共查询到20条相似文献,搜索用时 15 毫秒
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Cheikh?L? Jean-Jacques?Aaron Václav?Kozmík Ji?í?Svoboda Jean-Claude?Brochon Li?Na 《Journal of fluorescence》2010,20(5):1037-1047
The synthesis, electrochemical and optical properties of three fluorescent substituted thieno[3,2-b][1]benzothiophenes (TBT)
derivatives, including 3-methoxythieno[3,2-b][1]benzothiophene (3-MeO-TBT), 2,3-dimethylthieno[3,2-b][1]benzothiophene (2,3-diMe-TBT),
and 6-methoxythieno[3,2-b][1]benzothiophene-2-carboxylate (6-MeO-TBT-2-COOMe), were investigated. The oxidation potential
values varied between 1.40 and 1.20 V/SCE according to the electronic substituent effect, and electropolymerization attempts,
performed in 0.1 M LiClO4 acetonitrile solution, led to the formation of very thin films of poly(3-MeO-TBT) and poly(2,3-di-Me-TBT). Electronic absorption
spectra, fluorescence excitation and emission spectra, fluorescence quantum yields (ΦF) , lifetimes (τF), and other photophysical parameters of the three new TBT derivatives were measured in DMSO solutions at room temperature.
For the methyl-and methoxy-substituted TBT derivatives, the fluorescence emission peak were slightly red shifted relative
to that of unsubstituted TBT (Δλem = 1–12 nm) whereas, in the case of 6-MeO-TBT-2-COOMe, a rather strong red-shift (Δλem = 73 nm) was attributed to the existence of a “push-pull” electronic interaction of the MeO and COOMe groups. All ΦF values were rather high, varying between 0.11 and 0.35, according to the substituent effect. Fluorescence decays were mono-exponential
and τF values were very short, ranging between 0.11 and 0.30 ns for the substituted TBT derivatives until study. 相似文献
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Hui-ding Xie Louisa A. Ho Michael S. Truelove Ben Corry Scott G. Stewart 《Journal of fluorescence》2010,20(5):1077-1085
In this paper we describe a semi-empirical quantum method for predicting the wavelength of maximum fluorescence excitation
and emission for several known and new maleimide derivatives. All new maleimides, containing a N-Benzyl attachment, were successfully synthesised via a tandem Suzuki reaction with aryl boronic acids containing either an electron donating, electron withdrawing functional
groups. Absorption and emission spectra calculated using the semi-empirical AM1 method with excited state ZINDO calculations
proved more reliable than either Hartree-Fock Configuration interaction or time dependent density functional methods. Calculated
absorption and emission wavelengths were compared with 26 experimental spectra from known or newly synthesised maleimides
and found to have provide reasonable predictions, with an average deviation of less the 6% for absorption maxima and less
than 4% for emission peaks. The described method provides a strong benchmark for the accuracy that can be expected from theoretical
predictions of fluorescence spectra. 相似文献
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A variety of contemporary analytical platforms, utilized in technical and biological applications, take advantage of labeling the objects of interest with fluorescent tracers-compounds that can be easily and sensitively detected. Here we describe the synthesis of new fluorescent quinoline and quinolone compounds, whose light emission can be conveniently tuned by simple structural modifications. Some of these compounds can be used as sensitizers for lanthanide emission in design of highly sensitive luminescent probes. In addition, we also describe simple efficient derivatization reactions that allow introduction of amine- or click-reactive cross-linking groups into the fluorophores. The reactivity of synthesized compounds was confirmed in reactions with low molecular weight nucleophiles, or alkynes, as well as with click-reactive DNA-oligonucleotide containing synthetically introduced alkyne groups. These reactive derivatives can be used for covalent attachment of the fluorophores to various biomolecules of interest including nucleic acids, proteins, living cells and small cellular metabolites. Obtained compounds are characterized using NMR, steady-state fluorescence spectroscopy as well as UV absorption spectroscopy. 相似文献
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Bobrov A. V. Kishalova M. V. Ksenofontov A. A. Usoltsev S. D. Marfin Yu. S. 《Journal of fluorescence》2021,31(6):1627-1635
This paper highlights advances made using the 4-bora-3a,4a-diaza-s-indacene (BODIPY) as a fluorophore in design and application of fluorescent sensors for microenvironment polarity. Sections of the paper cover broad analysis of a range of fluorescent indicators immobilized in ethyl- and methyl cellulose matrices. The present study demonstrates that BODIPY-based fluorescent materials could be successfully utilized for ratiometric detection of ethanol and acetone in gas phase. The achieved limit of detection value equals 0.02 mg/ml for acetone and 0.08 mg/ml for ethanol, whereas obtained sensoric materials are reusable without regeneration required.
相似文献9.
An aqueous mediated novel synthesis of substituted 2′amino-4′benzoyl-2′-methyl spiro[indole 3,5′-[1,3]oxathiolane]-2(1H)-ones (2a–f) was carried out from the reaction of spiro [indole-3,2′-oxiranes] (1a–f) with thioacetamide in the presence of LiBr as catalyst. The reaction was carried out under both microwaves and sonication and results were also compared with conventional method. In general, improvement in rate and yields observed when reaction was carried out under sonication as compared to microwave irradiation and conventional method. 相似文献
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Calix[4]arene forms elongated nanoporous microcrystals. The pores are linear nano-channels (1.7 nm diameter) arranged in a honeycomb network. The crystals luminesce at room temperature according to a variety of processes that include monomer fluorescence (lifetime of ca. 1.1 ns), dimer fluorescence (lifetime of ca. 5.4 ns), and monomer phosphorescence (lifetime of ca. 2 s). The dimers result from pi-orbital overlap of adjacent phenol groups from neighboring nano-channels, with C-C distances of ca. 4 A. 相似文献
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Amir Badshah Saleem Nawaz Muhammad Faizan Nazar Syed Sakhawat Shah Aurangzeb Hasan 《Journal of fluorescence》2010,20(5):1049-1059
An approach is demonstrated toward the synthesis of four novel cyclohexenone derivatives (CDs) via a convenient route of Michael addition of ethyl acetoacetate. The molecular structures of CDs were confirmed by means of
FT-IR, 1H NMR, EIMS, UV and also by X-ray single crystal structure analysis. CDs are strongly fluorescent compounds and their fluorescent
spectra exhibits intense violet fluorescence. To model the binding to biological membranes the behavior of CDs in micellar
solutions of a cationic surfactant, cetyltrimethylammonium bromide (CTAB) and an anionic surfactant, sodium dodecylsulfate
(SDS) has also been examined. The characteristics of partition and binding interactions of CDs with CTAB and SDS were investigated
by UV-Visible and fluorescence spectroscopic techniques. Higher values of all mentioned interactions in case of CTAB, compared
to SDS, indicate that there are greater interactions between the CDs and CTAB than with SDS. 相似文献
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Synthesis and Photophysics of Some Novel Imidazole Derivatives Used as Sensitive Fluorescent Chemisensors 总被引:1,自引:0,他引:1
Kanagarathinam Saravanan Natesan Srinivasan Venugopal Thanikachalam Jayaraman Jayabharathi 《Journal of fluorescence》2011,21(1):65-80
Some novel imidazole derivatives were developed for highly sensitive chemisensors for transition metal ions. Since these compounds are sensitive to different external stimulations such as UV irradiation, heat, increasing pressure and changing the environmental pH causing colour change and so they can be used as a ??multi-way?? optically switchable material. A prominent fluorescence enhancement was found in the presence of transition metal ions such as Hg2+, Pb2+ and Cu2+ and this was suggested to result from the suppression of radiationless transitions from the n-??* state in the chemisensors. The existence of C-H??.O intramolecular hydrogen bonding in dmphnpi is confirmed by the Natural Bond Orbital analysis (NBO). The Mulliken, NBO charge analysis and the HOMO-LUMO energies were also calculated. The electric dipole moment (??) and the first-hyperpolarisability (??) value of the investigated molecules have been studied both experimentally and theoretically which reveal that the synthesized molecules have microscopic non-linear optical (NLO) behaviour with non-zero values. Ground and excited state DFT calculation were carried out in order to find out dipole moment and energy. 相似文献
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以二硫化碳和金属钠为基础物质合成了四硫富瓦烯(TTF)锌的配合物(TTF)Zn(NBu4)2。利用该化合物与苯甲酰氯反应得到的稳定化合物C17H10O2S5在甲醇钠溶液中与2,3-二溴丙醇反应成功合成出目标化合物(一种新配体),其化学组成为C6H6OS5。利用IR谱、^1HNMR谱及元素分析对此化合物进行了表征。 相似文献
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设计、合成并用红外光谱、1H NMR、元素分析表征了三种用于双光子吸收材料的二苯乙烯衍生物,4,4′-双(二苯氨基-反式-苯乙烯基)联苯(BPSBP),4,4′-双(二乙氨基-反式-苯乙烯基)联苯(BESBP)和4,4′-双(9-咔唑基-反式-苯乙烯基)联苯(BCSBP)。实验结果表明三者最强的单光子吸收出现在350~400 nm之间,且单光子吸收和荧光光谱中表现出明显的溶剂化显色效应,揭示了分子内对称电荷转移的本质,双光子荧光光谱则揭示了单光子和双光子吸收具有相同的发射机理。利用双光子上转换荧光法测试发现,三种双光子吸收材料在800 nm飞秒激光的激发下具有较大的吸收截面,分别为892,617和483 GM,这表明在双光子领域有潜在的应用价值。 相似文献
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Fang Gao Jian Liu Huayong Peng Nvdan Hu Hongru Li Shengtao Zhang 《Journal of fluorescence》2010,20(3):703-712
In this article, we presented novel nitro-stilbene derivatives with one or two benzophenone groups as photoinitiators via
multi-steps synthesis. The ultraviolet/visible spectroscopy and the emission spectroscopy of the compounds were determined
in various solvents. The results showed that the ultraviolet/visible absorption spectroscopy of the derivatives with benzophenone
moiety displayed overlap effects of nitro-stilbene and benzophenone parts. In non-polar solvents, the derivatives exhibited
strong emission, while they displayed weak emission in modest and strong polar solvents. Dyes-linked benzopheonone groups
displayed stronger fluorescence emission than simple chromophore parent molecules. Visible-light photoinitiating effects of
the derivatives were investigated extensively. Methyl methacrylate could be photoinitiated efficiently by the derivatives
with benzophenone moieties at very low concentration, even at 1 × 10−5 mol/L. While the photopolymerization efficiency of styrene initiated by the derivatives was lower than that of methyl methacrylate.
Our results showed that the dye-linked photoinitators had more efficient photoinitiating than the simple mixture of dye and
photoinitator. Furthermore, the derivative with two benzophenone groups displayed more excellent phototiniatiating effects
than the derivative with one benzophenone group. Thermodynamics driving for the occurrence of visible-light photoinduced intramolecular
electron transfer from chromophore part to benzophenone part was evaluated. Benzopinacol moiety produced in photoreaction
was confirmed by nuclear magnetic resonant spectroscopy. Thermal stability of the derivatives was analyzed. 相似文献
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Properties of benzanthrone aminoderivative ABM (conditional name) as a potential fluorescent probe were investigated. Spectral characteristics of the compound in different solvents as well as their binding to model lipid membranes (liposomes) and human peripheral blood mononuclear cells (lymphocytes; ly) were determined. The fluorescence was found to be sensitive polarity changes to the environment. Distinctions were observed in the spectral characteristics of the investigated compound when bounded to liposomes. It was established that spectral characteristics of ABM in cell suspension qualitatively characterize the structural and functional alterations of ly during pathological phenomena and correlate directly with the clinical view of disease. The ABM is shown to be a perspective in the screening for various pathologies. 相似文献
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A novel fluorescent dye bis-(pyridin-2-yl-methyl)-(1,3,4-triphenyl-1H-pyrazolo[3,4-b]quinolin-6-ylmethyl)-amine (P1) has been synthesized and investigated by means of steady state and time-resolved fluorescence techniques. This compound acts as sensor for fluorescence detection of small inorganic cations (lithium, sodium, barium, magnesium, calcium, and zinc) in highly polar solvents such as acetonitrile. The mechanism which allows application of this compound as sensor is an electron transfer from the electron-donative part of molecule (amine) to the acceptor part (pyrazoloquinoline derivative), which is retarded upon complexation of the electro-donative part by inorganic cations. The binding constants are strongly dependent on the charge density of the analyzed cations. The 2/1 complexes of P1 with Zn(++) and Mg(++) cations posses large binding constants. Moreover, in the presence of these cations a significant bathochromic shift of fluorescence is observed. The most probable explanation of such behaviour is the formation of intramolecular excimer. This is partially supported by the quantum chemical calculations. 相似文献
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Four novel derivatives of BINOL bearing S-tryptophan unit have been prepared and the structures of these compounds characterized
by IR, MS, 1H and 13C NMR spectroscopy and elemental analysis. The enantioselective recognition of these receptors has been studied by fluorescence
titration and 1H NMR spectroscopy. The receptors exhibited different chiral recognition abilities towards N-Boc-protected amino acid anions
and formed 1:1 complexes between host and guest. Receptors exhibit excellent enantioselective fluorescent recognition ability
towards the amino acid derivatives. 相似文献