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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.
31

Synthesis of DNA Minor Groove Binders and Investigation of Biophysical Properties

Liu, Meng-Chi 18 January 2012 (has links)
I am interested in the design of DNA binding ligands which are including DNA minor groove binders and G-quadruplex stabilizing agents. Certain natural products, distamycin and belomycin are considered as models for designing new DNA binding agents. A variety of DNA binding ligands were synthesized and accordingly characterized by different bioassays. In the series of azo-pyrrole-polyamide, it showed slight DNA binding affinity but has the properties of DNA photo-cleavage and recognition of mixed sequence. The thiophene series showed strong binding ability for duplex DNA. Bithiophene series showed a remarkable binding affinity to duplex DNA which is compatible to natural products netropsin and distamycin. The pyridodicarboxamide series remain intramolecular hydrogen bonding with poor preferences for duplexes DNA even though they stabilized quadruplex DNA. The bithiophene-bipyrimidine compound binds to specific hexanucleotide sequence 5¡¦-AAGCTT-3¡¦ and acts as an unfused quadruplex stabilization ligand. In the quinoline series, the combination of quinoline and methylpyrrole polyamide proves the attenuation effect for quadruplexes stabilization which provides a novel strategy for development of quadruplex binding logands. In this study, several series of small molecules for DNA binding have been successfully synthesized and proved to interact with DNA secondary structures according to the particular properties of themselves.
32

Hydrothermal synthesis of lithium iron phosphate with Fe(III) as precursor using pyrrole as an efficient reducing agent

Chen, Wen-jing 03 August 2012 (has links)
Lithium iron phosphate (LiFePO4) is prepared by hydrothermal process using Fe(III) as precursor and pyrrole as an efficient reducing agent. The Fe(III) precursor in the system reacts with pyrrole to generate polypyrrole (PPy) and reduce Fe(III) to Fe(II). The different molar ratio Fe(III) polymerize different content of PPy and PPy can also be a carbon source for further calcination. The structural and morphological properties of LiFePO4 powder were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and a transmission electron microscope (TEM). The XRD and TEM results demonstrate that LiFePO4 powder has an orthorhombic olivine-type structure with a space group of Pnma. The SEM and TEM results show that the particle size of LiFePO4 is around 200 nm and a layer of carbon coats on LiFePO4. The chemical composition of the LiFePO4 powder was characterized by elemental analysis (EA) and inductively coupled plasma/mass spectroscopy (ICP/MS). Raman and X-ray photoelectron spectroscopy (XPS) results indicate that pyrrole as a reducing agent reduces and prevents the formation of Fe(III) impurity and the resulting PPy plays a role as carbon source. Among the synthesized cathode materials, LiFePO4 synthesized using 5% molar ratio of Fe(III) and subsequent calcinations of 600 ¢XC shows the best electrochemical property with an discharge capacity of 160 mAhg−1 close to its theoretical capacity 170 mAh g−1 at 0.2 C rate. Using 10% molar ratio of Fe(III), and the discharge capacity of LiFePO4 at 10 C rate reaches 106 mAhg−1.
33

Synthesis of new DNA-Binding Agents with polyamide moiety

Lai, Ming-Chi 05 July 2003 (has links)
Synthetic netropsin analogs of the thiophene and pyridine, induce the netropsin analogs binding DNA from A-T base pair change to G-C base pair. Moreover, dendritic electrostatic groups have bulky conformation, which induce the netropsin analogs binding DNA to major groove.
34

Exploring Metal-Ligand Interactions of Pyrrole Based Pincer Ligands

Maaß, Christian 16 October 2013 (has links)
No description available.
35

Towards a Metal-catalyzed Annulation Route to Pyridines and N-Hydroxy Pyrroles

Whitmore, Kenneth M. 27 March 2012 (has links)
Despite progress in the metal-catalyzed synthesis of aromatic heterocycles, annulation routes towards 6-membered heterocycles remain underdeveloped. Specifically, routes towards pyridines are rare in spite of the prevalence of this moiety in novel drug candidates. Our initial efforts towards pyridines featured oximes as competent nucleophiles in the intramolecular, 6-exo dig annulation of alkynes using Brønsted acid catalysis. Two of the oxidation states required for subsequent aromatization are contained within the oxime via loss of water. An extension of this chemistry is presented and discussed, and involves the intramolecular metal-catalyzed 6-endo dig annulation of analagous alkynyl-oximes. Additionally, the discovery of a 5-exo dig annulation of related systems is discussed.
36

Novel carbene complexes with pyrrole ligands

Olivier, Andrew John 24 February 2006 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc (Chemistry))--University of Pretoria, 2006. / Chemistry / unrestricted
37

Towards a Metal-catalyzed Annulation Route to Pyridines and N-Hydroxy Pyrroles

Whitmore, Kenneth M. January 2012 (has links)
Despite progress in the metal-catalyzed synthesis of aromatic heterocycles, annulation routes towards 6-membered heterocycles remain underdeveloped. Specifically, routes towards pyridines are rare in spite of the prevalence of this moiety in novel drug candidates. Our initial efforts towards pyridines featured oximes as competent nucleophiles in the intramolecular, 6-exo dig annulation of alkynes using Brønsted acid catalysis. Two of the oxidation states required for subsequent aromatization are contained within the oxime via loss of water. An extension of this chemistry is presented and discussed, and involves the intramolecular metal-catalyzed 6-endo dig annulation of analagous alkynyl-oximes. Additionally, the discovery of a 5-exo dig annulation of related systems is discussed.
38

Synthesis and Biological Evaluation of Pyrrole-Imidazole Polyamide Probes for Visualization of Telomeres / テロメアを可視化するピロール・イミダゾールポリアミドプローブの合成と生物学的評価

Kawamoto, Yusuke 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20929号 / 理博第4381号 / 新制||理||1630(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 杉山 弘, 教授 三木 邦夫, 教授 秋山 芳展 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
39

Studies on Subporphyrins and Their Analogues / サブポルフィリンおよびその類縁体に関する研究

Yoshida, Kota 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20951号 / 理博第4403号 / 新制||理||1632(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 大須賀 篤弘, 教授 丸岡 啓二, 教授 依光 英樹 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
40

Synthesis of Early Transition Metal Complexes Supported by Pyrrolyl and Indolyl Based Ligands

Yeisley, Christopher R. 14 June 2013 (has links)
No description available.

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