92278-49-4Relevant academic research and scientific papers
Unconventional Langmuir-Blodgett films: Alignment of an optically nonlinear dye where the donor and π-electron bridge are hydrophobic and the acceptor is hydrophilic
Ashwell, Geoffrey J.,Maxwell, Alison A.,Green, Andrew
, p. 2192 - 2196 (2002)
The optically nonlinear dye, 5-{4-[2-(4-dibutylaminophenyl)vinyl]benzylidene}-2-(1-ethylpropyl)-5,6,7, 8-tetrahydroisoquinolinium bromide (1a), differs from other Langmuir-Blodgett (LB) film-forming materials. The molecule is amphiphilic and, therefore, may be aligned at the air-water interface but, instead of a conventional aliphatic tail, has an extended π-electron bridge. It forms non-centrosymmetric LB films which exhibit second-harmonic generation (SHG) and have a high second-order susceptibility: χ(2)zzz = 40 pm V-1 at 1.064 μm for a monolayer thickness of 1.8 nm and chromophore tilt angle of 55° from the substrate normal. The octadecyl sulfate salt (1b) also forms non-centrosymmetric films but with improved properties: χ(2)zzz = 90 pm V-1 at 1.064 μm for d = 2.4 nm and φ = 33°. Both films exhibit charge-transfer bands at 360 nm but with absorbance cut-off above 560 nm for 1a and 530 nm for 1b. The latter is fully transparent at the fundamental and harmonic wavelengths and its susceptibility is the highest to date for such a film. This results from an optimised packing arrangement, a conjugation enhanced molecular hyperpolarisability of β = 4.3 × 10-38 m4 V-1, and the proximity of the absorption band, albeit non-overlapping at 532 nm. The properties are compared with those of conventional long alkyl tailed materials (2 and 3) of the same chromophore.
Chemical Targeting of Voltage Sensitive Dyes to Specific Cells and Molecules in the Brain
Fiala, Tomas,Wang, Jihang,Dunn, Matthew,?ebej, Peter,Choi, Se Joon,Nwadibia, Ekeoma C.,Fialova, Eva,Martinez, Diana M.,Cheetham, Claire E.,Fogle, Keri J.,Palladino, Michael J.,Freyberg, Zachary,Sulzer, David,Sames, Dalibor
supporting information, p. 9285 - 9301 (2020/06/04)
Voltage sensitive fluorescent dyes (VSDs) are important tools for probing signal transduction in neurons and other excitable cells. The impact of these highly lipophilic sensors has, however, been limited due to the lack of cell-specific targeting methods in brain tissue or living animals. We address this key challenge by introducing a nongenetic molecular platform for cell- and molecule-specific targeting of synthetic VSDs in the brain. We employ a dextran polymer particle to overcome the inherent lipophilicity of VSDs by dynamic encapsulation and high-affinity ligands to target the construct to specific neuronal cells utilizing only native components of the neurotransmission machinery at physiological expression levels. Dichloropane, a monoamine transporter ligand, enables targeting of dense dopaminergic axons in the mouse striatum and sparse noradrenergic axons in the mouse cortex in acute brain slices. PFQX in conjunction with ligand-directed acyl imidazole chemistry enables covalent labeling of AMPA-type glutamate receptors in the same brain regions. Probe variants bearing either a classical electrochromic ANEP dye or state-of-the-art VoltageFluor-type dye respond to membrane potential changes in a similar manner to the parent dyes, as shown by whole-cell patch recording. We demonstrate the feasibility of optical voltage recording with our probes in brain tissue with one-photon and two-photon fluorescence microscopy and define the signal limits of optical voltage imaging with synthetic sensors under a low photon budget determined by the native expression levels of the target proteins. This work demonstrates the feasibility of a chemical targeting approach and expands the possibilities of cell-specific imaging and pharmacology.
Rhenium and technetium complexes that bind to amyloid-β plaques
Hayne, David J.,North, Andrea J.,Fodero-Tavoletti, Michelle,White, Jonathan M.,Hung, Lin W.,Rigopoulos, Angela,Mclean, Catriona A.,Adlard, Paul A.,Ackermann, Uwe,Tochon-Danguy, Henri,Villemagne, Victor L.,Barnham, Kevin J.,Donnelly, Paul S.
, p. 4933 - 4944 (2015/03/18)
Alzheimer's disease is associated with the presence of insoluble protein deposits in the brain called amyloid plaques. The major constituent of these deposits is aggregated amyloid-β peptide. Technetium-99m complexes that bind to amyloid-β plaques could p
Comparison between organic sensitizers containing stilbene and azo group as bridging unit for dye sensitized solar cells
Park, Se Woong,Namgoong, Jin Woong,Kwon, Il Keun,Kim, Jae Pil
, p. 7502 - 7507 (2014/12/10)
While azo dyes have been widely used in dye industry, the azo dyes have been seldom applied as sensitizers to dye sensitized solar cells. In this study, new metal-free organic sensitizers, ST and AZ, which are same structures except bridging units, were synthesized and evaluated. ST containing stilbene as bridging unit gave higher energy conversion efficiency than AZ containing azo group as bridging unit. As a result of density functional theory (DFT) calculations, ST displayed more localized frontier molecular orbitals at lowest unoccupied molecular orbital (LUMO) states than AZ.
N,N′-Dibutylbarbituric acid as an acceptor moiety in push-pull chromophores
Klikar, Milan,Bures, Filip,Pytela, Oldrich,Mikysek, Tomas,Padelkova, Zdenka,Barsella, Alberto,Dorkenoo, Kokou,Achelle, Sylvain
supporting information, p. 4230 - 4240 (2013/12/04)
Twelve novel D-π-A chromophores with the N,N′-dibutylbarbituric acid acceptor, the N,N-dimethylamino donor and a systematically extended π-linker were synthesized. The extent of intramolecular charge-transfer, structure-property relationships and nonlinear optical properties were further investigated by X-ray analysis, electrochemistry, UV/Vis absorption spectra, calculations and EFISH experiments.
Switching of emissive and NLO properties in push-pull chromophores with crescent PPV-like structures
Coluccini, Carmine,Sharma, Arvind K.,Caricato, Marco,Sironi, Angelo,Cariati, Elena,Righetto, Stefania,Tordin, Elisa,Botta, Chiara,Forni, Alessandra,Pasini, Dario
, p. 1666 - 1674 (2013/03/13)
We report on a series of novel homologous push-pull compounds, in which identical donor (a dimethylamino) and acceptor (a malonate ester) functionalities endcap crescent PPV fragments, bearing, respectively, 1, 2 and 3 p-phenylenevinylene units in direct linear conjugation (compounds 7-9). The three compounds exhibit striking differences in their linear and nonlinear optical properties. The shorter compound 7 exhibits aggregation-induced emission with a strong luminescence in the solid state (blue emission, photoluminescence quantum yield 38%), and it is nonemissive in solution; the more extended conjugated systems 8 and 9 show classical aggregation-caused quenching in the solid state, while high quantum yield photoluminescence (21 and 93% in toluene) is restored in diluted solutions, through mechanisms involving intramolecular charge transfer in the excited states. EFISH measurements in solutions demonstrate a strong solvent and concentration dependence. As rationalized with the aid of molecular modelling, compounds 8 and, more markedly, 9 aggregate in stable centrosymmetric dimers in solution.
AMYLOID BINDING AGENTS
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Page/Page column 38-39; 42-43, (2011/06/26)
There are provided compounds and methods for the detection of amyloids and treatment of diseases related to amyloids including Alzheimer?s disease and other related amyloid-based neurodegenerative diseases
π-Extended alkylidenecycloproparenes
Halton, Brian,Cooney, Mark J.
, p. 118 - 122 (2008/02/02)
Reaction of benzene-1,4-dicarboxaldehyde with anion 6 derived from 1,1-bis(trimethylsilyl)cyclopropa[b]naphthalene 1 gives 4-(methylidene-1H-cyclopropanaphthalenyl)benzaldehyde 7 as a minor product and 1,4-bis(methylidene-1H-cyclopropanaphthalenyl)benzene
