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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.
91

Pricing of multi-name credit derivatives using copulas

Liu, Xinjia. January 2008 (has links)
Professional Master's Project in partial fulfillment of the requirements for the degree of Master of Science (M.S.)--Worcester Polytechnic Institute. / Keywords: first-to-default baskets; multi-name credit derivatives; copula functions. Includes bibliographical references (leaf 29 ).
92

Solvolytic and mass spectral studies of some [omega]-cyclooctatetraenylalkyl derivatives.

Mular, Michael. January 1974 (has links) (PDF)
Thesis (Ph.D. 1974) from the Dept. pf Organic Chemistry, University of Adelaide.
93

The QR algorithm for eigenvalue estimation theory and experiments /

Feng, Wei, Pate, Thomas H., January 2008 (has links)
Thesis--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 48).
94

Singular perturbation methods in credit derivative modeling

Koo, Jawon, January 2010 (has links)
Thesis (Ph. D.)--Rutgers University, 2010. / "Graduate Program in Mathematics." Includes bibliographical references (p. 78-79).
95

Prices of credit default swaps and the term structure of credit risk

Desrosiers, Mary Elizabeth. January 2007 (has links)
Thesis (M.S.) -- Worcester Polytechnic Institute. / Keywords: Credit risk; Credit default swaps. Includes bibliographical references (leaf 32).
96

Improving Financial Statement Footnotes: Evidence from Derivative and Hedging Disclosures

Steffen, Thomas January 2015 (has links)
<p>I investigate whether changes in derivative and hedging footnote disclosures required by SFAS 161 affect investor and analyst uncertainty. My study is motivated by accounting standard setters' and researchers' interest in disclosure effectiveness, and by prior research linking investors' interpretations of public information to measures of uncertainty. For a broad sample of firms, I use textual analysis to measure changes in the amount and salience of derivative and hedging information caused by SFAS 161. Using a difference-in-differences design to study the effects of these changes, I find that investor uncertainty is reduced for firms adopting SFAS 161. In addition, I find that for some uncertainty proxies this reduction is greater for firms whose disclosures were more affected by SFAS 161, consistent with the new disclosures improving investor understanding. I also find evidence of a decreased association between bid-ask spread and movements in risk factors, indicating that SFAS 161 reduced uncertainty stemming from these movements.</p> / Dissertation
97

The atomistic simulation of potential angiogenic inhibitors

Allen, Andrew David January 1996 (has links)
This thesis concerns the atomistic investigation of the extra-cellular protein angiogenin. The main aims of this project are to propose new potential inhibitors to the angiogenin, and to investigate how they might bind to the protein. Two main families of inhibitors have been investigated; firstly, anthracycline antineoplastic antibiotics of which adriamycin is the parent drug; and secondly, uridine and cytidine nucleotide derivatives. The project has been divided into four research areas; conformational analysis of adriamycin; conformational analysis of nucleotide derivatives; a comparative study of the published crystal structure of angiogenin and a published in-house homology model of the protein; finally a series of docking studies to explore the similarity of the active site of angiogenin to ribonuclease A. Angiogenin has been shown to be 68% similar to ribonuclease A on an atom-by-atom basis, and a new sequence alignment has been produced following the release of the crystal structure of angiogenin.
98

Baylis-Hillman derived benzopyrans and related systems : a synthetic and mechanistic study

Robinson, Ross Stuart January 1998 (has links)
The Baylis-Hillman reaction between substituted salicylaldehydes and various acrylate species has been shown to afford complex reaction mixtures, careful chromatography of which has led to the isolation of an extensive range of novel compounds. One- and two-dimensional NMR spectroscopic, mass spectrometric and X-ray crystallographic analysis of these compounds have permitted identification of no less than eight general classes of chromene and coumarin derivatives. The formation of the various product types is attributed to cascades of successive reactions stemming, in each case, from a Baylis-Hillman product as the common intermediate. The mechanistic sequence involved in the formation of the various chromene and coumarin derivatives have been elucidated by examining isolated or specifically prepared compounds as putative reaction intermediates. Conjugate addition and acyl or allylic substitution by various nucleophiles appear to be common processes in the formation of the chromene and coumarin derivatives, and studies focussing on these processes have been undertaken. Reactions of Baylis-Hillman adducts have been carried out, using oxygen, sulfur and nitrogen nucleophiles, in order to explore stereoselectivity and regioselectivity trends. The results show that the reactions proceed with a very high degree of regioselectivity, affording conjugate addition rather than acyl substitution products. The diastereoselectivity observed for the addition products, however was typically low. A kinetic study to explore the regioselectivity of the reaction between various Baylis-Hillman derived halogeno esters and the nucleophile, methyl 3-oxobutanolate enloate, in two different base-solvent systems at high dilution was also undertaken. The reactions were monitored by ¹H NMR spectroscopy, and the results revealed that the reaction kinetics are more complex than originally anticipated. A mechanistic rationalisation is offered which is consistent with both the kinetic data and the observed regioselectivity trends.
99

Application of Baylis-Hillman methodology in the construction of complex heterocyclic targets

Ganto, Mlungiseleli MacDonald January 2009 (has links)
Baylis-Hillman reactions using various aromatic aldehydes, activated alkenes and catalysts have been used to: - access an extensive range of poly-heterocyclic products;explore chemoselectivity; and optimise reaction efficiency. Chromone-3-carbaldehydes and chromone-2-carbaldehydes, prepared via Vielsmeier-Haack and Kostanecki-Robinson methodology, respectively, have been used as Baylis-Hillman substrates with four different catalysts, viz., 1,4-diazabicyclo[2.2.2]octane (DABCO), 3-hydroxyquinuclidine (3-HQ), imidazole and N’,N’,N’,N’- tetramethylpropanediamine (TMPDA), and with methyl vinyl ketone (MVK), methyl acrylate, cyclic enones (2-cyclohexen-1-one, 2-cyclopenten-1-one and chromones) as activated alkenes. Reactions of the chromone- -carbaldehydes with MVK afforded dimeric Baylis-Hillman adducts when catalyzed by DABCO but when the same reactions were repeated using 3-HQ as catalyst, the dimeric products were accompanied by tricyclic Baylis-Hillman adducts. Use of excess MVK, however, led to mixtures of the normal Baylis-Hillman adducts and the tricyclic adducts – interestingly, with the apparent absence of the dimeric products. While reactions of chromone-3-carbaldehydes with methyl acrylate afforded the normal Baylis-Hillman adducts, the chromone-2- carbaldehydes produced, instead, rearrangement products, consistent with an earlier, single observation. Reactions of 2-nitrobenzaldehydes with cyclic enones using imidazole as catalyst afforded the normal Baylis-Hillman adducts, reductive cyclisation of the 2-cyclohexen-1- one and 2-cyclopenten-1-one adducts, using acetic acid and iron powder, afforded the corresponding quinoline erivatives. Treatment of cyclic enones with pyridine-2-carbaldehydes and quinoline-2-carbaldehydes using TMPDA as catalyst generally gave the expected Baylis-Hillman adducts. However, indolizine derivatives were isolated directly from Baylis-Hillman reactions involving pyridine-2-carbaldehydes and 2-cyclohexen-1-one. The remaining Baylis-Hillman adducts were cyclized to the corresponding indolizines by treatment with acetic anhydride both under reflux and under microwave-assisted conditions, the latter approach providing remarkably rapid and efficient access to the polycyclic products. Computer modelling studies have been conducted on selected polycyclic products at the Molecular Mechanics (MM), Quantum Mechanical (QM) and Density Functional (DFT) levels. The theoretical results have been used to calculate UV, IR and NMR absorption data, which have been compared, in turn, with the experimental spectroscopic data. Use has also been made of the estreNova NMR prediction programme and, generally, good agreement has been observed between the predicted and experimental spectroscopic data.
100

Chemical studies of chromone derivatives

Sabbagh, Liezel Veronica January 2001 (has links)
This study has focussed on several aspects of chromone chemistry, viz., (i) the influence of remote substituents on the basicity of 2-(N,N-dimethylamino)chromones, (ii) MoritaBaylis-Hillman reactions of substituted chromone-3-carbaldehydes and (iii) an investigation into the application of chromone chemistry in the total synthesis of the marine natural product, Rietone A. Selected 2-(N,N-dimethylamino )chromones were prepared using two different methods; firstly, via cyclisation of salicylate-derived N,N-dimethyl-3;.(2-hydroxyphenyl)-3- oxopropanamide precursors and, secondly, via 2-hydroxyacetophenone boron difluoride complexes. ¹³C NMR analysis of the 6- and 7-methoxy-2-(N,N-dimethylamino)chromones confirmed that protonation occurs at the chromone carbonyl oxygen rather than the amino nitrogen - a conclusion supported by mol~cular orbital calculations. Potentiometric analysis of 2-(N,N-dimethylamino )chromones in ethanol-water afforded pKa (pK [subscript a]) values in the range 2.22 - 2.52. The observed trend has been rationalised in terms of substituent effects with the aid of molecular orbital calculations at the semi-empirical and ab initio levels, while hydrogen-bonding effects have been used to account for the apparently anomalous result obtained for the 6-nitro derivative. A series of seven substituted chromone-3-carbaldehydes, prepared by the application of Vilsmeier-Haack methodology to the corresponding 2-hydroxyacetophenones, have been examined as substrates for Morita-Baylis-Hillman reactions, using DABCO as the catalyst and three different activated alkenes, viz., methyl acrylate, methyl vinyl ketone and acrylonitrile. In all cases, with the exception of 6-nitrochromone-3-carbaldehyde, the reactions have been shown to afford the expected Morita-Baylis-Hillman products. Use of methyl acrylate and methyl vinyl ketone as the activated alkene has been observed to afford additional, unprecedented dimeric products, which have been unambiguously characterised using a combination of single crystal X-ray analysis and spectroscopic (high resolution MS and NMR) techniques. Different dimer-like adducts have been isolated from reactions in which acrylonitrile was used as the activated alkene, and the structures of these novel products have-been determined <spectroscopically. Tentative mechanistic rationalisations for the formation of the "dimeric" products have been presented. Optimisation studies, aimed at improving the yields of the Morita-Baylis-Hillman products, have resulted in significant increases in conversion efficiency (up to 95%). It has also been shown that the Morita-Baylis-Hillman products may be readily converted to the corresponding "dimers". An exploratory study into the synthesis of Rietone A has been initiated. Ring-opening of a chromone derivative was expected to provide access to the aromatic moiety, while retrosynthetic analysis of the aliphatic side chain suggested possible strategies for its construction. These approaches have proved largely unsuccessful, but preliminary studies involving Fries rearrangement of 4-(carbomethoxymethyl)phenyl 3,7-dimethyl-2,6-octadienoate appear to hold some promise for future development.

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