- New coumarin dipicolinate europium complexes with a rich chemical speciation and tunable luminescence
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Europium (III) luminescent chelates possess intrinsic photophysical properties that are extremely useful in a wide range of applications. The lack of examples of coumarin-based lanthanide complexes is mainly due to poor photo-sensitization attempts. However, with the appeal of using such a versatile scaffold as antenna, especially in the development of responsive molecular probes, it is worth the effort to research new structural motifs. In this work, we present a series of two new tris coumarin-dipicolinate europium (III) complexes, specifically tailored to be either a mono or a dual emitter, tuning their properties with a simple chemical modification. We also encountered a rich chemical speciation in solution, studied in detail by means of paramagnetic NMR and emission spectroscopy.
- Di Pietro, Sebastiano,Iacopini, Dalila,Moscardini, Aldo,Bizzarri, Ranieri,Pineschi, Mauro,Di Bussolo, Valeria,Signore, Giovanni
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Read Online
- Organoarsenic probes to study proteins by NMR spectroscopy
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Arsenical probes enable structural studies of proteins. We report the first organoarsenic probes for nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) spectroscopy to study proteins in solutions. These probes can be attached to ir
- Adekoya, Ibidolapo,Huber, Thomas,Mahawaththa, Mithun C.,Nitsche, Christoph,Orton, Henry W.,Otting, Gottfried
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supporting information
p. 701 - 704
(2022/01/25)
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- Electron transfer pathways in photoexcited lanthanide(iii) complexes of picolinate ligands
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A series of luminescent lanthanide(iii) complexes consisting of 1,4,7-triazacyclononane frameworks and three secondary amide-linked carbostyril antennae were synthesised. The metal binding sites were augmented with two pyridylcarboxylate donors yielding octadentate ligands. The antennae carried methyl, methoxymethyl or trifluoromethyl substituents in their 4-positions, allowing for a range of excited state energies and antenna electronic properties. The1H NMR spectra of the Eu(iii) complexes were found to be analogous to each other. Similar results were obtained in the solid-state by single-crystal X-ray crystallography, which showed the structures to have nine-coordinate metal ions with heavily distorted tricapped trigonal prismatic geometries. Steady-state and time-resolved luminescence spectroscopy showed that the antennae could sensitize both Tb(iii) and Eu(iii), however, quantum yields were lower than in other octadentate complexes lacking pyridylcarboxylate. Complexes with more electron-poor pyridines were less emissive even when equipped with the same antenna. The oxidation and reduction potentials of the antennae and the pyridinecarboxylates, respectively, were determined by cyclic voltammetry. The obtained values were consistent with electron transfer from the excited antenna to the pyridine providing a previously unexplored quenching pathway that could efficiently compete with energy transfer to the lanthanide. These results show the crucial impact that photophysically innocent ligand binding sites can have on lanthanide luminescence.
- Kovacs, Daniel,Kocsi, Daniel,Wells, Jordann A. L.,Kiraev, Salauat R.,Borbas, K. Eszter
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supporting information
p. 4244 - 4254
(2021/04/06)
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- Luminescent Carbazole-Based EuIII and YbIII Complexes with a High Two-Photon Absorption Cross-Section Enable Viscosity Sensing in the Visible and near IR with One- And Two-Photon Excitation
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The newly synthesized EuIII and YbIII complexes with the new carbazole-based ligands CPAD2- and CPAP4- display the characteristic long-lived metal-centered emission upon one- and two-photon excitation. The EuIII complexes show the expected narrow emission bands in the red region, with emission lifetimes between 0.382 and 1.464 ms and quantum yields between 2.7% and 35.8%, while the YbIII complexes show the expected emission in the NIR region, with emission lifetimes between 0.52 and 37.86 μs and quantum yields between 0.028% and 1.12%. Two-photon absorption cross sections (σ2PA) as high as 857 GM were measured for the two ligands. The complexes showed a strong dependence of the one- and two-photon sensitized emission intensity on solvent viscosity in the range of 0.5-200 cP in the visible and NIR region.
- De Bettencourt-Dias, Ana,Fetto, Natalie R.,Monteiro, Jorge H. S. K.,Tucker, Matthew J.
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supporting information
p. 3193 - 3199
(2020/03/19)
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- FUSED HETEROCYCLIC DERIVATIVES, THEIR PREPARATION METHODS THEREOF AND MEDICAL USES THEREOF
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The present invention relates to fused heterocyclic derivatives, processes for their preparation and their use in medicine. Specifically, the present invention relates to a novel derivative represented by the formula (I′), or its pharmaceutically acceptable salt thereof, a pharmaceutical composition containing the derivative or its pharmaceutically acceptable salt thereof, and the method for preparing the derivative and its pharmaceutically acceptable salt thereof. The present invention also relates to the use of the derivative and its pharmaceutically acceptable salt thereof, or a pharmaceutical composition containing the derivative and its pharmaceutically acceptable salt thereof in the preparation of medicines, in particularly as IDO inhibitor medicines, for treating and/or preventing cancers. Wherein each substituent of the formula (I′) is the same as defined in the specification.
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Paragraph 0246; 0252; 0459; 0460-0462
(2019/07/03)
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- SUBSTITUTED PYRIDINE COMPOUNDS AS PESTICIDES
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The present invention relates to novel substituted pyridine compounds of the formula (I) in which R1, R2, R3, R4, R5, R6, V1, V2 and Q1 have the definitions
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Paragraph 0563-0565
(2019/02/28)
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- LANTHANIDE COMPLEXES FOR CRYSTALLISING BIOLOGICAL MACROMOLECULES AND DETERMINING THE CRYSTALLOGRAPHIC STRUCTURE THEREOF
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The invention relates to cationic complexes made up of a lanthanide ion Ln3+ and a ligand of formula (I) : with X, Y and R1 as defined in claim 1, and to the salts thereof with an anion, the solvates and hydrates thereof; with the exception of cationic complexes made up of a lanthanide ion Ln3+ and a ligand of one of formulae (I.1) or (I.4) as defined in claim 1, and the salts, solvates and hydrates thereof. The invention also relates to the use of such a complex or of a cationic complex made up of a lanthanide ion Ln3+ and a ligand of formula (I.1) or (I.4) as defined in claim 1, or of one of the salts thereof with an anion, the solvates or hydrates thereof, as an aid to the crystallisation of a biological macromolecule, as well as to crystallisation methods and methods for analysing or determining the structure of a biological macromolecule.
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Paragraph 0147; 0148; 0149
(2019/01/04)
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- A formal anti-Markovnikov hydroalkoxylation of allylic alcohols with a ruthenium catalyst
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Hydroalkoxylation of C-C double bonds was achieved through the use of a ruthenium catalyst. The reaction of allylic alcohols with nucleophilic alcohols was carried out in the presence of a ruthenium catalyst prepared by RuClH(CO)(PPh3)3 and 2,6-bis(n-butyliminomethyl)-4-(piperidin-1-yl)pyridine under mild reaction conditions to afford the corresponding γ-alkoxypropanols in good yield.
- Nakamura, Yushi,Ohta, Tetsuo,Oe, Yohei
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supporting information
p. 288 - 291
(2018/02/14)
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- A Highly Stable Organic Radical Cation
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Functionalization of a methylviologen with four methyl ester substituents significantly facilitates the first two reduction steps. The easily generated radical cation shows markedly improved air stability compared to the parent methylviologen, making this derivative of interest in organic electronic applications.
- Berville, Mathilde,Richard, Jimmy,Stolar, Monika,Choua, Sylvie,Le Breton, Nolwenn,Gourlaouen, Christophe,Boudon, Corinne,Ruhlmann, Laurent,Baumgartner, Thomas,Wytko, Jennifer A.,Weiss, Jean
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p. 8004 - 8008
(2019/01/04)
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- WATER-SOLUBLE TRIAZAPYRIDINOPHANE-BASED COMPLEXING AGENTS AND CORRESPONDING FLUORESCENT LANTHANIDE COMPLEXES
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The invention relates to complexing agents of formula (I) in which A1, A2, A3 and R1 are as defined in the description. The invention also relates to lanthanide complexes obtained from said complexing agents. The invention can be used for marking biological molecules.
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Paragraph 0081
(2019/01/04)
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- Selective cytotoxicity and luminescence imaging of cancer cells with a dipicolinato-based EuIII complex
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Four new species [Ln(dipicNH2)3]3- (Ln = LaIII, EuIII, GdIII, TbIII), with the ligand dipicNH22- (dipic = dipicolinato), were synthesized. Incubation of the EuIII complex with glioma NG97 and pancreatic cancer PANC1 cells showed that it penetrates the cell membrane and can be used to image the cells, while also being moderately cytotoxic.
- Monteiro,Machado,De Hollanda,Lancellotti,Sigoli,De Bettencourt-Dias
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supporting information
p. 11818 - 11821
(2017/11/03)
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- Synthesis and Hydrolysis of 4-Chloro-PyMTA and 4-Iodo-PyMTA Esters and Their Oxidative Degradation with Cu(I/II) and Oxygen
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We disclose the syntheses of ethyl and tert-butyl esters of 4-chloro-PyMTA and 4-iodo-PyMTA from the commercially available chelidamic acid monohydrate in 39-67% overall yield. Additionally, ester hydrolyses with aqueous NaOH (ethyl esters) or trifluoroacetic acid (tert-butyl esters) are reported. The resulting materials contain 4-halo-PyMTA in mixture with partially deprotonated or partially protonated 4-halo-PyMTA. The ligand content expressed as the content of the common structural motifs of the present species, namely [PyMTA - 4 H+4- (basic hydrolysis) and PyMTA (acidic hydrolysis), was determined to be 90-94 wt % by1H NMR spectroscopy using maleic acid as an internal standard. The tert-butyl esters were easily hydrolyzed with aqueous alkali hydroxide, with a decreasing rate in the series NaOH, KOH, LiOH. This finding indicates a Lewis acid assisted ester cleavage with the Na+ ion fitting best to the multidentate ligand. Unexpectedly, PyMTA esters are incompatible with Cu(I/II) salts in the presence of oxygen. Under these conditions, one of the two aminomethyl groups is converted into a formyl group. This reaction not only limits the application of Cu(I/II)-catalyzed reactions but also necessitates trapping of any copper ions (e.g., with a metal ion scavenger) before the material is exposed to oxygen.
- Qi, Mian,Hülsmann, Miriam,Godt, Adelheid
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p. 3773 - 3784
(2016/10/30)
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- HETEROARYLAMINOISOQUINOLINES, METHODS FOR THEIR PREPARATION AND THERAPEUTIC USES THEREOF
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The application is directed to compounds of formula (IA) : and specifically compounds of formula (I) and their salts and solvates, wherein R1, R11, R12, R13, R4, R5, n, A1, A2, and A3 are as set forth in the specification, as well as to a method for their preparation, pharmaceutical compositions comprising the same, and use thereof for the treatment and/or prevention of conditions associated with the alteration of the activity of β-galactosidase, specially galactosidase beta-1 or GLB1, including GM1 gangliosidoses and Morquio syndrome, type B.
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Page/Page column 112; 113
(2016/08/23)
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- Linking of antitumor trans NHC-Pt(II) complexes to G-quadruplex DNA ligand for telomeric targeting
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G-quadruplex structures (G4) are promising anticancerous targets. A great number of small molecules targeting these structures have already been identified through biophysical methods. In cellulo, some of them are able to target either telomeric DNA and/o
- Betzer, Jean-Fran?ois,Nuter, Frédérick,Chtchigrovsky, Mélanie,Hamon, Florian,Kellermann, Guillaume,Ali, Samar,Calméjane, Marie-Ange,Roque, Sylvain,Poupon, Jo?l,Cresteil, Thierry,Teulade-Fichou, Marie-Paule,Marinetti, Angela,Bombard, Sophie
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p. 1456 - 1470
(2016/07/06)
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- Separation of Am (III) by solvent extraction using water-soluble H4tpaen derivatives
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The water-soluble ligand N,N,N′,N′-tetrakis[(6-carboxypyridin-2-yl)methyl]ethylenediamine (H4tpaen) and its derivatives were synthesized and evaluated for Am/Cm separation by solvent extraction. In this context, different ligands were studied for their possible use as selective back-extraction agents of actinides, especially americium, from an organic TPH phase. The solvent consisted of different extractants mixtures (DMDOHEMA/HDEHP or TODGA/TBP systems) and was preliminarily loaded with trivalent lanthanide and actinide cations. The aim of these new water-soluble agents was to strip americium or curium in an aqueous acidic phase in order to perform their mutual separation while maintaining other cations in the organic phase. A specific ligand bearing n-alkoxy groups connected to the pyridyl rings of H4tpaen showed water solubility slightly enhanced associated with efficient back-extraction properties with the possibility to perform simultaneously inter-group separation of Am (III) from Eu (III), and intra-group separation of Am(III) from Cm(III).
- Gracia, Stéphanie,Arrachart, Guilhem,Marie, Cécile,Chapron, Simon,Miguirditchian, Manuel,Pellet-Rostaing, Stéphane
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p. 5321 - 5336
(2015/07/15)
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- NOVEL WATER-SOLUBLE COMPLEXING AGENTS AND CORRESPONDING LANTHANIDE COMPLEXES
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The invention relates to complexing agents of formula (I): in which A, chrom1, chrom2 and chrom3 are as defined in the description. The invention also relates to the lanthanide complexes obtained from these complexing agents.
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Paragraph 0171
(2015/12/30)
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- Chiral probe development for circularly polarised luminescence: Comparative study of structural factors determining the degree of induced CPL with four heptacoordinate europium(III) complexes
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A series of bright, europium(iii) complexes has been prepared based on an achiral heptadentate triazacyclononane ligand bearing two strongly absorbing, coordinated aralkynyl pyridyl moieties. The binding of chiral carboxylates, including α-hydroxy acids such as lactate and mandelate, has been monitored by emission spectroscopy and is signalled by the switching on of strong circularly polarised emission. In each case, an R-chiral carboxylate gave rise to emission typical of a Δ complex, most clearly shown in the form of the ΔJ = 4 transition manifold around 700 nm. Variations in the sign and magnitude of the CPL allow the enantiomeric purity and absolute configuration of the acid to be assessed in a sample. Analysis of the relative energies of the parent aqua complexes and their stereoisomeric adducts has been aided by lifetime measurements and density functional theory calculations.
- Neil, Emily R.,Fox, Mark A.,Pal, Robert,P?lsson, Lars-Olof,O'Sullivan, Benjamin A.,Parker, David
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supporting information
p. 14937 - 14951
(2015/08/24)
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- NOVEL COMPLEXING AGENTS AND CORRESPONDING LANTHANIDE COMPLEXES
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The present invention concerns complexing agents of formula (I) in which a, b, c, chrom1, chrom2, chrom3, R3, R4 and R5 are as defined in the description. The invention also concerns lantha
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Paragraph 0201
(2014/11/27)
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- Efficient formation of luminescent lanthanide(III) complexes by solid-phase synthesis and on-resin screening
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Time-resolved luminescence measurements of luminescent lanthanide complexes have advantages in biological assays and high-throughput screening, owing to their high sensitivity. In spite of the recent advances in their energy-transfer mechanism and molecular-orbital-based computational molecular design, it is still difficult to estimate the quantum yields of new luminescent lanthanide complexes. Herein, solid-phase libraries of luminescent lanthanide complexes were prepared through amide-condensation and Pd-catalyzed coupling reactions and their luminescent properties were screened with a microplate reader. Good correlation was observed between the time-resolved luminescence intensities of the solid-phase libraries and those of the corresponding complexes that were synthesized by using liquid-phase chemistry. This method enabled the rapid and efficient development of new sensitizers for SmIII, EuIII, and TbIII luminescence. Thus, solid-phase combinatorial synthesis combined with on-resin screening led to the discovery of a wide variety of luminescent sensitizers. La confidential: Solid-phase synthesis by using amide-condensation and Pd-coupling reactions enabled the efficient development of new antenna ligands for SmIII, EuIII, and Tb III atoms for discovering a wide variety of luminescent sensitizers. Copyright
- Nakamura, Tatsuya,Mizukami, Shin,Tanaka, Miho,Kikuchi, Kazuya
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supporting information
p. 2685 - 2690
(2013/11/19)
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- Scale-up of flow-assisted synthesis of C2-symmetric chiral PyBox ligands
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A series of PyBox ligands were prepared from commercially available chelidonic acid by a multistep flow sequence using mesoreactor technology. A chloro group introduced onto the ligand scaffold was subsequently exploited to give amine derivatives ready for immobilization through microencapsulation technologies. Georg Thieme Verlag Stuttgart · New York.
- Battilocchio, Claudio,Baumann, Marcus,Baxendale, Ian R.,Biava, Mariangela,Kitching, Matthew O.,Ley, Steven V.,Martin, Rainer E.,Ohnmacht, Stephan A.,Tappin, Nicholas D. C.
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p. 635 - 647
(2012/04/17)
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- Pyridostatin analogues promote telomere dysfunction and long-term growth inhibition in human cancer cells
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The synthesis, biophysical and biological evaluation of a series of G-quadruplex interacting small molecules based on a N,N′-bis(quinolinyl) pyridine-2,6-dicarboxamide scaffold is described. The synthetic analogues were evaluated for their ability to stabilize telomeric G-quadruplex DNA, some of which showed very high stabilization potential associated with high selectivity over double-stranded DNA. The compounds exhibited growth arrest of cancer cells with detectable selectivity over normal cells. Long-time growth arrest was accompanied by senescence, where telomeric dysfunction is a predominant mechanism together with the accumulation of restricted DNA damage sites in the genome. Our data emphasize the potential of a senescence-mediated anticancer therapy through the use of G-quadruplex targeting small molecules based on the molecular framework of pyridostatin.
- Müller, Sebastian,Sanders, Deborah A.,Di Antonio, Marco,Matsis, Stephanos,Riou, Jean-Fran?ois,Rodriguez, Rapha?l,Balasubramanian, Shankar
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supporting information; experimental part
p. 6537 - 6546
(2012/09/08)
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- Effects of a halogenated G-quadruplex ligand from the pyridine dicarboxamide series on the terminal sequence of XpYp telomere in HT1080 cells
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Non-canonical four-stranded structures called G-quadruplexes can form among telomere repeats during its replication. Small molecule ligands able to interact and to stabilize G-quadruplexes were shown to disrupt the binding of essential telomeric components, such as POT1 and to trigger a telomeric dysfunction associated with a delayed growth arrest in tumor cells. We describe here the chemical synthesis and the G-quadruplex binding properties of three halogenated analogs of the 360A ligand that belongs to the 2,6 pyridine dicarboxamide series. 360A is now commonly used as a benchmark both for biophysical and cellular assays as this compound was shown to display a potent affinity and selectivity for telomeric G-quadruplex DNA over duplex DNA and to induce delayed growth inhibition in HT1080 tumor cell line. Two biophysical assays indicate that, in most cases, the presence of the halogen atom seems to slightly improve the interaction with the telomeric quadruplex. For stability reasons, the bromo derivative (360A-Br) was selected for the cellular assays. Since POT1 participates to the fine tuning of the C-strand end resection during telomere replication, we investigated the effect of 360A-Br to alter the terminal nucleotide composition of XpYp telomere in HT1080 cells using C-STELA. HT1080 cells treated for up to 24 days with 360A-Br presented some minor but significant variations of C-strand terminal nucleotide composition, also observed with a partial siRNA depletion of POT1. The relevance of these minor modifications of the telomeric C-strand resection induced by 360A-Br in HT1080 cells are discussed.
- Sidibe, Assitan,Hamon, Florian,Largy, Eric,Gomez, Dennis,Teulade-Fichou, Marie-Paule,Trentesaux, Chantal,Riou, Jean-Francois
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p. 2559 - 2568
(2013/01/15)
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- Electronic effects in 4-substituted bis(imino)pyridines and the corresponding reduced iron compounds
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A family of 4-substituted bis(imino)pyridines, 4-X-iPrPDI (4-X-iPrPDI = 2,6-(2,6-iPr2-C6H 3N=CMe)2-4-X-C5H2N; X = CF 3, tBu, Bn, NMe2), has been synthesized and the iron coordination chemistry studied. Sodium amalgam reduction of the iron dihalides (4-X-iPrPDI)FeX2 (X = Cl, Br) in the presence of excess carbon monoxide furnished the corresponding iron dicarbonyl compounds (4-X-iPrPDI)Fe(CO)2. Equilibrium mixtures of the four- and five-coordinate iron dinitrogen compounds (4-X-iPrPDI)FeN 2 and (4-X-iPrPDI)Fe(N2)2 were prepared by performing the sodium amalgam reduction of the iron dihalides under a dinitrogen atmosphere. Electrochemical and spectroscopic measurements were conducted on the free ligands and the iron derivatives to systematically evaluate the influence of each para pyridine substituent on the electronic structure of the compound.
- Darmon, Jonathan M.,Turner, Zoe R.,Lobkovsky, Emil,Chirik, Paul J.
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scheme or table
p. 2275 - 2285
(2012/06/04)
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- Ruthenium(II) sensitizers with heteroleptic tridentate chelates for dye-sensitized solar cells
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Two new for Ru: Unprecedented RuII sensitizers are coordinated by two tridentate ligands, a tricarboxyterpyridine, and a dianionic bis(pyrazolyl)pyridine derivative with an extended π-conjugated auxochrome (see picture, Rumagenta, Nblue, Ored, Fgreen, Syellow, Cgray). This new generation of thiocyanate-free RuII sensitizers offers solar conversion efficiency in dye-sensitized solar cells up to I·=10.7 %.
- Chou, Chun-Cheng,Wu, Kuan-Lin,Chi, Yun,Hu, Wei-Ping,Yu, Shuchun Joyce,Lee, Gene-Hsiang,Lin, Chi-Li,Chou, Pi-Tai
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supporting information; scheme or table
p. 2054 - 2058
(2011/04/23)
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- Modulating the photophysical properties of azamacrocyclic europium complexes with charge-transfer antenna chromophores
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Two europium complexes with bis(bipyridine) azamacrocyclic ligands featuring pendant arms with or without p-conjugated donor groups are synthesized and fully characterized by theoretical calculations and NMR spectroscopy. Their photophysical properties, i
- Bourdolle, Adrien,Allali, Mustapha,Mulatier, Jean-Christophe,Le Guennic, Boris,Zwier, Jurriaan M.,Baldeck, Patrice L.,Buenzli, Jean-Claude G.,Andraud, Chantal,Lamarque, Laurent,Maury, Olivier
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scheme or table
p. 4987 - 4999
(2011/08/04)
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- Synthesis of new enantiopure dimethyl- and diisobutyl -substituted pyridino-18-crown-6 ethers containing a halogen atom or a methoxy group at position 4 of the pyridine ring for enantiomeric recognition studies
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New enantiomerically pure dimethyl- and diisobutyl-substituted pyridino-18-crown-6 ethers containing a halogen atom or a methoxy group at position 4 of the pyridine ring [(S,S)-1, (S,S)-2, (S,S)-3, (S,S)-4] have been synthesized. A new synthetic route and
- Kupai, Jozsef,Huszthy, Peter,Szekely, Kata,Toth, Tuende,Parkanyic, Laszlo
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experimental part
p. 77 - 93
(2011/06/10)
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- Significance of interactions of BACE1-Arg235 with its ligands and design of BACE1 inhibitors with P2 pyridine scaffold
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Recently, we reported potent substrate-based pentapeptidic BACE1 inhibitors possessing a hydroxymethylcarbonyl isostere as a substrate transition-state mimic. Because these inhibitors contained some natural amino acids, we would need to improve their enzymatic stability in vivo and permeability across the blood-brain barrier, so that they become practically useful. Subsequently, non-peptidic and small-sized BACE1 inhibitors possessing a heterocyclic scaffold, 2,6-pyridenedicarboxylic, chelidamic or chelidonic moiety, at the P2 position were reported. These inhibitors were designed based on the conformer of docked inhibitor in BACE1. In this study, we discuss the role and significance of interactions between Arg235 of BACE1 and its inhibitor in BACE1 inhibitory mechanism. Moreover, we designed more potent small-sized BACE1 inhibitors with a 2,6-pyridinedicarboxylic scaffold at the P2 position, that were optimized for the interactions with Arg235 of BACE1.
- Hamada, Yoshio,Ohta, Hiroko,Miyamoto, Naoko,Sarma, Diganta,Hamada, Takashi,Nakanishi, Tomoya,Yamasaki, Moe,Yamani, Abdellah,Ishiura, Shoichi,Kiso, Yoshiaki
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scheme or table
p. 2435 - 2439
(2009/12/25)
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- Ruthenium-catalyzed asymmetric epoxidation of olefins using H 2O2, part I: Synthesis of new chiral N,N,N,-tridentate pybox and pyboxazine ligands and their ruthenium complexes
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The synthesis of chiral tridentate N,N,N-pyridine-2.6-bisoxazolines 3 (pyhox ligands) and N,N,N-pyridine-2.6-bisoxazines 4 (pyboxazine ligands) is described in detail. These novel ligands constitute a useful tool-box for the application in asymmetric catalysis. Compounds 3 and 4 are conveniently prepared by cyclization of enantiomerically pure α- or β-amino al cohols with dimethyl pyridine-2,6-dicarboximidate. The corresponding ruthenium complexes are efficient asymmetric epoxidation catalysts and have been prepared in good yield and fully char acterized by spectroscopic means. Four of these ruthenium complexes have been characterized by X-ray crystallography. For the first time the molecular structure of a pyboxazine complex (2,6-bis-[(4S)-4-phenyl-5,6- dihydro-4H-[1,3]oxazinyl]pyridine)(pyridine-2,6-dicarboxylate)ruthenium (S)-2aa, is presented.
- Tse, Man Kin,Bhor, Santosh,Klawonn, Markus,Anilkumar, Gopinathan,Jiao, Haijun,Doebler, Christian,Spannenberg, Anke,Magerlein, Wolfgang,Hugl, Herbert,Beller, Matthias
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p. 1855 - 1874
(2008/02/02)
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- Monocyclic heterocycles as kinase inhibitors
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The present invention is directed to compounds having the formula and methods for using them for the treatment of cancer.
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Page/Page column 83-84
(2008/06/13)
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- Synthesis of poly(pyridylthioether) dendrimers incorporating a Fe 2(CO)6 cluster core
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New pyridylthioether-based dendrons bearing a thiol moiety at their focal point have been prepared by a convergent synthetic approach. These dendrons were readily attached to a Fe2(CO)6 core to generate two-directional dendritic molecules incorporating an iron-carbonyl cluster.
- Chessa, Gavino,Canovese, Luciano,Visentin, Fabiano,Santo, Claudio,Seraglia, Roberta
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p. 1755 - 1763
(2007/10/03)
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- Synthesis of novel multifunctional pyridine-2,6-dicarboxylic acid derivatives
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Eleven novel multifunctional compounds with pyridine-2,6-dicarboxylic acid were synthesized by hydrolyzing of ester prepared by coupling of diethyl 4-hydroxypyridine-2,6-dicarboxylate to bis-halohydrocarbon or bis-halide. All of the new compounds were characterized by 1H NMR, MS, IR and EA.
- Yin, Xian-Hong,Tan, Min-Yu
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p. 1113 - 1119
(2007/10/03)
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- Synthesis of new Cu(II)-chelating ligand amphiphiles and their esterolytic properties in cationic micelles
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Four new tetradentate 2,6-disubstituted pyridine and tridentate 2-substituted pyridine ligands were synthesized. Two of these compounds possessed a metal ion binding subunit in the form of a 2,6-disubstituted-4-N,N′-dimethylamine pyridine moiety. Cu2+-complexes of these ligands incorporated in cetyltrimethylammonium bromide (CTABr) micelles speeded the cleavage of p-nitrophenyldiphenyl phosphate and p-nitrophenyl hexanoate at pH 7.6. On the basis of a kinetic version of Job plot analysis, a 1:1 ligand/Cu2+ stoichiometry was found to be the most active species. In CTABr micelles, the pKa values for the Cu2+-coordinated hydroxyl or pendant-CH2OH in these ligands were between 7.8 and 7.9. The metallomicellar systems displayed catalytic (turnover) behavior in the presence of excess substrates.
- Bhattacharya, Santanu,Snehalatha, Karnam,Kumar, V. Praveen
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p. 2741 - 2747
(2007/10/03)
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- Synthesis, characterization, and spectroscopic properties of three novel pentadentate copper(II) complexes related to the metalchelating inhibitors against DNA binding with HIV-EP1
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Three potentially five-coordinate peptide ligands having a pyridine and two histidine moieties, were synthesized to study their copper(II) complexation. Blue copper(II) complexes with deprotonated amide groups were isolated from methanolic solutions of the corresponding ligands with equimolar Cu(OAc) 2·H2O. The structures of two of them were determined by X-ray crystallography. The Cu is coordinated to five nitrogen atoms in both complexes; the coordination geometry was a distorted square pyramid in one, and intermediate between a square pyramid and trigonal bipyramid in the other. EPR spectra in frozen methanol solutions at 77 K as well as visible absorption spectra indicate that the distortion of the geometry around the copper is reduced by the introduction of an alkylamine substituent on the pyridine of the ligand and that the substituted complexes distort toward trigonal bipyramidal geometry compared to the unsubstituted one in solution. The Royal Society of Chemistry 2001.
- Kurosaki, Hiromasa,Sharma, Rakesh Kumar,Aoki, Sachiko,Inoue, Teruhiko,Okamoto, Yoshinari,Sugiura, Yukio,Doi, Mitsunobu,Ishida, Toshimasa,Otsuka, Masami,Goto, Masafumi
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p. 441 - 447
(2007/10/03)
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- A new versatile methodology for the synthesis of 4-halogenated-6-diethylcarbamoylpyridine-2-carboxylic acids
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Convenient syntheses of dipicolinic or chelidamic acid derivatives including 4-X-6-diethylcarbamoyl-pyridine-2-carboxylic acid (X=H, Cl, Br) and 4-chloro-6-(3-oxo-3-phenylpropionyl)pyridine-2-carboxylic acid methyl ester are described. These compounds are important synthons for the synthesis of non-symmetric tridentate aromatic chelating agents as well as for the design of ditopic ligands targeted for the elaboration of functional dimetallic helicates.
- Chauvin, Anne-Sophie,Tripier, Rapha?l,Bünzli, Jean-Claude G.
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p. 3089 - 3091
(2007/10/03)
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- Substituted pyridino pentaazamacrocyle complexes having superoxide dismutase activity
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The present invention relates to compounds which are effective as catalysts for dismutating superoxide and, more particularly, the manganese or iron complexes of substituted, unsaturated heterocyclic pentaazacyclopentadecane ligands which catalytically di
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- Effect of a halogenide substituent on the stability and photophysical properties of lanthanide triple-stranded helicates with ditopic ligands derived from bis(benzimidazolyl)pyridine
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Bis {1-ethyl-2-[6-(N,N-diethylcarbamoyl)-4-halogenopyridin-2-yl]benzimidazol-5-yl} methane (halogeno = chloro, LE; bromo, LF) have been synthesized as ditopic receptors for the development of lanthanide-containing helicates able to couple with biological material and to test the influence of the halogeno substituent on the wrapping process, the structure of the resulting dimetallic edifices, and the photophysical properties of the encapsulated ions. The stability of the [Eu2(L)3]6+ helicates, as determined by NMR competitive titrations, decreases by respectively one (LF) and three (LE) orders of magnitude compared to the value found for the unsubstituted ligand (LB) although it remains large, log β23 = 23.8 (LF) and 21.8 (LE) in acetonitrile. The [Ln2(LE)3]6+ helicates are shown to be isostructural in acetonitrile over the lanthanide series (Pr to Yb) and the crystal structure of [Tb2(LB)3]6+ appears to be a good model for their solution structure, as demonstrated by paramagnetic NMR measurements (lanthanide induced shift method) and relaxation time determination. Ligand LE appears to be a fair sensitiser of EuIII, the quantum yield of [Eu2(LE)3]6+ being 25% larger than that found for [Eu2(LB)3]6+, but the ligand 3ππ* state and Tb(5D4) excited level are in resonance, which limits the sensitisation of TbIII. High resolution luminescence spectra of [Eu2(LE)3]6+, both in solution and in the solid state, are presented and discussed in terms of site symmetry and vibronic coupling mechanisms. The Royal Society of Chemistry 2000.
- Iglesias, Carlos Platas,Elhabiri, Mourad,Hollenstein, Marcel,Buenzli, Jean-Claude G.,Piguet, Claude
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p. 2031 - 2043
(2007/10/03)
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- Synthesis and structure-activity relationships of phenylenebis(methylene)-linked bis-azamacrocycles that inhibit HIV-1 and HIV- 2 replication by antagonism of the chemokine receptor CXCR4
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Bis-tetraazamacrocycles such as the bicyclam AMD3100 are a class of potent and selective anti-HIV-1 and HIV-2 agents that inhibit virus replication by binding to the chemokine receptor CXCR4, the co-receptor for entry of X4 viruses. With the aim of optimi
- Bridger, Gary J.,Skerlj, Renato T.,Padmanabhan, Sreenivasan,Martellucci, Stephen A.,Henson, Geoffrey W.,Struyf, Sofie,Witvrouw, Myriam,Schols, Dominique,De Clercq, Erik
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p. 3971 - 3981
(2007/10/03)
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- Substituted 2-aminopyridines as inhibitors of nitric oxide synthase
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Substituted 2-aminopyridine compounds of Formula (I) and pharmaceutically acceptable salts which have been found useful in the treatment of nitric oxide synthase mediated diseases and disorders. STR1
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- Synthesis of Some Copper(II)-Chelating (Dialkylamino)pyridine Amphiphiles and Evaluation of Their Esterolytic Capacities in Cationic Micellar Media
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Three new (dialkylamino)pyridine (DAAP)-based ligand amphiphiles 3-5 have been synthesized. All of the compounds possess a metal ion binding subunit in the form of a 2,6-disubstituted DAAP moiety. In addition, at least one ortho-CH2OH substitue
- Bhattacharya, Santanu,Snehalatha, Karnam,George, Shaji K.
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- Design and synthesis of complementary components for the formation of self-assembled supramolecular rigid rods
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The complementary components AP2 and AU2, resulting respectively from the linking of diacylaminopyridine and uracil derivatives to an anthracenic core, have been designed in order to self-assemble, through hydrogen bonding, into polymeric supramolecular rigid rods (AP2, AU2)(n). The synthesis of these compounds is reported.
- Kotera, Mitsu,Lehn, Jean-Marie,Vigneron, Jean-Pierre
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p. 1953 - 1972
(2007/10/02)
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- A Novel Reagent for Labelling Macromolecules with Intensely Luminescent Lanthanide Complexes
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A novel bifunctional chelator, 4-iodoacetamidodipicolinic acid, has been synthesized in three steps starting with chelidamic acid, and used to prepare protein conjugates that form stable and intensely luminescent complexes with Tb(III) and Eu(III).The excited state lifetime of Tb(III) complexes with this reagent was 1.25 ms, permitting its use for ultrasensitive time-resolved luminescence assays.
- Lamture, Jagannath B.,Wensel, Theodore G.
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p. 4141 - 4144
(2007/10/02)
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- Cation Complexing Properties of Synthetic Macrocyclic Polyether-Diester Ligands Containing the Pyridine Subcyclic Unit
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Ten new macrocyclic polyether-diester compounds containing a pyridine subcyclic unit substituted in the 4 position with chloro or methoxy groups have been prepared.These compounds along with their unsubstituted pyridine analogues form strong complexes wit
- Bradshaw, J. S.,Maas, G. E.,Lamb, J. D.,Izatt, R. M.,Christensen J. J.
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p. 467 - 474
(2007/10/02)
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- Pyridine dioxamic acids and esters
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Novel compounds of formula 1 SPC1 And SPC2 Are useful in the prophylactic treatment of sensitized humans and animals for allergy and all anaphylactic reactions of a reagin or non-reagin mediated nature. The compounds are formulated with pharmaceutical carriers for oral, parenteral, inhalation or rectal means of administration.
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