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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

N-methylimidazole catalyzed acetylation for the analysis of hydoxy compounds

Pandit, Nivedita K. January 1978 (has links)
Thesis (M.S.)--Wisconsin. / Includes bibliographical references (leaves 60-63).
2

Phenylthio-controlled migrations around rings

Hannaby, M. P. January 1985 (has links)
No description available.
3

Regioselective Reduction of N-Alkyl-3-sulfonyl Glutarimides. Synthesis of 3,4-Dihydro-5-tosylpyridin-2-ones

Hsu, Ru-Ting 30 July 2001 (has links)
In this report, we described a general method which could regioselectively reduce the carbonyl group on 3-sulfonyl glutarimides and lead to the corresponding hydroxy piperidones (hydroxy lactams) and further converted to 3,4-dihydro-5-tosylpyridin-2-ones .
4

Synthesis of oxygenated mycolic acids

Theunissen, Cornelia Elizabeth January 2012 (has links)
No description available.
5

Influence de la taille du cycle sur le cours de la transposition pinacolique d'hydroxy-1 cycloalcoyl carbinols... /

Crouzet, Jean, January 1900 (has links)
Texte remanié de: thèse--Sc. phys.--Montpellier, 1968. / Extrait du "Bulletin de la Société chimique de France" 1968, n° 12, pp. 4842-4850. Conservé sous la cote: [4° V. 25887 (17)].
6

Study of the mechanism of oxidative decarboxylation of [alpha]-hydroxy acids by bromine water

Pink, Judith Margaret Osyany January 1969 (has links)
A kinetic study of the mechanism of oxidative decarboxylation of α-hydroxy acids by bromine water throughout the pH range revealed two distinct reactions paths. At low pH HOBr rather than Br₂ is the oxidant. The reaction kinetics is complex in bromine water but a second order rate law is observed when the formation of bromide is suppressed by the addition of silver ion,, On the basis of the pH - rate profiles, solvent isotope effect and the insensitivity of reaction rate to α-deuteration it is concluded that HOBr attacks the undissociated hydroxy acid but the rate controlling step also involves a base catalyzed proton loss from the hydroxyl group. Calculated pH - rate profiles, based on a steady state treatment, are in agreement with the observed values for all three model compounds studied in detail: benzilic, mandelic and 2-hydroxy-2-methylpropanoic acids. Rate equations are also derived for the complex reactions occurring in the presence of accumulating bromide. The mechanism of α-hydroxy acid oxidation is compared with the oxidation pattern of alcohols and of oxalic acid in the bromine water system. Above pH 6 molecular bromine is found to be the most important oxidant for α-hydroxy acid. Slow oxidation also occurs by HOBr but not by OBr¯. The reaction is general base catalyzed. A rate expression is derived, based on a steady state treatment, assuming carboxylate - Br₂ and carboxylate - HOBr reactions with concurrent base catalyzed loss of the hydroxylic proton. The calculated rate constants are in good agreement with the values observed both in the presence and absence of added bromide. Results are also presented of: 1) A preliminary investigation of oxidative decarboxylation of α-amino acids by bromine water. 2) A study of the oxidation of α-hydroxy and α-amino acids by permanganate throughout the pH range. / Science, Faculty of / Chemistry, Department of / Graduate
7

Novel Organophosphorus Oligomers. Synthesis and conformation of ¿-hydroxy phenylphosphinates.

Royappa, Martin January 2010 (has links)
Chapter one reviews the recent progress in the synthesis of phosphonopeptides, pseudopeptides containing a phosphinic, phosphonic or phosphonamide linkage in place of an amide (peptide) linkage. It describes some of the general methods for the synthesis of these pseudopeptides; for example through couplings to the nitrogen of an ¿-aminophosphonic acid, or Michael addition to acrylates, as well as other methods, the scope for which are not as wide yet. It also provides a summary of the reported biological activities of this class of pseudopeptides. Chapter two contains the results and discussion for a novel method for the synthesis of ¿-hydroxy phenylphosphinate oligomers as well as hybrid oligomers containing ¿-hydroxy phenylphosphinic acid and ¿-amino carboxylic acids. In particular, synthesis of a series of dimeric ¿-hydroxy phenylphosphinates are reported. The analysis of these dimers by a combination of NMR spectroscopy, X-ray crystallography and computational methods shows intramolecular hydrogen bonding in these molecules depends on the relative configuration of the carbon and phosphorus atoms. However, although the development of the synthetic methods was successful, the separation and isolation of the diastereomers was not always possible, which hindered a more comprehensive analysis of folding patterns in these molecules. Chapter three contains the experimental procedures, preparation and spectroscopic characterisation of all the chemical compounds. Crystal data and details of crystal structures are in the Appendix. / EPSRC
8

Utilisation de la réaction de Henry dans la synthèse d'isostère hydroxy-éthylène

Brassard, Martin January 2004 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
9

Novel organophosphorus oligomers : synthesis and conformation of α-hydroxy phenylphosphinates

Royappa, Martin January 2010 (has links)
Chapter one reviews the recent progress in the synthesis of phosphonopeptides, pseudopeptides containing a phosphinic, phosphonic or phosphonamide linkage in place of an amide (peptide) linkage. It describes some of the general methods for the synthesis of these pseudopeptides; for example through couplings to the nitrogen of an α-aminophosphonic acid, or Michael addition to acrylates, as well as other methods, the scope for which are not as wide yet. It also provides a summary of the reported biological activities of this class of pseudopeptides. Chapter two contains the results and discussion for a novel method for the synthesis of α-hydroxy phenylphosphinate oligomers as well as hybrid oligomers containing α-hydroxy phenylphosphinic acid and α-amino carboxylic acids. In particular, synthesis of a series of dimeric α-hydroxy phenylphosphinates are reported. The analysis of these dimers by a combination of NMR spectroscopy, X-ray crystallography and computational methods shows intramolecular hydrogen bonding in these molecules depends on the relative configuration of the carbon and phosphorus atoms. However, although the development of the synthetic methods was successful, the separation and isolation of the diastereomers was not always possible, which hindered a more comprehensive analysis of folding patterns in these molecules. Chapter three contains the experimental procedures, preparation and spectroscopic characterisation of all the chemical compounds. Crystal data and details of crystal structures are in the Appendix.
10

N-hydroxy-2-acetylaminofluorene sulfotransferase its significance in the macromolecular binding and carcinogenicity of the amino-fluorenes in rat liver.

De Baun, Jack Rollie, January 1969 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. Includes bibliographical references.

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