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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.
11

The interaction of 9-aminocridines with native DNA / Garth Boehm

Boehm, Garth January 1981 (has links)
Typescript (photocopy) / v, 184 leaves : ill. ; 30 cm / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--Dept. of Physical and Inorganic Chemistry, University of Adelaide, 1982
12

Nuwe ouraat en karbeenkomplekse van goud(I) en goud(III): bereiding, karakterisering en reaktiwiteit.

08 August 2012 (has links)
D.Sc. / This study involves the preparation and characterization of new amino(thio) carbene complexes of gold(I) and gold(III). In addition the reactivity of bis(thiazolyl) aurate and the above mentioned carbene complexes are also described. Various thiazolyllithium reagents reacted with [AuCl(tht)] to yield bis(thiazolyl) aurate complexes of gold(I) which were isolated in crystalline form. These crystals contained solvent of crystallization and no structural determination of these aurates were possible. The latter compounds readily reacted with elemental sulphur by insertion of a sulphur atom into one of the Au-C bonds thereof Subsequent reaction with one molar equivalent of CF 3S03CH3 or CF3SO3H produced either carbene, [Au(CNRYS)(SC=NY§)] (Y = CCH 3=CH, C4H6; R = H, CH3), or thione, [Au(S=h‘TRY)(C=NYS)], complexes of gold(I) which spontaneously decomposed into gold(I) polymers ([Au(C=NYS)]. or [Au(S&=NY)].) and organic products (C=NYS or S=CNRYS). In an attempt to isolate the above-mentioned carbene or thione complexes bis(thiazolyl) aurate complexes were treated with two molar equivalents of CF3S03CH3 or CF3SO3H after sulphur insertion. Rather than the expected mixed carbene thione complexes, [Au(elsTRY§)(S=eNRY§)]CF 3S03, homoleptic rearrangement produced bis(carbene) complexes of gold(I) with unexpected counterions (Cl instead of CF 3SO3). Reaction of lithiated mercaptobenzothiazole with [AuCl(tht)] yielded a bis(thiolate) complex of gold(I), [Au(SC=NC 6H4 S-0)2]Li. Alkylation or protonation of this modified aurate complex resulted in the formation of gold polymers, [Au(S=NC 6H4 -0)]„, and organic products, S=§NRC6H4§-o, R=H, CH3 ). Oxidative addition of halogens to bis(thiazolyl) aurate complexes produced no isolable organometallic complexes. [AuC1 1]Li probably formed after repetitive oxidation addition (C1 2) and reductive elimination reaction (2-chlorothiazole). However, oxidation of these aurate complexes with SOC12 limited the reaction to one oxidative addition and one reductive elimination step to produce [AuCl(CNHYS)] (Y=CCH 3=CH, C6H4) after acidification. Reaction of the neutral mono(carbene) complex [Au(CNCCH 3=CHS)(C=NCCH3=CHS)] with C12, Br2 or 12 produced carbene complexes of gold(I), [AuX(6NHCCH 3=CH§)] (X=C1, Br, I), after reductive elimination of 2-halogeno-4-methylthiazole. Cationic bis(thiazolinylidene) complexes of gold(I) react readily with C1 2 and 12 to produce stable Ms(carbene) complexes of gold(III). However, oxidative addition on the same carbene complex by I2 is followed by a novel reductive elimination of (ICNii)cF SO to produce carbene complexes of gold(I), [AuI(CMN7- TTA )]. Alkylation (CF3SO3CH3) of 4-methylthiazole, bensothiazole and methylimidazole, followed by deprotonation (BuLi) produced free carbenes. These carbenes were trapped by reaction with [AuCl(tht)] to form carbene-chloro complexes of gold(I). Chloro(1,3- dimethylimidazolinylidene)gold(I) react readily with NaN 3 or AgNO3 to yield [AuX(CNCH3CH=CH1:TCH3)] (X = N3 or NO3 ). As part of this study the structures of several carbene complexes were determined, including five carbene complexes of gold(I) and one carbene complex of gold(III). Au-C bond lengths of between 1.92-2.13A were found with the largest Au-C separation in the carbene complex of gold(III), [Au(aNCH3CH=CHNCH3)2]CF3S03 . Certain complexes of gold(I) exhibit interesting Au...Au interactions (3.19-3.51A) resulting in the aggregation of gold atoms to form dimers and chains of gold(I) atoms. The structures of two related complexes of iron were also determined to investigate the effect of protonation on a neutral carbene precursor, [Fe(CO) 2Cp(C=CHCH=NNPh)], to form the cationic carbene complex, [Fe(C0) 2Cp(aCH=CHNHI:IPh)JCF3S03. Small changes in bond lengths and angles resulted upon carbene formation.
13

Preparation and X-ray analysis of hexamethylenetetramine oxide and its acid adducts.

January 1977 (has links)
Thesis (M.Phil.)--Chinese University of Hong Kong. / Bibliography: leaves 88-90.
14

High resolution spectroscopy of aminoborane and niobium nitride

Lyne, Michael Peter January 1987 (has links)
The infrared spectrum of aminoborane (NH₂BH₂) was recorded by a Fourier transform interferometer and the 1550-1750 cm⁻¹ region of the spectrum was rotationally analyzed by a new search/match algorithm based on ground state combination differences. Sub-bands from four separate vibrational bands were discovered in this region. The interaction scheme was deduced to be a three-way anharmonic resonance between the V₃, V₇ + VB, and 2v₆ levels with the fourth level, V₆ + V₁₂ induced by a Coriolis mechanism with the members of the triad. The first order anharmonic constants were approximated by a least squares fit of the triad intensities: W₃₇₈ = 8.4±0.1 cm⁻¹, W₃₆₆ = 15.8±0.4 cm⁻¹ with W₇₈₆₆ held fixed at zero. Perturbations from unseen interloper levels plus the fully correlated nature of the pure vibrational anharmonic interaction prevented a successful fit of the rotational structure of this system. Both the search/match and the intensity least squares algorithms were developed for this work. Four sub-bands in the red-orange region of the laser induced fluorescence spectrum of niobium nitride (NbN) were rotationally analyzed. Analysis of three sub-bands of the ³ϕ₂ - ³Δ₁ system allowed the vibrational spacings of each electronic state to be determined: ΔG½ = 986.351 cm⁻¹, ΔG1½ = 977.855 cm⁻¹ for the ³ϕ₂ state and ΔG1½, =. 1033.739cm⁻¹ for the ³Δ₁, state. The previously unassigned ³Π₁-³Δ₂ (0-0) sub-band was discovered 970 cm⁻¹ below its expected position of 18025 cm⁻¹. The electronic state assignment of this transition was confirmed by -wavelength resolved fluorescence measurements made with a diode array detector mounted on a spectrometer. A description of how the diode array detector was interfaced into the experiment is given. / Science, Faculty of / Chemistry, Department of / Graduate
15

The condensation of 3-nitro-4-halogenophenylarsonic acids with aliphatic amino compounds and phenols,

Maclay, William Dayton, January 1931 (has links)
Thesis (PH. D.)--University of Nebraska, 1931. / eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 24.
16

The condensation of 3-nitro-4-halogenophenylarsonic acids with aliphatic amino compounds and phenols,

Maclay, William Dayton, January 1931 (has links)
Thesis (PH. D.)--University of Nebraska, 1931. / eContent provider-neutral record in process. Description based on print version record. Bibliography: p. 24.
17

Metabolic diversity involved in biodegradation of 2-nitroimidazole and 5-nitroanthranilic acid

Qu, Yi 08 November 2010 (has links)
Evolution of strategies for biodegradation of synthetic organic pollutants relies on recruitment of genes from catabolic pathways for natural compounds. Investigation of metabolic diversity in nature can provide insight into biochemical strategies that could be recruited for bioremediation of pollutants. As part of a search for novel metabolic diversity we isolated soil bacteria able to degrade 2-nitroimidazole (2NI) and 5-nitroanthranilic acid (5NAA), and determined the biochemistry and molecular biology of their biodegradation pathways. 2NI and its analogs are increasingly used as prodrugs for the treatment of both tuberculosis and cancer. The biodegradation of 2NI by a soil Mycobacterium sp. is initiated by an unusual hydrolytic denitration. The reaction is catalyzed by a novel nitrohydrolase with a divergent sequence and represents the discovery of a previously unreported drug resistance mechanism in soil prior to its identification in clinical situations. 5NAA is the starting material for various nitroaromatic compounds and dyes. The biodegradation pathway of 5NAA is initiated by an unusual hydrolytic deamination. The corresponding gene is very distantly related to biochemically characterized genes in the NCBI database. The nitro group of 5NAA is eliminated as nitrite during the spontaneous formation of lactones from a ring fission product, a previously unreported mechanism. Degradation pathways of 5NAA and 2NI serve as precedents for those of nitroaniline and nitroimidazole pollutants. The work supports the hypothesis that the study of the metabolism of natural organic compounds selected on the basis of unusual structural features and ecological roles can reveal new metabolic diversity.
18

Purification and characterization of the hydroxylaminobenzoate lyase from pseudomonas pickettii YH105, cloned in escherichia coli

Hunter, Farley Allen. January 2008 (has links)
Thesis (M.S.)--Rutgers University, 2008. / "Graduate Program in Microbiology and Molecular Genetics." Includes bibliographical references (p. 33-34).
19

Sintese en karakterisering van nuwe amino(tio)karbeenkom[p]lekse van goud(I), goud(III) en koper(I)

Olivier, Pierre Jacobus 02 April 2014 (has links)
M.Sc. (Chemistry) / Please refer to full text to view abstract
20

Preparation of the first isothiazolinylidene complexes of Fe, W and Au

Desmet, Mieke Ann 21 July 2014 (has links)
M.Sc. / Please refer to full text to view abstract.

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