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Studies of extended cyanines and related mixed valence compoundsZhao, Xiaodong 05 1900 (has links)
No description available.
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Design, synthesis and evaluation of novel inhibitors of cysteine proteases, metalloproteases and the proteasome, a unique high molecular weight proteolytic enzymeDotse, Anthony Kwabla 08 1900 (has links)
No description available.
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Preparation and characterization of thioaurite cluster compoundsSchaaff, T. Gregory 08 1900 (has links)
No description available.
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Monophosphines in asymmetric catalysisLaing, John Christopher Pettigrew January 1995 (has links)
This thesis described investigations into the synthesis and reactions of chiral monophosphines, in five chapters. Chapter 1 introduces asymmetric catalysis, Chapter 2 and 3 describe the synthesis of enantiomerically pure monophosphine via an oxide and borane route respectively. Chapter 4 describes the organometallic reactions of these monophosphines and Chapter 5 contains experimental details of the reactions. <strong>Chapter 1</strong> describes the importance of chirality and significant asymmetric processes. The literature methods of producing homochiral monophosphines are detailed. <strong>Chapter 2</strong> describes the synthesis of enantiomerically enriched monophosphine oxides. Diastereomerically pure (2R, 4S, 5R)-2-chloro-5-phenyl-3,4-dimethyl-1,3,2-oxazaphospholidine was prepared from PCl<sub>3</sub> and (-)-ephedrine. This compound was reacted with 2-adamantyl magnesium bromide to afford (2R, 4S, 5R) and (2S, 4S, 5R)-3,4-dimethyl-2-2-adamantyl-5-phenyl-1,3,2-oxazaphospholidin-2-oxide after oxidation with <sup>t</sup>BuOOH. An X-ray crystal structure was obtained of the R<sub>P</sub> diastereoisomer and a detailed NMR study carried out on the S<sub>P</sub> diastereoisomer. The R<sub>P</sub> diastereoisomer was reacted with 2-methoxyphenylmagnesium bromide to give R<sub>P</sub>-N-methyl-N-(1S,2S)-(1-methyl-2-hydroxy-2-phenyl)-ethyl-P-(2-methoxyphenyl)-P-(2-adamantyl)phosphinamide in 68% yield and 95% d.e. The ephedrinyl residue was replaced by O-methyl under acid catalysis with inversion of configuration and with >85% e.e. Displacement of the methoxy group using phenyl lithium occurred with inversion of configuration to give the corresponding phosphine oxide in 65% e.e., which could be reduced under forcing conditions using polymethylhydrosiloxane in the presence of Ti(O<sup>i</sup>Pr)<sub>4</sub>. <strong>Chapter 3</strong> describes the synthesis of enantiomerically enriched monophosphines via phosphine borane complexes. Diastereomerically pure (2R, 4S, 5R)-2,5-diphenyl-3,4-dimethyl-1,3,2-oxazaphospholidine borane was prepared directly from PhPCl<sub>2</sub> and (-)-ephedrine, followed by oxidation with BH<sub>3</sub>.Me<sub>2</sub>S. This compound reacted regiospecifically with ortho-anisyl lithium to afford the product formed by P-O cleavage with >96% d.e. and with retention of configuration at phosphorus. The ephedrinyl residue was replaced by O-methyl under acid conditions with inversion of configuration and with >98% e.e. Ferrocenyl, 1-adamantyl and tert-butyl lithium reagents displaced the methoxy group with inversion of configuration and with >92% e.e., as determined by <sup>1</sup>H NMR methods. The phosphine borane complexes were then reduced quantitatively with Et<sub>2</sub>NH with retention of configuration and with >98% e.e. <strong>Chapter 4</strong> describes the synthesis of indium and rhodium complexes of (S)-t-butyl-(2-methoxyphenyl)-phenyl phosphine and (S)-ferrocenyl-(2-methoxyphenyl)-phenyl phosphine. The iridium complexes are shown to reduce a range of prochiral olefins, including Z-methyl-2-acetylamino-3-phenylpropenoate (MAC) in up to 19% e.e. The di-(R,R)-(ferrocenyl-(2-methoxyphenyl)-phenyl phosphine) rhodium complex is more selective, reducing MAC in 54% e.e., while the rhodium complex of (S)-t-butyl-(2-methoxyphenyl)-phenyl phosphine reduces MAC in 24% e.e.
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Approaches to the asymmetric synthesis of non-steroidal anti-inflammatory drugs / by Robert Christian Griesbach.Griesbach, Robert Christian January 1996 (has links)
Bibliography: leaves 159-164. / iv, 158 leaves ; 30cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis examines routes for the asymmetric synthesis of three members of the nonsteroidal anti-inflammatory class of drugs (NSAIDs) The aryl propanoic acid ibuprofen is synthesized in 96% e.e. Control of stereochemistry is achieved by use of the Sharpless epoxidation reaction, followed by reduction of the product epoxide by complex hydride with assistance by titanium tetraisopropoxide acting as a Lewis acid. The final step is the coupling of an optically active carboxylic acid intermediate with the iso-butyl side chain to give (S)-ibuprofen. / Thesis (Ph.D.)--University of Adelaide, Dept. of Organic Chemistry, 1997?
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Asymmetric [alpha]-amino acid synthesis / by Pasquale Razzino.Razzino, Pasquale January 1991 (has links)
Bibliography : leaves 198-204. / vi, 204 leaves ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Organic Chemistry, 1992
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Asymmetric synthesis with vapol derivatives and novel chiral thiourea organocatalystsRampalakos, Konstantinos. January 2008 (has links)
Thesis (Ph.D.)--Michigan State University. Dept. of Chemistry, 2008. / Title from PDF t.p. (viewed on Mar. 27, 2009) Includes bibliographical references (p. 214-219). Also issued in print.
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Rational design, synthesis and study of novel [alpha]-hetero analogues of ACPA : towards sub-type selective ligands for glutamate-binding proteins /Nelson, Jared K. January 1900 (has links)
Thesis (Ph. D.)--University of Idaho, 2005. / Abstract. "August 23, 2005." Includes bibliographical references. Also available online in PDF format.
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Enones and enals as latent enolates in catalytic C-C bond forming processes total synthesis of (-)-paroxetine (Paxil®) /Koech, Phillip Kimaiyo, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
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Synthesis, resolution, and diastereoselectivity of the chiral auxiliary trans-2-(9H-flouren-9-yl)cyclohexanolCheney, Matthew A. January 2007 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2007. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
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