The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Gervais Bérubé - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and Preliminary in Vitro Cytotoxic Activity of New Triphenylethylene Dimers
Bioorganic Chemistry, 1999Co-Authors: Serge Groleau, Gervais Bérubé, Josée Nault, Martine Lepage, Michelle Couture, Normand Dallaire, René C.-gaudreaultAbstract:Abstract We have synthesized a series of six nonsteroidal homo- and heterobifunctional estrogenic dimers designed for the treatment of breast cancer. They are made of two Triphenylethylene moieties linked by an aliphatic chain. The synthesis used six steps, from the known alcohol 5 , with an overall yield of more than 60%. This article describes the synthesis of these products and their in vitro biological activity on two human breast cancer cell lines: MCF-7 and MDA-MB-231. The dimers are generally less active than tamoxifen, which presents an IC 50 = 16 and 40 μM on MCF-7 and MDA-MB-231 cell lines, respectively. However, the symmetrical dimer bearing six hydroxy functions possesses the best in vitro cytotoxic activity of the series, showing an IC 50 = 38 μM on both types of cells. It was observed that the cytotoxicity of the dimers increases with the number of hydroxy groups present on the aromatic rings.
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Effects of New Triphenylethylene Platinum(II) Complexes on the Interaction with Phosphatidylcholine Liposomes.
CHEMICAL & PHARMACEUTICAL BULLETIN, 1998Co-Authors: Guillaume Grenier, Gervais Bérubé, Claude GicquaudAbstract:In a previous work we synthesized a class of new antineoplastic drugs by coupling a cisplatin derivative to a Triphenylethylene moiety similar to the antiestrogen, tamoxifen. These drugs differ in the number of hydroxy functions on the Triphenylethylene rings and in the length of the linking arm.To gain more insight into the cellular mechanism by which these new drugs act on cells, we studied, using differential scanning calorimetry, the effects of these compounds on the phase transition of membrane phospholipid (distearoyl phosphatidyl choline (DSPC)), and correlated these effects to drug cytotoxicity. The drugs without hydroxy function showed the highest cytotoxicity and induced little change on the thermogram of DSPC. Contrarily, the drugs bearing two or three hydroxy groups were less toxic, but induced important modifications of the thermogram.We suggest that the drugs with no hydroxy group enter the membrane, with the Triphenylethylene moiety localized deep within the hydrophobic core of the bilayer and do not affect the cooperativity region (C2-C8). In contrast, drugs which bear hydroxy grops on the Triphenylethylene rings system perturb the phospholipid molecular arrangement; this may be due either to the additional steric hindrance of te hydroxy functions in the core of the bilayer, or to their hydrophilic effect on the polar head of the lipid.In vitro, the cytotoxic effect of these drugs seems not to be related to their affinity for the estrogen receptor. We suggest that the addition of a Triphenylethylene moiety to the platinum(II) complexes increases the hydrophobicity, and consequently the resulting drugs become more permeable to the membrane, particularly the non-hydroxylated Triphenylethylene derivatives.
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The synthesis and characterization of new Triphenylethylene platinum(II) complexes
Inorganica Chimica Acta, 1997Co-Authors: Gervais Bérubé, Serge Groleau, Alexandre Séné, Hélène-marie Thérien, Madeleine CaronAbstract:Abstract In our search for a chemotherapeutic agent with a better therapeutic index and selectivity for the treatment of breast cancer, we have synthesized a series of cytotoxic analogs of tamoxifen. The new Triphenylethylene platinum(II) derivatives were designed to possess binding affinity for the estrogen receptor. The synthesis of this type of compound is straightforward and efficient. The new complexes were fully characterized by their IR, 1H NMR and 13C NMR spectra as well as their elemental analysis. The estrogen receptor binding affinity (RBA) of some of these Triphenylethylenes was also evaluated and was found to be comparable to the affinity of the reference drug, i.e. tamoxifen, RBA=1.3%.
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Synthesis and in vitro biological evaluation of new Triphenylethylene platinum (II) complexes
Bioorganic & Medicinal Chemistry Letters, 1995Co-Authors: Serge Groleau, Hélène-marie Thérien, Madeleine Caron, René C.-gaudreault, Gervais BérubéAbstract:Abstract In our search for a chemotherapeutic agent with a better therapeutic index and selectivity for the treatment of breast cancer, we have synthesized cytotoxic Triphenylethylene derivatives. The synthesis of this type of compound is straightforward and efficient. The biological activity of these compounds was evaluated in vitro on ER+ and ER- human breast tumor cell lines: MCF-7 and MDA-MB-231.
Siwei Liu - One of the best experts on this subject based on the ideXlab platform.
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Combined aggregation induced emission (AIE), photochromism and photoresponsive wettability in simple dichloro-substituted Triphenylethylene derivatives
Chemical Science, 2016Co-Authors: Ou Depei, Zhiyong Yang, Tiangang Luan, Zhu Mao, Yi Zhang, Siwei Liu, Zhenguo Chi, Martin R. BryceAbstract:A dichloro-substituted Triphenylethylene derivative (TrPECl2) with aggregation-induced emission (AIE), photochromism and photoresponsive wettability has been synthesized. The new compound shows fast-response photochromic behaviour with good ON/OFF repeatability by utilizing a proposed stilbene-type intramolecular photocyclization in the solid state. Compared with the more usual diphenylethylene derivatives, the photochromic properties of the Triphenylethylene derivative are much more striking and easier to achieve. The Triphenylethylene derivative also displays AIE properties leading to strong fluorescence in the solid state. Therefore, both the ultraviolet-visible absorption and fluorescence emission are drastically changed during the photochromic processes. Furthermore, the morphology of the TrPECl2 microcrystalline surface could be controlled by irradiation. The wettability of the surface could be drastically decreased with contact angles of a water droplet changing from 73° to 118°. The Triphenylethylene derivative with a simple molecular structure is, therefore, attractive for multifunctional materials.
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High-Performance Functional Polyimides Containing Rigid Nonplanar Conjugated Triphenylethylene Moieties
2016Co-Authors: Yiwu Liu, Yi Zhang, Siwei Liu, Zhenguo Chi, Qi Lan, Zexin Qin, Lianghui Chen, Cunyuan Zhao, James EconomyAbstract:A novel, simple but efficient diamine (TriPEDA) containing rigid nonplanar conjugated Triphenylethylene moieties was designed and synthesized through Wittig–Horner and Suzuki coupling reactions. Four kinds of high-performance functional polyimides were thus prepared by the dipolymerization of TriPEDA and four dianhydrides, respectively. Because of the introduction of the aromatic rigid nonplanar Triphenylethylene structure, the polyimides exhibited special fluorescent and resistive switching (ON-OFF) characteristics, as the maximum fluorescence emission of the four polyimides was observed at 472–505 nm in NMP solution and at 473–541 nm in film state. Also these organo-soluble polyimides showed outstanding properties, such as low dielectric constant (even without fluorinated substituents), light color, high glass transition temperatures (359–409 °C), thermal stability, and excellent mechanical properties. The memory devices with the configuration of indium tin oxide/polyimides/aluminum (ITO/PI/Al) exhibited distinct volatile memory characteristics of static random access memory (SRAM), with an ON/OFF current ratio of 1 × 105 to 1 × 106. These functional polyimides showed attractive potential applications in the field of high-performance flexible polymer photoconducting devices or polymer memory devices
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high performance functional polyimides containing rigid nonplanar conjugated Triphenylethylene moieties
Chemistry of Materials, 2012Co-Authors: Yiwu Liu, Yi Zhang, Siwei Liu, Zhenguo Chi, Qi Lan, Zexin Qin, Lianghui Chen, Cunyuan Zhao, James EconomyAbstract:A novel, simple but efficient diamine (TriPEDA) containing rigid nonplanar conjugated Triphenylethylene moieties was designed and synthesized through Wittig–Horner and Suzuki coupling reactions. Four kinds of high-performance functional polyimides were thus prepared by the dipolymerization of TriPEDA and four dianhydrides, respectively. Because of the introduction of the aromatic rigid nonplanar Triphenylethylene structure, the polyimides exhibited special fluorescent and resistive switching (ON-OFF) characteristics, as the maximum fluorescence emission of the four polyimides was observed at 472–505 nm in NMP solution and at 473–541 nm in film state. Also these organo-soluble polyimides showed outstanding properties, such as low dielectric constant (even without fluorinated substituents), light color, high glass transition temperatures (359–409 °C), thermal stability, and excellent mechanical properties. The memory devices with the configuration of indium tin oxide/polyimides/aluminum (ITO/PI/Al) exhibite...
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Metal-free organic dyes derived from Triphenylethylene for dye-sensitized solar cells: tuning of the performance by phenothiazine and carbazole
Journal of Materials Chemistry, 2012Co-Authors: Chengjian Chen, Yi Zhang, Zhenguo Chi, Jin-yun Liao, Xiqi Zhang, Dai-bin Kuang, Siwei LiuAbstract:Four novel D–D–π–A configuration metal-free organic dyes (C3, P2, C2 and P3) with Triphenylethylene phenothiazine moieties or Triphenylethylene carbazole moieties as additional electron donors for dye-sensitized solar cells (DSSCs) have been synthesized. The cells based on C3, P2, C2 and P3 dyes with efficiencies of 2.14%, 2.69%, 5.51% and 6.55%, respectively, are obtained. The P3 based cell exhibits the highest efficiency of 6.55% accompanied by a short-circuit current density (Jsc) of 12.18 mA cm−2, a rather high open-circuit photovoltage (Voc) of 826 mV, and a fill factor (ff) of 0.65, performances which are remarkable in the DSSCs based on metal-free organic dyes. The twisted non-planar configuration in P3 decelerates the charge recombination in the charge-separated state and hence contributes to the improvement of the performance of DSSCs.
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Piezofluorochromic and aggregation-induced-emission compounds containing Triphenylethylene and tetraphenylethylene moieties.
Chemistry - An Asian Journal, 2011Co-Authors: Zhenguo Chi, Siwei Liu, Xiqi Zhang, Jianyong Zhang, Yi ZhangAbstract:New fluorescent compounds containing Triphenylethylene and tetraphenylethylene moieties were synthesized, and their piezofluorochromic and aggregation-induced emission behaviors were investigated. The results show that all compounds exhibit aggregation-induced emission characteristics and only the crystalline compound possesses piezofluorochromic properties. The color, emission spectra, and morphological structures of the one piezofluorochromic compound exhibit reversibility upon grinding and annealing (or fuming) treatments. The piezofluorochromic behaviors are caused by a change between different modes of solid state molecular packing under external pressure. The single crystal X-ray diffraction analysis reveals that the twisted conformation of the aggregation-induced emission compound leads to the formation of metastable crystal lattice with cavity which is readily destroyed under external pressure. A possible mechanism of piezofluorochromic phenomenon has been proposed.
Yi Zhang - One of the best experts on this subject based on the ideXlab platform.
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Combined aggregation induced emission (AIE), photochromism and photoresponsive wettability in simple dichloro-substituted Triphenylethylene derivatives
Chemical Science, 2016Co-Authors: Ou Depei, Zhiyong Yang, Tiangang Luan, Zhu Mao, Yi Zhang, Siwei Liu, Zhenguo Chi, Martin R. BryceAbstract:A dichloro-substituted Triphenylethylene derivative (TrPECl2) with aggregation-induced emission (AIE), photochromism and photoresponsive wettability has been synthesized. The new compound shows fast-response photochromic behaviour with good ON/OFF repeatability by utilizing a proposed stilbene-type intramolecular photocyclization in the solid state. Compared with the more usual diphenylethylene derivatives, the photochromic properties of the Triphenylethylene derivative are much more striking and easier to achieve. The Triphenylethylene derivative also displays AIE properties leading to strong fluorescence in the solid state. Therefore, both the ultraviolet-visible absorption and fluorescence emission are drastically changed during the photochromic processes. Furthermore, the morphology of the TrPECl2 microcrystalline surface could be controlled by irradiation. The wettability of the surface could be drastically decreased with contact angles of a water droplet changing from 73° to 118°. The Triphenylethylene derivative with a simple molecular structure is, therefore, attractive for multifunctional materials.
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Combined aggregation induced emission (AIE), photochromism and photoresponsive wettability in simple dichloro-substituted Triphenylethylene derivatives.
'Royal Society of Chemistry (RSC)', 2016Co-Authors: Ou Depei, Yi Zhang, Yu Tao, Yang Zhiyong, Luan Tiangang, Mao Zhu, Liu Siwei, Xu Jiarui, Chi Zhenguo, Bryce, Martin R.Abstract:A dichloro-substituted Triphenylethylene derivative (TrPECl2) with aggregation-induced emission (AIE), photochromism and photoresponsive wettability has been synthesized. The new compound shows fast-response photochromic behaviour, with good ON/OFF repeatability by utilizing a proposed stilbene-type intramolecular photocyclization in the solid state. Compared with the more usual diphenylethylene derivatives, the photochromic properties of the Triphenylethylene derivative is much more striking and easier to achieve. The Triphenylethylene derivative also displays AIE properties leading to strong fluorescence in the solid state. Therefore, both the ultraviolet-visible absorption and fluorescence emission are drastically changed during the photochromic processes. Furthermore, the morphology of the TrPECl2 microcrystalline surface could be controlled by irradiation. The wettability of the surface could be drastically decreased with contact angles of a water droplet changing from 73o to 118o. The Triphenylethylene derivative with a simple molecular structure is, therefore, attractive for multifunctional materials
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High-Performance Functional Polyimides Containing Rigid Nonplanar Conjugated Triphenylethylene Moieties
2016Co-Authors: Yiwu Liu, Yi Zhang, Siwei Liu, Zhenguo Chi, Qi Lan, Zexin Qin, Lianghui Chen, Cunyuan Zhao, James EconomyAbstract:A novel, simple but efficient diamine (TriPEDA) containing rigid nonplanar conjugated Triphenylethylene moieties was designed and synthesized through Wittig–Horner and Suzuki coupling reactions. Four kinds of high-performance functional polyimides were thus prepared by the dipolymerization of TriPEDA and four dianhydrides, respectively. Because of the introduction of the aromatic rigid nonplanar Triphenylethylene structure, the polyimides exhibited special fluorescent and resistive switching (ON-OFF) characteristics, as the maximum fluorescence emission of the four polyimides was observed at 472–505 nm in NMP solution and at 473–541 nm in film state. Also these organo-soluble polyimides showed outstanding properties, such as low dielectric constant (even without fluorinated substituents), light color, high glass transition temperatures (359–409 °C), thermal stability, and excellent mechanical properties. The memory devices with the configuration of indium tin oxide/polyimides/aluminum (ITO/PI/Al) exhibited distinct volatile memory characteristics of static random access memory (SRAM), with an ON/OFF current ratio of 1 × 105 to 1 × 106. These functional polyimides showed attractive potential applications in the field of high-performance flexible polymer photoconducting devices or polymer memory devices
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high performance functional polyimides containing rigid nonplanar conjugated Triphenylethylene moieties
Chemistry of Materials, 2012Co-Authors: Yiwu Liu, Yi Zhang, Siwei Liu, Zhenguo Chi, Qi Lan, Zexin Qin, Lianghui Chen, Cunyuan Zhao, James EconomyAbstract:A novel, simple but efficient diamine (TriPEDA) containing rigid nonplanar conjugated Triphenylethylene moieties was designed and synthesized through Wittig–Horner and Suzuki coupling reactions. Four kinds of high-performance functional polyimides were thus prepared by the dipolymerization of TriPEDA and four dianhydrides, respectively. Because of the introduction of the aromatic rigid nonplanar Triphenylethylene structure, the polyimides exhibited special fluorescent and resistive switching (ON-OFF) characteristics, as the maximum fluorescence emission of the four polyimides was observed at 472–505 nm in NMP solution and at 473–541 nm in film state. Also these organo-soluble polyimides showed outstanding properties, such as low dielectric constant (even without fluorinated substituents), light color, high glass transition temperatures (359–409 °C), thermal stability, and excellent mechanical properties. The memory devices with the configuration of indium tin oxide/polyimides/aluminum (ITO/PI/Al) exhibite...
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Metal-free organic dyes derived from Triphenylethylene for dye-sensitized solar cells: tuning of the performance by phenothiazine and carbazole
Journal of Materials Chemistry, 2012Co-Authors: Chengjian Chen, Yi Zhang, Zhenguo Chi, Jin-yun Liao, Xiqi Zhang, Dai-bin Kuang, Siwei LiuAbstract:Four novel D–D–π–A configuration metal-free organic dyes (C3, P2, C2 and P3) with Triphenylethylene phenothiazine moieties or Triphenylethylene carbazole moieties as additional electron donors for dye-sensitized solar cells (DSSCs) have been synthesized. The cells based on C3, P2, C2 and P3 dyes with efficiencies of 2.14%, 2.69%, 5.51% and 6.55%, respectively, are obtained. The P3 based cell exhibits the highest efficiency of 6.55% accompanied by a short-circuit current density (Jsc) of 12.18 mA cm−2, a rather high open-circuit photovoltage (Voc) of 826 mV, and a fill factor (ff) of 0.65, performances which are remarkable in the DSSCs based on metal-free organic dyes. The twisted non-planar configuration in P3 decelerates the charge recombination in the charge-separated state and hence contributes to the improvement of the performance of DSSCs.
Madeleine Caron - One of the best experts on this subject based on the ideXlab platform.
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The synthesis and characterization of new Triphenylethylene platinum(II) complexes
Inorganica Chimica Acta, 1997Co-Authors: Gervais Bérubé, Serge Groleau, Alexandre Séné, Hélène-marie Thérien, Madeleine CaronAbstract:Abstract In our search for a chemotherapeutic agent with a better therapeutic index and selectivity for the treatment of breast cancer, we have synthesized a series of cytotoxic analogs of tamoxifen. The new Triphenylethylene platinum(II) derivatives were designed to possess binding affinity for the estrogen receptor. The synthesis of this type of compound is straightforward and efficient. The new complexes were fully characterized by their IR, 1H NMR and 13C NMR spectra as well as their elemental analysis. The estrogen receptor binding affinity (RBA) of some of these Triphenylethylenes was also evaluated and was found to be comparable to the affinity of the reference drug, i.e. tamoxifen, RBA=1.3%.
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Synthesis and in vitro biological evaluation of new Triphenylethylene platinum (II) complexes
Bioorganic & Medicinal Chemistry Letters, 1995Co-Authors: Serge Groleau, Hélène-marie Thérien, Madeleine Caron, René C.-gaudreault, Gervais BérubéAbstract:Abstract In our search for a chemotherapeutic agent with a better therapeutic index and selectivity for the treatment of breast cancer, we have synthesized cytotoxic Triphenylethylene derivatives. The synthesis of this type of compound is straightforward and efficient. The biological activity of these compounds was evaluated in vitro on ER+ and ER- human breast tumor cell lines: MCF-7 and MDA-MB-231.
Serge Groleau - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and Preliminary in Vitro Cytotoxic Activity of New Triphenylethylene Dimers
Bioorganic Chemistry, 1999Co-Authors: Serge Groleau, Gervais Bérubé, Josée Nault, Martine Lepage, Michelle Couture, Normand Dallaire, René C.-gaudreaultAbstract:Abstract We have synthesized a series of six nonsteroidal homo- and heterobifunctional estrogenic dimers designed for the treatment of breast cancer. They are made of two Triphenylethylene moieties linked by an aliphatic chain. The synthesis used six steps, from the known alcohol 5 , with an overall yield of more than 60%. This article describes the synthesis of these products and their in vitro biological activity on two human breast cancer cell lines: MCF-7 and MDA-MB-231. The dimers are generally less active than tamoxifen, which presents an IC 50 = 16 and 40 μM on MCF-7 and MDA-MB-231 cell lines, respectively. However, the symmetrical dimer bearing six hydroxy functions possesses the best in vitro cytotoxic activity of the series, showing an IC 50 = 38 μM on both types of cells. It was observed that the cytotoxicity of the dimers increases with the number of hydroxy groups present on the aromatic rings.
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The synthesis and characterization of new Triphenylethylene platinum(II) complexes
Inorganica Chimica Acta, 1997Co-Authors: Gervais Bérubé, Serge Groleau, Alexandre Séné, Hélène-marie Thérien, Madeleine CaronAbstract:Abstract In our search for a chemotherapeutic agent with a better therapeutic index and selectivity for the treatment of breast cancer, we have synthesized a series of cytotoxic analogs of tamoxifen. The new Triphenylethylene platinum(II) derivatives were designed to possess binding affinity for the estrogen receptor. The synthesis of this type of compound is straightforward and efficient. The new complexes were fully characterized by their IR, 1H NMR and 13C NMR spectra as well as their elemental analysis. The estrogen receptor binding affinity (RBA) of some of these Triphenylethylenes was also evaluated and was found to be comparable to the affinity of the reference drug, i.e. tamoxifen, RBA=1.3%.
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Synthesis and in vitro biological evaluation of new Triphenylethylene platinum (II) complexes
Bioorganic & Medicinal Chemistry Letters, 1995Co-Authors: Serge Groleau, Hélène-marie Thérien, Madeleine Caron, René C.-gaudreault, Gervais BérubéAbstract:Abstract In our search for a chemotherapeutic agent with a better therapeutic index and selectivity for the treatment of breast cancer, we have synthesized cytotoxic Triphenylethylene derivatives. The synthesis of this type of compound is straightforward and efficient. The biological activity of these compounds was evaluated in vitro on ER+ and ER- human breast tumor cell lines: MCF-7 and MDA-MB-231.
