to the solid phase, coupling of the first building block to the linker and cleavage of the product were efficiently monitored and optimised.
- Svensson, Anette,Bergquist, Karl-Erik,Fex, Tomas,Kihlberg, Jan
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p. 7193 - 7196
(2007/10/03)
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- The Synthesis and Liquid Crystal Properties of Some Laterally Fluorinated trans-Cyclohexane-1-carboxylate and Benzoate Esters
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A large number of laterally fluorinated 4-n-alkyl- and -alkoxy-phenyl 4'-n-alkyl- and -alkoxy-bezoates and 4-n-alkylphenyl trans-4'-n-alkyl- and -alkoxy-cyclohexane-1-carboxylates were synthesised.In these compounds, the lateral fluoro-substituent was situated in either the phenol or the carboxylic acid moiety of the molecules for the benzoate esters, but only in the phenol moiety for the trans-cyclohexane-1-carboxylate esters.The nematic thermal stabilities for the fluorophenyl bezoate and trans-cyclohexane-1-carboxylate esters and the fluorobenzoate esters were compared with those for the corresponding non-fluorinated analogues.A nematic thermal efficiency order was derived for the 4-n-alkyl-fluorophenyl 4-n-alkylbezoate and trans-4-n-alkylcyclohexane-1-carboxylate esters, but only in the case of the latter esters, which were extensively examined, was the smectic tendency of the system investigated.Explanations are given for the observed nematic and smectic thermal stabilities of the titled esters, and some of their physical properties are discussed.
- Gray, G. W.,Hogg, C.,Lacey, D.
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