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dc.contributor.authorMunoz, Benitoen_US
dc.date.accessioned2009-10-02T13:19:54Z
dc.date.available2009-10-02T13:19:54Z
dc.date.issued1987-10-02T13:19:54Z
dc.identifier.urihttp://hdl.handle.net/10464/2742
dc.description.abstractToluene is converted to benzyl alcohol by the fungi Mortierella isabellina and Helminthosporium species; in the latter case, the product is further metabolized. Toluene-a -d 1 , toluene-a,a-d2, and toluene-a,a,a-d 3 have been used with Mortierellaisabellina in a series of experiments to determine both primary and secondary deuterium kinetic isotope effects for the enzymic benzylic hydroxylation reaction. The values obtained, intermolecular primary kH/kD = intramolecular p rim a r y kH r kD = 1. 0 2 + O. 0 5, and sec 0 n dar y k H I kD = 1. 37 .:!. 0.05, suggest a mechanism for the reaction involving benzylic proton removal from a radical intermediate in a non-symmetrical transition state. 2H NMR (30.7 MHz) studies using ethylbenzene-l,1-d 2 , 3 -fluoroethylbenzene-l,1-d 2 , 4 -fluoroethylbenzene-l,1-d 2 , and toluene-dB as substrates with Mortierella isabellina suggest, based on the observable differences in rates of conversion between the substrates, that the hydroxylation of hydrocarbons at the benzylic position proceeds via a one electron abstraction from the aromatic ring, giving a radical cation. A series of 1,3-oxathiolanes (eight) were incubated with Mortierella isabellina , Helminthosporium , Rhizopus arrhizus , and Aspergillus niger . Sulphoxides were obtained from Mortierella isabellina and Rhizopus arrhizus using the substrates 2-phenyl-, 2-methyl-2-phenyl-, and 2-phenyl-2-tert. butyl-l,3-oxathiolane. The relative stereochemistry of 2-methyl-2-phenyl-l,3-oxathiolan-l-oxide was assigned based on lH decoupling, n.O.e, 1 and H NMR experiments. The lH NMR (200 MHz) of the methylene protons of 2-methyl-2-phenyl-l,3-oxathiolan-l-oxide was used as a diagnostic standard in assigning the relative stereochemistry of 2-phenyl-l,3-oxathiolan-l-oxide and 2-phenyl-2-tert. butyl-l,3-oxathiolan-l-oxide. The sulphoxides obtained were consistent with an oxidation occurring from the opposite side of the molecule to the phenyl substituent.en_US
dc.language.isoengen_US
dc.publisherBrock Universityen_US
dc.subjectFungi.en_US
dc.subjectBiotransformation (Metabolism)en_US
dc.subjectHydrocarbons.en_US
dc.subjectSulfides.en_US
dc.titleBiotransformation of aromatic hydrocarbons and organic sulphides by fungien_US
dc.typeElectronic Thesis or Dissertationen_US
dc.degree.nameM.Sc. Chemistryen_US
dc.degree.levelMastersen_US
dc.contributor.departmentDepartment of Chemistryen_US
dc.degree.disciplineFaculty of Mathematics and Scienceen_US


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