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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

Formation of heterocyclic n-nitrosamines from the reaction of nitrite and selected primary diamines and amino acids

Warthesen, Joseph John 25 June 1974 (has links)
The reaction of several primary amines with nitrite was investigated with regard to the formation of N-nitrosamines. When reacted in a low moisture system at 160°C with a 1:2 molar ratio of amine to sodium nitrite, various primary amine hydrochloride salts were found to give rise to heterocyclic nitrosamines. The amines and yields of nitrosamines were as follows: putrescine, 22% nitrosopyrrolidine; cadaverine, 21.5% nitrosopiperidine; ornithine, 1% nitrosopyrrolidine and 3% nitrosoproline; lysine, 1% nitrosopiperidine and 2.5% nitrosopipecolic acid. Nitrosamine analysis was by gas chromatography and identification was confirmed by mass spectrometry. The analysis of the nitrosamino acids was facilitated by making the methyl ester derivatives. When the reactions were carried out in buffered solution at temperatures up to 100°C, the same products were identified except ornithine did not produce nitrosopyrrolidine and lysine did not produce nitrosopiperidine. The pH optimum for the formation of nitrosopyrrolidine was 3.8 and the pH optimuna for the production of nitrosopipecolic acid from lysine was 3.4. Substantial differences in nitrosamine yield were noted when various types of buffer were used. The effects of time and temperature were investigated with nitrosamines being produced at temperatures as low as 22°C. The concentration of nitrite influenced nitrosamine yield dramatically and the reaction rate appeared to be second order with respect to nitrite concentration. Theoretical yields of heterocyclic nitrosamines from primary diamines reacted with nitrite in buffer were as high as nine percent. On a comparative basis, yields of five-membered heterocyclic nitrosamines were higher than the six-membered ring compounds, and the amino acids gave higher yields of the respective nitrosamines than did the simple diamines. When butylamine was reacted with nitrite, dibutylnitrosamine was identified as a product. Yields were extremely low in solution, but as a high temperature-low moisture reaction, one percent of the nitrosamine was formed. A system similar to frying bacon was used to determine if putrescine could contribute to the formation of nitrosopyrrolidine in cooked bacon. Ground pork belly containing 200 ppm sodium nitrite was cooked to 177°C and the cooked meat, cooked-out fat, and cooking distillate were combined and analyzed for nitrosopyrrolidine. An average of 109 ppb nitrosopyrrolidine was detected without added putrescine. When 0.40% putrescine was added to the pork prior to cooking, an average of 321 ppb nitrosopyrrolidine was formed. In another set of cooking experiments, only the distillate was analyzed. Increased amounts of nitrosopyrrolidine were detected when the pork contained added putrescine or proline. / Graduation date: 1975
2

The physiological and pharmacological actions and fate of several sympathomimetic amines in vascular beds

Jellett, Leon Barry January 1971 (has links)
165 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (M.D.) from the Dept. of Human Physiology and Pharmacology, University of Adelaide, 1972
3

A study of the reaction of some aromatic amines with glyoxal

Collier, Robert Wade 08 1900 (has links)
No description available.
4

The physiological and pharmacological actions and fate of several sympathomimetic amines in vascular beds.

Jellett, Leon Barry. January 1971 (has links) (PDF)
Thesis (M.D.) from the Dept. of Human Physiology and Pharmacology, University of Adelaide, 1972.
5

Substances formed by the interaction of some aliphatic primary monamines and of ethylene-diamine with the salts of certain metals ...

Moore, Charles James, January 1901 (has links)
Thesis (Ph. D.)--University of Virginia, 1901.
6

Studies on proteinogenous amines [II] A microchemical colorimetric method for estimating imidazole derivatives. [III] A quantitative method for separating histamine from histidine. [IV] The production of histamine from histidine by Bacillus coli communis ... /

Koessler, Karl Konrad, Koessler, Karl Konrad, Koessler, Karl Konrad, Koessler, Karl Konrad, Hanke, Milton Theodore, January 1900 (has links)
Thesis (Ph. D.)--University of Chicago, 1919. / By Karl K. Koessler and Milton T. Hanke. "Private edition, distributed by the University of Chicago Libraries, Chicago, Illinois." "Reprinted from the Journal of biological chemistry, Vol. XXXIX, No. 3, October 1919." "The first article of this series was published in J. Am. chem. soc., 1918, XL, 1716." Includes bibliographical references.
7

The Molecular rearrangement of triphenylmethylhalogenamines ...

Vosburgh, Isabelle Marion, January 1900 (has links)
Thesis (Ph. D.)--University of Chicago. / Vita. "A Private Edition Distributed by the University of Chicago Libraries." "Reprinted from the Journal of the American Chemical Society, Vol. 38, No. 10, 1916." Includes bibliographical references.
8

The Molecular rearrangement of triphenylmethylhalogenamines ...

Vosburgh, Isabelle Marion, January 1900 (has links)
Thesis (Ph. D.)--University of Chicago. / Vita. "A Private Edition Distributed by the University of Chicago Libraries." "Reprinted from the Journal of the American Chemical Society, Vol. 38, No. 10, 1916." Includes bibliographical references.
9

Inhibition of the inotropic responses to certain sympathomimetic amines by tetramethylammonium and d-tubocurarine

Lamela, Mariano. January 1961 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1961. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 67-72).
10

Studies on proteinogenous amines : [II] A microchemical colorimetric method for estimating imidazole derivatives. [III] A quantitative method for separating histamine from histidine. [IV] The production of histamine from histidine by Bacillus coli communis ... /

Koessler, Karl Konrad, Koessler, Karl Konrad, Koessler, Karl Konrad, Koessler, Karl Konrad, Hanke, Milton Theodore, January 1900 (has links)
Thesis (Ph. D.)--University of Chicago, 1919. / By Karl K. Koessler and Milton T. Hanke. "Private edition, distributed by the University of Chicago Libraries, Chicago, Illinois." "Reprinted from the Journal of biological chemistry, Vol. XXXIX, No. 3, October 1919." "The first article of this series was published in J. Am. chem. soc., 1918, XL, 1716." Includes bibliographical references.

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