220568-93-4Relevant articles and documents
Dynamic Molecular Invasion into a Multiply Interlocked Catenane
Yamada, Yasuyuki,Itoh, Ryohei,Ogino, Sayaka,Kato, Tatsuhisa,Tanaka, Kentaro
, p. 14124 - 14129 (2017)
A multiply interlocked catenane with a novel molecular topology was synthesized; a phthalocyanine bearing four peripheral crown ethers was quadruply interlocked with a cofacial porphyrin dimer bridged with four alkylammonium chains. The supramolecular conjugate has two nanospaces surrounded by a porphyrin, a phthalocyanine, and four alkyl chains to accommodate guest molecules. Because the phthalocyanine can move along the alkyl chains, it acts as an adjustable wall, thus permitting the invasion of large molecules into the nanospaces without spoiling the affinity of the association. The dynamic molecular invasion allowed the intercalation of dianionic porphyrins into both nanospaces with high affinity. A photometric titration experiment revealed the two-step inclusion phenomenon. The multiply interlocked catenane complexed with three Cu2+ ions, and the spin–spin interaction was switched off by the intercalation of dianionic porphyrins.
A quantitative assessment of chemical perturbations in thermotropic cyanobiphenyls
Guerra, Sebastiano,Dutronc, Thibault,Terazzi, Emmanuel,Guénée, Laure,Piguet, Claude
, p. 14479 - 14494 (2016/06/09)
Chemical programming of the temperature domains of existence of liquid crystals is greatly desired by both academic workers and industrial partners. This contribution proposes to combine empirical approaches, which rely on systematic chemical substitution
Monolayer to Interdigitated Partial Bilayer Smectic C Transition in Thiophene-Based Spacer Mesogens: X-ray Diffraction and 13C Nuclear Magnetic Resonance Studies
Kesava Reddy,Varathan,Lobo, Nitin P.,Roy, Arun,Narasimhaswamy,Ramanathan
, p. 10831 - 10842 (2015/10/12)
Mesophase organization of molecules built with thiophene at the center and linked via flexible spacers to rigid side arm core units and terminal alkoxy chains has been investigated. Thirty homologues realized by varying the span of the spacers as well as the length of the terminal chains have been studied. In addition to the enantiotropic nematic phase observed for all the mesogens, the increase of the spacer as well as the terminal chain lengths resulted in the smectic C phase. The molecular organization in the smectic phase as investigated by temperature dependent X-ray diffraction measurements revealed an interesting behavior that depended on the length of the spacer vis-a-vis the length of the terminal chain. Thus, a tilted interdigitated partial bilayer organization was observed for molecules with a shorter spacer length, while a tilted monolayer arrangement was observed for those with a longer spacer length. High-resolution solid state 13C NMR studies carried out for representative mesogens indicated a U-shape for all the molecules, indicating that intermolecular interactions and molecular dynamics rather than molecular shape are responsible for the observed behavior. Models for the mesophase organization have been considered and the results understood in terms of segregation of incompatible parts of the mesogens combined with steric frustration leading to the observed lamellar order.
BIFUNCTIONAL POLYMERIZABLE COMPOUND, POLYMERIZABLE LIQUID CRYSTAL COMPOSITION, AND ORIENTED FILM
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Page/Page column 29-30, (2009/07/10)
Disclosed is a bifunctional polymerizable compound represented by the formula [1]. Also disclosed is a polymerizable liquid crystal composition comprising at least one bifunctional polymerizable compound represented by the formula [1] and a polymerizable liquid crystal compound. The bifunctional polymerizable compound has a high polymerizability. When added to a polymerizable liquid crystal compound to prepare a polymerizable liquid crystal composition, the bifunctional polymerizable compound enables to remarkably improve the thermal stability of a polymer produced from the composition. The polymerizable liquid crystal composition containing the bifunctional polymerizable compound has a low crystallization temperature and shows a stable liquid-crystallinity under ordinary environment. wherein X1, X2 and X3 independently represent a single bond or a benzene ring; Y represents -O- or a single bond; M represents a lactone ring or an acrylate group; and n represents an integer of 4 to 10.
Synthesis and biological evaluation of a series of flavone derivatives as potential radioligands for imaging the multidrug resistance-associated protein 1 (ABCC1/MRP1)
Mavel, Sylvie,Dikic, Branko,Palakas, Somchit,Emond, Patrick,Greguric, Ivan,De Gracia, Adrienne Gomez,Mattner, Filomena,Garrigos, Manuel,Guilloteau, Denis,Katsifis, Andrew
, p. 1599 - 1607 (2007/10/03)
Multidrug resistance (MDR) is one of the major problems affecting the treatment of cancer. In vivo visualization and quantification of MDR proteins would be of great value to better select the therapeutic strategy. Six flavone-based compounds were synthesized and evaluated for their cytotoxic activity and MDR-reversing capacity using hMRP1 or hMDR1 overexpressing cell lines for in vitro assays. All the flavone derivatives were highly selective for hMRP1-expressing cell lines. These derivatives each used at 4 μM (a non-cytotoxic concentration) enhance significantly the sensitivity of hMRP1-mediated MDR cell line toward doxorubicin toxicity. Their MDR-reversing capacity suggests that, in particular, the 4′-fluoroalkyloxy and 4′-iodo apigenin derivatives are potential new radiopharmaceuticals to visualize in vivo MRP1-mediated MDR phenomenon by PET or SPECT.
