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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Oxidation of the ruthenium complexes containing the diphosphonic acid substituted 2,2¡¦-bipyridine ligand

Lin, Cheng-chih 05 September 2005 (has links)
none
2

Calix[4]arènes fonctionnels pour ancrage sur polymère naturel et antennisation par le tripeptide RGD préparé par synthèse convergente

Engrand, Philippe Regnouf de Vains, Jean-Bernard. January 2008 (has links) (PDF)
Thèse de doctorat : Chimie et Physico-Chimie Moléculaires : Nancy 1 : 2008. / Titre provenant de l'écran-titre.
3

Some chiroptical effects on the photophysics and photochemistry of tris(bipyridine)ruthenium(II) ions in solution

Sparks, Robert Henry January 1979 (has links)
The photoracemization of Ru(bipy)₃⁺⁺ in aqueous solution was studied. Quenching studies show the involvement of the (CT)³ Ru(bipy)₃⁺⁺ in the mechanism of racemization and the low quantum yield (2.9 x 10⁻⁴) shows that this state is asymmetric. Quenching studies show no increase of racemization rate for Ru(I) or (III) species. The temperature dependence gives evidence for a dissociative racemization mechanism. Quenching with Co(acac)₃ shows chiroselective electron transfer as measured by the resulting photochemistry. / Science, Faculty of / Chemistry, Department of / Graduate
4

A new type of chiral bipyridine: synthesis and application in asymmetric catalytic cyclopropanation.

January 1999 (has links)
by Wong Hei Lam Harry. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 60-67). / Abstract also in Chinese. / Library's copy: Copy 2 imperfect, p. 60-63 missing. / Table of Contents --- p.i / Acknowledgments --- p.iii / Abbreviations --- p.iv / Abstract --- p.v / Abstract (Chinese) --- p.vi / Chapter CHAPTER I --- GENERAL INTRODUCTION / Chapter 1.1.1 --- Different biological activities of enantiomers --- p.1 / Chapter 1.1.2 --- Approach to enantiomerically pure compounds --- p.3 / Chapter 1.1.3 --- Principle of asymmetric synthesis --- p.4 / Chapter 1.1.4 --- Asymmetric catalysis and chiral catalyst --- p.5 / Chapter 1.2.1 --- Asymmetric cyclopropanation: general introduction --- p.6 / Chapter 1.2.2 --- Asymmetric cyclopropanation: initial studies --- p.8 / Chapter 1.2.3 --- Development of c2-symmetric semicorrin and its derivatives --- p.10 / Chapter 1.2.4 --- Bisoxazolines --- p.12 / Chapter 1.2.5 --- Tridentate N donor ligands --- p.13 / Chapter 1.2.6 --- "2,2'-Bipyridines" --- p.14 / Chapter 1.2.7 --- Chiral metalloporphyrin catalyst --- p.15 / Chapter 1.2.8 --- Intramolecular asymmetric cyclopropanation --- p.16 / Chapter CHAPTER II --- DESIGN AND SYNTHESIS OF CHIRAL LIGANDS / Chapter 2.1 --- Development of atropisomeric biaryls --- p.19 / Chapter 2.2 --- "Chiral 2,2'-bipyridine ligands" --- p.19 / Chapter 2.3 --- Design of chiral ligands --- p.22 / Chapter 2.4 --- Synthesis of target ligands: synthetic strategy --- p.22 / Chapter 2.5 --- Attempted synthesis of target ligands via cross-coupling reaction --- p.22
5

Synthesis and structural studies of metallacycles.

January 1994 (has links)
Kathleen Shuk Man Poon. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 93-94). / Abbreviations --- p.v / Lists of Figures --- p.vi / Lists of Schemes --- p.vii / Lists of Tables --- p.viii / Part I / Chapter Chapter 1 --- Introduction --- p.2 / Chapter 1.1 --- Thermal stability of metallacycles --- p.2 / Chapter 1.2 --- General Synthetic methods of Metallacycle --- p.5 / Chapter 1.3 --- Objective of this work --- p.6 / Chapter 1.4 --- Features of Ligands --- p.6 / Chapter 1.5 --- References --- p.10 / Chapter Chapter 2 --- Synthesis of Transfer Reagents --- p.11 / Chapter 2.1 --- Brief Survey of various Transfer Reagents --- p.11 / Chapter 2.2 --- Introduction to metallation reaction --- p.13 / Chapter 2.3 --- Result and Discussion --- p.16 / Chapter 2.3.1 --- Lithiation and Derivatization of Ligand --- p.16 / Chapter 2.3.2 --- Charge Migration --- p.18 / Chapter 2.3.3 --- Characterization of compounds --- p.23 / Chapter 2.4 --- Experimental --- p.27 / Chapter 2.5 --- References --- p.33 / Chapter Chapter 3 --- Synthesis of Metallacycles --- p.35 / Section I --- p.35 / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.2 --- Results and Discussion --- p.36 / Chapter 3.2.1 --- Synthesis of Metallacycles of Group 14 elements --- p.36 / Chapter 3.2.2 --- Characterization of Group 14 metallacycles --- p.42 / Chapter 3.2.3 --- Experimental --- p.57 / Section II --- p.64 / Chapter 3.3 --- Introduction --- p.64 / Chapter 3.4 --- Result and Discussion --- p.65 / Chapter 3.4.1 --- Synthesis of Metallacycles of Group 4 elements --- p.65 / Chapter 3.4.2 --- Experimental --- p.68 / Chapter 3.5 --- Attempted synthesis of Group 12 Metallacycles --- p.70 / Chapter 3.5.1 --- Results and Discussion --- p.70 / Chapter 3.5.2 --- Experimental --- p.71 / Chapter 3.6 --- References --- p.73 / Part II --- p.75 / Chapter Chapter 4 --- Synthesis of Bimetallic Complex --- p.76 / Chapter 4.1 --- Brief Review on Bimetallic Complexes --- p.76 / Chapter 4.2 --- Results and Discussion --- p.80 / Chapter 4.2.1 --- Synthesis of bimetallic complexes --- p.80 / Chapter 4.2.2 --- Characterization of bimetallic complexes --- p.87 / Chapter 4.2.3 --- Experimental --- p.90 / Chapter 4.3 --- References --- p.93 / Appendix I General Experimental Procedure --- p.95
6

Construction d'entités luminescentes autour des unités thiophènes, bipyridines et boradiazaindacènes

Goeb, Sébastien Ziessel, Raymond. De Nicola, Antoinette. January 2007 (has links) (PDF)
Thèse doctorat : Chimie : Strasbourg 1 : 2006. / Titre provenant de l'écran-titre. Notes bibliogr.
7

SYNTHESIS OF BIPYRIDINE-DERIVED LIGANDS FOR DNA BINDING AND SHAPE SWITCHING

LI, XUE 08 September 2009 (has links)
The objective of this project is synthesizing bipyridine-derived ligands in order to study DNA conformational bending. The synthesis of bipyridine derivatives has been investigated. 6,6’-Dibromo-2,2’- bipyridine and small scale of 6,6’-diformyl-2,2’-bipyridine have been successfully synthesized in the laboratory. The synthesis of large amount of a direct precursor to 6,6’-diformyl-2,2’- bipyridine in an multiple step way has been achieved. The synthesis of mono functionalized pyrene derivatives and of 1,6-dissymmetrically functionalized pyrene derivatives has been heavily studied. Successfully methods have been reported in this thesis. The complete assembly of bipyridine and pyrene units into the final ligands and their model has also been studied. Palladium borylation and Suzuki-Miyaura cross-coupling have been used to successfully connect the bipyridine with pyrene units. In addition to Suzuki-Miyaura methodology, the direct coupling of N,N’-dioxide-2,2’- bipyridine with aromatic bromides under palladium catalysis has been investigated. This method could be an alternative way to access to mono-substituted 6-bipyridines, symmetrically or even asymmetrically 6,6’-disubstituted-2,2’-bipyridine derivatives. / Thesis (Master, Chemistry) -- Queen's University, 2009-09-06 01:06:41.646
8

Modulation der Helix-Bündel-Bildung eines Bipyridin-funktionalisierten peptidischen Ionenkanals durch Komplexierung von Ni(II)

Pilz, Claudia Sabine January 2007 (has links)
Regensburg, Univ., Diss., 2007
9

Contribution à la réalisation et à l'étude de couches minces par dépôt chimique en phase vapeur à partir du complexe bis 2.2'-bipyridine silicium.

Pouvreau, Philippe, January 1900 (has links)
Th. doct.-ing.--Physico-chim. des matér.--Toulouse--I.N.P., 1978. N°: 19.
10

Synthesis and bio-applications of luminescent iridium (III) and ruthenium (II) bipyridine complexes

Wang, Haitao 24 August 2020 (has links)
This thesis is based on the past three years of research work including synthesis, characterization of three series of iridium(III) complexes and one series of ruthenium(II) complexes, and their comparative bio-applications of DNA-binding, cell morphology, cytotoxicity, mitochondrial membrane potential, cellular uptake and distribution. Chapter 1 introduces the background and recent studies of transition-metal complexes as biosensors and anti-tumor medicines. Their structure related properties of cytotoxicities, cellular uptake and distributions were also discussed. In chapter 2, five iridium(III) complexes Ir4: [Ir(4-mpp)2DPPZ]+, Ir7: [Ir(4-mpp)2BDPPZ]+, Ir8: [Ir(4-mpp)2MDPPZ]+, Ir115: [Ir(pp)2DBDPPZ]+ and Ir139: [Ir(dpapp)2DBDPPZ]+ were synthesized and characterized. The crystals of complex Ir139 were successfully cultured and analyzed by X-ray crystallography. The HOMO and LUMO energy gaps of complexes Ir4, Ir7 and Ir8 were obtained. The smaller the energy gap is the larger the Stokes shift will be. The DNA binding properties of Ir4, Ir7 and Ir8 were studied to acquire their binding constants and quenching constants. All the five complexes were cultured with hepatocellular carcinoma cell (hep-G2) in different concentrations for cell morphologies and MTT assays. The IC50 values were calculated and the structure-activity relationship (SAR) was discussed. Properties of Ir115 and Ir139 for photodynamic therapy under the visible light were studied, and moderate light-enhanced cytotoxicities were discovered. The live and dead cell assay and mitochondrial transmembrane potential (ΔΨM) testing were performed and a similar cytotoxicity order to IC50 values was obtained. Some interesting interactions between complex and calcein or propidium iodide (PI) dye were observed and discussed. Cellular uptake and distribution assay showed that the fluorescence of iridium complex was closely related to its toxicity. The obvious cellular uptake at 4 ℃ indicated that all the complexes could transfer into cell through a passive transport mode of facilitated diffusion without the consumption of ATP. The greatest change in uptake intensity of Ir115 implied that the ATP could assist the transport of Ir115 at 37.5 ℃. The efficiency of uptake and distribution of complexes in paraformaldehyde (PFA) fixed cells was found to be strictly related to their size and the hydrophobicity. The rigidity of dipyrido[3,2-a:2',3'-c]phenazine based bipyridine ligands in this chapter contributed to the main cytotoxcities of those iridium complexes. Most of the iridium complexes in chapter 2 have similar structures to their classic ruthenium analogues while their activities have largely improved due to the higher cellular uptake and more biocompatibility. Chapter 3 presented five iridium complexes with rotatable 1H-imidazo [4,5-f] [1,10] (phenanthroline) based bipyridine ligands, which are Ir79: [Ir(pp)2MTPIP]+, Ir80: [Ir(pp)2EIPP]+, Ir116: [Ir(piq)2APIP]+, Ir119: [Ir(piq)2PPIP]+ and Ir134: [Ir(iqdpba)2PPIP]+. Cell morphology and proliferation assay, MTT assay indicated that most of them were not quite toxic for hep-G2 cell lines except for Ir116 which contained an amino group and was assumed to be very active to the carboxyl group in the protein residues in cells. Under the irradiation of visible light, Ir80 and the Ir119 were found to be quite photo-toxic with the light IC50 value of 8.08 μM and 6.14 μM respectively. They could become the potential candidates for the promising drugs of photo-dynamic therapy. The cytotoxicities of those five complexes were further investigated by the live and dead assay using calcein AM (acetoxymethyl) and propidium iodide (PI) double stain method. JC-1 aggregates observation and analysis in the mitochondrial transmembrane potential (ΔΨM) testing proved the lower cytotoxicities of those five complexes than those in chapter 2. Fluorescence and cytotoxicity relationship (FCR) was also uncovered in chapter 3 in which the stronger macromolecular binding to complex could lead to its higher fluorescence intensity. Without the metabolic activity and the assistance of ATP at low temperature of 4 ℃, little Ir80 and Ir134 were found in cells, and the moderate uptake for Ir79 and higher volume of Ir116 and Ir119 were detected. A novel strategy of cold-shock enhanced cellular uptake pathway was discovered in Ir119 and its cold-shock caused cytotoxicity would be further evaluated. The volumes of uptake for those complexes in paraformaldehyde fixed cells were all very low due to their higher hydrophilicity and lower structural rigidity than those in chapter 2. Chapter 4 reported the investigation of six iridium complexes of Ir105: [Ir(4-mpp)2CDYP]+, Ir107: [Ir(piq)2CDYP]+, Ir108: [Ir(3-mpp)2CDYP]+, Ir123: [Ir(4-mpp)2CDYMB]+, Ir125: [Ir(piq)2CDYMB]+ and Ir133: [Ir(dpapp)2CDYMB]+ with rotatable 5H-cyclopenta[2,1-b:3,4-b']dipyridin Schiff-base ligands. Most of them were rather toxic to hep-G2 cell lines from the MTT assay, cell morphology and proliferation assay due to the Schiff-base N^N ligands. Those rotatable Schiff-base ligands seemed to have more cytotoxicity than the flexible 1H-imidazo[4, 5-f] [1, 10](phenanthroline) ligands in chapter 3. The planar and rigid structure of piq C^N ligands in Ir107 and Ir125 were supposed to contribute to the highest cytotoxicity in chapter 4. The dead (red PI) to live (green calcein) cell area ratios and the ΔΨM assay were in accordance with the cytotoxocity sequence in MTT assay. Most of the complexes in chapter 4 demonstrated characteristics of one kind of programmed cell death (PCD), namely apoptosis and the typical features of another cell death mode of oncosis including cellular dwelling and cytoplasm vacuolation have been discovered from Hep-G2 cell lines in the incubation with Ir107. The JC-1 aggregates have disappeared when the two most toxic complexes Ir107 and Ir125 were cultured with the cells at 5 μmol/L, indicating the ΔΨM lost repidly under the damage of iridium complexes. All the complexes were distributed in the cellular nuclei when the incubation time reached 120 minutes at the concentration of 20 and 40 μmol/L. The positive correlation in the fluorescence and cytotoxicity relationship (FCR) were also discovered in chapter 4. The luminescence intensity sequence of the complexes from the cellular uptake and distribution has almost the same order as the previous toxicity results. The two most toxic complexes of Ir107 and Ir125 were found to have the two highest fluorescent intensities inside cells at 4 ℃. Most complexes in this chapter could easily distribute in the fixed cellular nuclei except for Ir125 and Ir133 owing to their large and hydrophobic structures. Generally, the uptake of complexes in paraformaldehyde fixed cells was higher than the live cells at 4 ℃ according to their passive transport mode. Although the simple Schiff base ligands of CDYP and CDYMB in this chapter were rotatable and flexible similar to the 1H-imidazo[4, 5-f][1, 10](phenanthroline) based bipyridine ligands in chapter 3, the cytotoxicities of complexes were much higher than those in chapter 3. The former chapters implied that effective uptake of complexes in nuclei were the results of the cytotoxicities which damaged the integrity of nuclear envelope and leaked into the nucleoplasm. We assumed that there could be another explanation in chapter 4 that the complexes transferred into the nuclei through the nuclear pore on the nuclear envelope and accumulated in the nucleolus, and therefore, triggered the apoptosis of cells. This kind of evidence was discovered for the two most toxic complexes Ir107 and Ir125 that could enter into cellular nuclei when the cell looked quite healthy. There would be another possiblilty that the Schiff base could interrupt the function of intracellular hydrolase enzymes. Chapter 5 compared the properties of five ruthenium(II) complexes of Ru2: [Ru(bpy)2DBDPPZ]2+, Ru7: [Ru(bpy)2MTPIP]2+, Ru8: [Ru(bpy)2EIPP]2+, Ru15: [Ru(phen)2BPDC]2+ and Ru24: [Ru(phen)2CDYMB]2+ with the ligand DBDPPZ from chapter 2, MTPIP and EIPP from chapter 3, CDYMB from chapter 4 and BPDC with two carboxyl groups. Those two positively charged ruthenium complexes indicated very low cytotoxicities from the cell morphology assay and MTT assay. No typical features of cellular apoptosis such as round and shrank cells were observed. However, the light IC50 value of Ru8 was excitingly obtained to be 2.33 μM upon the irradiation of 465 nm which was found to be one of the most promising drugs for photodynamic therapy (PDT) in his thesis. Charge and property relationship (CPR) was discovered to be the most decisive factor in the cytotoxicities of iridium and ruthenium complexes in this thesis which was also supported by a few of the independent literature papers mentioning high cytotoxicity of one positively charged ruthenium complex or low toxicity of two positively charged iridium complex. The DBDPPZ and CDYMB ligands in the ruthenium complexes Ru2 and Ru24 did not add into their cytotoxicity but those ligands greatly enhanced the toxicities of iridium complexes. The calculation of both area and number ratios of dead to live cells stained by the PI and calcein dyes indicated the lowest dark cytotoxicity among the ruthenium complexes could be Ru8 while the Ru24 and Ru7 were more toxic than others. Active JC-1 aggregates were maintained in the cell mitochondria and did not greatly diminish with the increasing concentration of ruthenium complexes. The two positive charges were found to play the important role in the poor cellular uptake of all the ruthenium complexes and the large size of phen ligand further prevented the uptake of Ru24 and reduced its toxicity. The Ru2, Ru7 and Ru8 were found to distribute in fixed cells with much higher luminescence intensities than their corresponding iridium complexes of Ir115, Ir79 and Ir80 with the same N^N ligand respectively which were assigned to be the two positive charges in those ruthenium complexes. The facilitated diffusion was found to be the main passive transport for the five ruthenium complexes in HepG2 cells at 4 ℃ when the ATP functions were considered to be largely inhibited. The low temperature cellular uptake has the similar trend of the cytotoxicities of the five complexes, indicating the structures of complexes were decisive in the process of facilitated diffusion. The enormous difference of cellular uptake and distribution in the fixes cells remind us the normal protocol before the cell-image pictures of fluorescence inverse microscopes (FIM) or confocal laser scanning microscope (CLSM) should be cancelled or very cautiously handled when the luminescent metal complexes were applied. In chapter 6, the further structure-activity relationship (SAR) was discussed based on the different C^N, N^N ligands and metal cores from the previous chapters. The overall research scheme, results and significance were summarized. Highlights were listed and future research plan was also proposed. At last, Chapter 7 described briefly the experiment protocols and supplementary information for the former chapters.

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