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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.
131

Reaction of some chelating thioesters with chlorotris (triphenylphosphine) rhodium (I) : a model of the initial stages of hydrodesulfurization

Uhm, Hae Won January 1986 (has links)
No description available.
132

Total synthesis of oxygenated lavendamycin analogs

Karki, Rajesh January 1998 (has links)
The synthesis of 7-acetyl-11'-benzyloxylavendamycin methyl ester (47), 7acetyl-11'-hydroxylavendamycin methyl ester (48), 11'-hydroxylavendamycin methyl ester (49), 11'-benzyloxylavendamycin methyl ester (50), are described. Pictet-Spengler condensation of 7-N-acetyl-2-formylquinoline-5,8-dione (26) with 5-benzyloxytrytophan methyl ester (45) or 5-hydroxytryptophan methyl ester (46) in dry xylene or anisole directly afforded lavendamycin analogs 47 or 48. Compound 49 was obtained by hydrolysis of 48 with 70% H2SO4 - H2Osolution. Compound 50 was obtained by hydrolysis of 47 with sodium carbonate solution.Aldehyde 26 was prepared according to the following general procedure. Nitration of 8-hydroxy-2-methylquinoline (28) yielded 8-hydroxy-2-methyl5,7-dinitroquinoline (29). Compound 29 was then hydrogenated and acylated with acetic anhydride to yield 5,7-bis(diacetamido)-8-hydroxy-2methylquinoline (31). Compound 31 was oxidized to give 5,8- dione 25 by using potassium dichromate. Treatment of compound 25 with selenium dioxide in refluxing 1,4-dioxane yielded compound 26.3 (Isopropylaminoethylidene)-6,7-dimethoxyindole (39) was prepared via the following procedure. Acylation of vanillin (32) with acetic anhydride yielded acetylvanillin (33). Compound 33 was nitrated and hydrolyzed to give 2nitrovanillin (35). Compound 35 was then methylated using dimethyl sulfate to produce 2-nitroveratric aldehyde (36). Condensation of compound 36 with nitromethane yielded 3,4-dimethoxy-2-f3-nitrostyrene (37). Ammonium formate reductive cyclization of compound 37 in refluxing methanol in the presence of a catalytic amount of 10% palladium on charcoal yielded 6,7dimethoxyindole (38). Electrophilic substitution reaction of compound 38 with ethylideneisopropylamine (41) in dry toluene yielded compound 39.Methyl (2RS, 3SR)-2-amino-3-[3-(5-benzyloxyindolyl)]butanoate (45) and methyl (2RS, 3SR)-2-amino-3-[3-(5-hydroxyindolyl)]butanoate (46) were obtained following the procedure described below. Electrophilic substitutionreaction of 5-bezyloxyindole (40) with ethylideneisopropylamine (41) in dry toluene yielded 3-(isopropylaminoethylidene)-5-benzyloxyindole (42). Condensation of compound 42 with methyl nitroacetate (43) in dry toluene gave methyl 3-[3-(5-benzyloxyindolyl)]3-nitrobutanoate (44). Hydrogenation of compound 44 in the presence of Raney nickel and trifluoroacetic acid in ethanol yielded methyl (2RS, 3SR)-2-amino-3-[3-(5-benzyloxyindolyl)] butanoate (45). Hydrogenation of compound 44 in the presence of 10% palladium on charcoal and trifluoroacetic acid in ethanol yielded methyl (2RS, 3SR)-2-amino-3-[3-(5-hydroxyindolyl)] butanoate (46).The structures of the novel compounds were confirmed by 1H NMR, IR, and HRMS or elemental analysis. / Department of Chemistry
133

Total synthesis of analogs of lavendamycin

Ebrahimian, G. Reza January 2003 (has links)
There is no abstract available for this thesis. / Department of Chemistry
134

Oligomeric tetrathiafulvalenes in supramolecular chemistry

Devonport, Wayne January 1995 (has links)
A range of highly ordered dendritic and oligomeric macromolecules, functionalised with tetrathiafulvalene (TTF) derivatives as a redox-active sub-unit were assembled. In particular, the first dendritic macromolecules incorporating TTF were constructed by the reaction of poly-acid chlorides and alcohol functionalities. Electrochemical techniques showed the novel redox-superstructures to be efficient π-electron donors that are able to undergo two reversible, multi-electron-on oxidations. The TTF-units were established to be acting independently, and the extent to which the redox groups could be oxidised was evaluated. UV studies demonstrated the redox- assemblies to be capable of forming charge-transfer complexes m solution and showed potential for the formation of conducting charge-transfer complexes. Preliminary studies showed the precursors to these compounds to be suitable for use as electrochemical detectors for dopamine. Structural variation of the core units increased the air and thermal stability of the dendritic materials, whilst retaining the characteristics of the multi-redox system. These systems formed stable aggregates of the radical cation and afforded conducting charge- transfer complexes with TCNQ. The new precursors to multi-TTF systems were then used in attempts to impart redox characteristics on [2]pseudorotaxanes and rotaxanes. Preliminary attempts were made to assemble multi-TTF systems using a TTF derivative as a core and at the periphery.
135

An investigation into the asymmetric synthesis of imidazolinones via reaction of chiral a-amino acid esters with nitriles /

Del Vecchio, Franklin A. January 1991 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1991. / Typescript. Includes bibliographical references (leaves 72-74).
136

Effects of organophosphate esters on blood vessels : a physiological, pharmacological, and histological assessment of involvement in organophosphorus-induced delayed neuropathy (OPIDN) /

McCain, Wilfred C., January 1900 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 167-187). Also available via the Internet.
137

I. Über campholsäure.

Jantsch, Otto, January 1917 (has links)
Inaug.-diss.--Basel. / Lebenslauf.
138

Synthesen hydroaromatischer Amidocarbonsäureester Habilitationsschrift ... /

Skita, Aladar. January 1906 (has links)
Thesis (Habilitationschrift)--Technische Hochschule "Fridericiana" zu Karlsruhe, 1906. / Includes bibliographical references (p. 104).
139

I. Über campholsäure.

Jantsch, Otto, January 1917 (has links)
Inaug.-diss.--Basel. / Lebenslauf.
140

Equilibria in hydrogenation of esters and indoles

Burks, Robert E. January 1947 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1947. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 78-79).

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