- Precise one-pot synthesis of end-functionalized conjugated multi-block copolymers via combined olefin metathesis and wittig-type coupling
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A precise, one-pot synthesis of end-functionalized block copolymers consisting of poly(9,9-di-n-octylfluorene-2,7-vinylene)s (PFVs) and oligo(2,5-dialkoxy-1,4-phenylenevinylene) or terthiophene units as the middle segment have been prepared by olefin metathesis of the vinyl group in the PFV chain ends followed by subsequent Wittig-type coupling. Formation of the block copolymers and the quantitative efficiency in the end-functionalization can be confirmed by synthesis of amphiphilic block copolymers containing poly(ethylene glycol) at the both polymer chain ends. Effect of PFV conjugation length, middle segment, and the end groups toward the emission properties have been studied: the polymers containing ferrocene moiety at the chain ends displayed unique emission/quenching properties.
- Nomura, Kotohiro,Haque, Tahmina,Onuma, Taira,Hajjaj, Fatin,Asano, Motoko S.,Inagaki, Akiko
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- The Tetrathioporphycene Redox System: Electrochemical Reduction of a 20? Cyclophane to Its Diatropic 22? Dianion
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The reductive carbonyl coupling (McMurry reaction) of 5,5'-diformyl-2,2'-bithiophene affords the fourfold sulfur bridged annulene 5 and its annulene homologue 10 in 8 and 3percent yields.Coupling of 5,5''-diformyl-2,2':5',2''-terthiophene produces structurally related macrocycles, albeit in very low yields.As shown by X-ray crystallographic investigation, the bridged annulenes 5 and 10 are non-planar cyclophanes exhibiting transannular electronic interaction.The sulfur bridged annulene 5 constitutes the central molecule of the tetrathiaporphycene redox system emcompassing the dicationic tetrathiaporphycene 3, the annulene 5, the 22? dianion 8 and the two intermediate radical ion species.Compound 5 is reduced in one two-electron step giving the diatropic 22-? dianion 8 which is characterized by cyclovoltammetry, coulometry, spectroelectrochemistry and 1H-NMR spectroscopy.By contrast, 5 fails to undergo oxidation with formation of the dicationic 18? tetrathioporphycene. - Keywords.McMurry reaction; 1H-NMR; Crystal structure; Voltammetry; Coulometry; Spectroelectrochemistry.
- Ellinger, F.,Gieren, A.,Huebner, Th.,Lex, J.,Lucchesini, F.,et al.
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- Efficient synthesis of RITA and its analogues: Derivation of analogues with improved antiproliferative activity via modulation of p53/miR-34a pathway
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A novel approach to synthesize RITA by practical palladium-catalyzed C-C bond-forming Suzuki reactions at room temperature was developed, which was used for deriving a series of substituted tricyclic α-heteroaryl (furan/thiophene) analogues of RITA under mild conditions. These novel analogues showed notable antiproliferative activity against cancer cell lines with wild-type p53 (i.e., HCT116, A549, MCF-7 and K562), but much less activity in HCT116/p53-/- cells. In particular, compound 1f demonstrated promising antiproliferative activity compared to RITA, with IC50 = 28 nM in MCF-7 vs. 54 nM for RITA, and cancer cell selectivity. Compound 1f markedly activated p53 in HCT116 cells at 100 nM, triggering apoptosis. Importantly, we found that both RITA and compound 1f induced G 0/G1 cell cycle arrest by up-regulating miR-34a, which in turn down-regulated the expression of cell cycle-related proteins CDK4 and E2F1. In summary, this study reports an effective synthetic approach for RITA and its analogues, and elucidates a novel antiproliferative mechanism of these compounds. The Royal Society of Chemistry 2012.
- Lin, Jinshun,Jin, Xiuli,Bu, Yiwen,Cao, Deliang,Zhang, Nannan,Li, Shangfu,Sun, Qinsheng,Tan, Chunyan,Gao, Chunmei,Jiang, Yuyang
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- Synthesis and photophysical characterization of new fluorescent bis-amino acids bearing a heterocyclic bridge containing benzoxazole and thiophene
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A series of new bis-alanine derivatives bearing (oligo)thiophene and benzoxazole units as the heteroaromatic bridge were synthesized in moderate to good yields. The photophysical characterization of these bis-amino acids was performed by UV-vis absorption and fluorescence emission studies and revealed that the compounds displayed exceptionally high fluorescence quantum yields, making them good candidates for application as fluorescent probes when incorporated into peptides, as well as peptide conformation-restricting and cross-linking elements.
- Costa, Susana P.G.,Batista, Rosa M.F.,Raposo, M. Manuela M.
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- Thiophene-substituted fulleropyrrolidine derivatives as acceptor molecules in a thin film organic solar cell
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A study of the design of thiophene-substituted fulleropyrrolidine derivatives as the acceptor in photovoltaic cells has been carried out using poly(3-hexylthiophene) (P3HT) as the model donor polymer. It was found that five types of thiophene-substituted fulleropyrrolidine worked as a good acceptor partner with P3HT, and the highest power conversion efficiency (PCE) was obtained for 1-(2-(2-methoxyethoxy)ethyl)-2-(2-thiophen-2-yl)fulleropyrrolidine (2.99%); this is superior to that of the P3HT polymer including methyl [C60]-PCBM under the same experimental conditions.
- Yoshimura, Ken,Matsumoto, Kei,Uetani, Yasunori,Sakumichi, Shigeki,Hayase, Shuichi,Kawatsura, Motoi,Itoh, Toshiyuki
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- Synthesis and antiproliferative activity of RITA and its analogs
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The synthesis of RITA and a variety of five-membered heterocyclic triads by the cyclocondensation of 1,4-bis(5-substituted-2-thienyl or 2-furyl)-1,3-butadiynes with water or Na2S·9H2O in the presence of KOH in DMSO is described. The study on the antiproliferative activities against K562, MCF-7, A549, and HCT116 tumor cells has revealed that some of the heterocyclic triads show higher antiproliferative activities than RITA, depending on the structures of substituents, the property of heteroatoms as well as their numbers.
- Jiang, Jianhua,Ding, Chao,Li, Lulu,Gao, Chunmei,Jiang, Yuyang,Tan, Chunyan,Hua, Ruimao
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supporting information
p. 6635 - 6638
(2015/01/16)
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- Dicyanovinyl-substituted oligothiophenes: Structure-property relationships and application in vacuum-processed small molecule organic solar cells
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Efficient synthesis of a series of terminally dicyanovinyl (DCV)-substituted oligothiophenes, DCVnT 1-6, without solubilizing side chains synthesized via a novel convergent approach and their application as electron donors in vacuum-processed m-i-p-type planar and p-i-n-type bulk heterojunction organic solar cells is described. Purification of the products via gradient sublimation yields thermally highly stable organic semiconducting materials in single crystalline quality which allows for X-ray structure analysis. Important insights into the packing features and intermolecular interactions of these promising solar cell materials are provided. Optical absorption spectra and electrochemical properties of the oligomers are investigated and valuable structure-property relationships deduced. Photovoltaic devices incorporating DCVnTs 4-6 showed power conversion efficiencies up to 2.8% for planar and 5.2% for bulk heterojunction organic solar cells under full sun illumination (mismatch corrected simulated AM 1.5G sunlight). The 5.2% efficiency shown here represents one of the highest values ever reported for organic vacuum-deposited single heterojunction solar cells.
- Fitzner, Roland,Reinold, Egon,Mishra, Amaresh,Mena-Osteritz, Elena,Baeuerle, Peter,Ziehlke, Hannah,Koerner, Christian,Leo, Karl,Riede, Moritz,Weil, Matthias,Tsaryova, Olga,Weiss, Andre,Uhrich, Christian,Pfeiffer, Martin
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body text
p. 897 - 910
(2012/02/16)
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- Synthesis and photovoltaic properties of formyl end-capped oligothiophenes
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For the purpose of developing novel photovoltaic materials, 5,5″-biformyl-2,2′:5′,2″-terthiophene (OHC-3T-CHO) and 5,5″-biformyl-2,2′:5′,2″:5″,2?:5?, 2″″-q-uinquethiophene (OHC-5T-CHO) were synthesized. The photovoltaic properties of OHC-3T-CHO and OHC-5T-CHO were studied. We have fabricated two flexible organic photovoltaic devices using OHC-3T-CHO, OHC-5T-CHO, and 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA). The PET-ITO (indium tin oxides coated with polyethylene terephthalate)/OHC-3T-CHO/ PTCDA/Al device has an open circuit voltage (Voc) of 1.12V, and photoelectric conversion efficiency (PCE) of 1.00%, whereas the PET-ITO/OHC-5T-CHO/PTCDA/Al device has a Voc of 1.78V and PCE of 1.08%. Both devices have high Voc (1.12V and 1.78V). It is possible that intermolecular hydrogen bonding between the -CHO group of OHC-nT-CHO and the carboxylic dianhydride of PTCDA enhanced the efficiency by promoting forward interfacial electron transfer.
- Jiang, Chuanyu,Liu, Ping,Deng, Wenji
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experimental part
p. 2360 - 2369
(2009/11/30)
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- Thiophene-based glass-forming hole-transporting hydrazones
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The synthesis, optical, thermal, and photoelectrical properties of new thiophene-based hydrazones are reported. The ionization potentials of the films of thiophene-based hydrazones, measured by the electron photoemission technique, range from 4.99 to 5.58∈eV. Hole-drift mobilities in the solid solutions in bisphenol-Z polycarbonate (PC-Z) of the synthesized hydrazones were studied by time of flight technique. Room temperature charge mobilities in the solid solution of 5,2″-diformyl-2,2′:5′″me;-terthiophene di(N,N-diphenylhydrazone) in PC-Z exceeded 10-5∈cm 2/Vs at high applied electric fields.
- Michaleviciute, Asta,Ostrauskaite, Jolita,Buika, Gintaras,Grazulevicius, Juozas Vidas,Jankauskas, Vygintas,Tran Van, Francois,Chevrot, Claude
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scheme or table
p. 1011 - 1017
(2009/12/01)
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- Novel protein kinase C inhibitors: α-terthiophene derivatives
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A series of α-terthiophene derivatives were prepared and their protein kinase C inhibitory activity were evaluated. The aldehyde derivatives were most potent inhibitors (IC50 1 μM). 2a-Terthiophene monoaldehyde was inactive in the inhibitions of protein kinase A, mitogen activated protein kinase and protein tyrosine kinase.
- Kim, Darrick S. H. L.,Ashendel, Curtis L.,Zhou, Qin,Chang, Ching-Te,Lee, Eung-Seok,Chang, Ching-Jer
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p. 2695 - 2698
(2007/10/03)
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- Extensively Conjugated Tetrathiafulvalene (TTF) ?-Electron Donors with Oligothiophenes Spacer Groups
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New extended p-donors combining the tetrathiafulvalene (TTF) system with the conjugated backbone of substituted terthienyls are described.
- Roncali, Jean,Giffard, Michel,Frere, Pierre,Jubault, Michel,Gorgues, Alain
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p. 689 - 691
(2007/10/02)
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- SYNTHESIS AND CHARACTERIZATION OF ALKYL-, HALO- AND HETEROSUBSTITUTED DERIVATIVES OF THE POTENT PHOTOTOXIN &α-TERTHIENYL
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A number of derivatives of α-terthienyl were prepared including a series of naturally occurring compounds.A description of the syntheses of some new compounds, including 5-iodo, 5,5''-diiodo, 5,5''-diformyl, 5,5''-di-tert butyl, 5-tert-butyl, 5-tert-butoxy, 5-trimethylsilyl, 5-thiomethyl, 5,5''-dithiomethyl and 5-carboxyl-5''-(trimethylsilyl)-2,2':5',2''-terthienyl is also given.An analysis of the 1H NMR data of the derivatives is presented.
- Eachern, Anita Mac,Soucy, Chantal,Leitch, Leonard C.,Arnason, John T.,Morand, Peter
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p. 2403 - 2412
(2007/10/02)
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