The pyrrolizidine alkaloids : studies on the pyrrolizidine base Retronecanol

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dc.contributor.advisorCampbell, William Een_ZA
dc.contributor.authorWelgemoed, Jacobus Corneliusen_ZA
dc.date.accessioned2016-10-26T12:01:36Z
dc.date.available2016-10-26T12:01:36Z
dc.date.issued1968en_ZA
dc.description.abstractDegradative and biosynthetic studies were performed on retronecanol1 obtained from monocrotaline, the alkaloid present in Crotalaria spectabilis. Previously two different theories regarding the biosynthesis of the pyrrolizidine bases had been proposed. Conflicting results in this school emphasised the need for a critical examination of the degradative procedure. Heliotridane, derived from retronecanol, was submitted to the Hofmann degradation. The product of the reaction was shown by gas-liquid chromatography to be a mixture with at least five components. Attempts to separate and purify the components were unsuccessful, although some information regarding their identity was deduced. The mass spectra of retronecanol, heliotridane and heliotridene were obtained and plausible rationalisations of these spectra are presented. In order to circumvent the difficulties previously encountered in the degradation, attempts were made to obtain retronecanone from retronecanol by oxidation on a small scale. Three different oxidants, however, failed to give the required product. Plants of Crotalaria spectabilis were fed with [5-¹⁴C]-ornithine, followed by degradation of the active monocrotaline 1 obtained to give the activities of carbon atoms 1 and 1' of the pyrrolizidine base. The results are consistent with a theory which invokes a symmetrical intermediate in the biogenesis of ring B of the pyrrolizidine unit.en_ZA
dc.identifier.apacitationWelgemoed, J. C. (1968). <i>The pyrrolizidine alkaloids : studies on the pyrrolizidine base Retronecanol</i>. (Thesis). University of Cape Town ,Faculty of Science ,Department of Chemistry. Retrieved from http://hdl.handle.net/11427/22320en_ZA
dc.identifier.chicagocitationWelgemoed, Jacobus Cornelius. <i>"The pyrrolizidine alkaloids : studies on the pyrrolizidine base Retronecanol."</i> Thesis., University of Cape Town ,Faculty of Science ,Department of Chemistry, 1968. http://hdl.handle.net/11427/22320en_ZA
dc.identifier.citationWelgemoed, J. 1968. The pyrrolizidine alkaloids : studies on the pyrrolizidine base Retronecanol. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Welgemoed, Jacobus Cornelius AB - Degradative and biosynthetic studies were performed on retronecanol1 obtained from monocrotaline, the alkaloid present in Crotalaria spectabilis. Previously two different theories regarding the biosynthesis of the pyrrolizidine bases had been proposed. Conflicting results in this school emphasised the need for a critical examination of the degradative procedure. Heliotridane, derived from retronecanol, was submitted to the Hofmann degradation. The product of the reaction was shown by gas-liquid chromatography to be a mixture with at least five components. Attempts to separate and purify the components were unsuccessful, although some information regarding their identity was deduced. The mass spectra of retronecanol, heliotridane and heliotridene were obtained and plausible rationalisations of these spectra are presented. In order to circumvent the difficulties previously encountered in the degradation, attempts were made to obtain retronecanone from retronecanol by oxidation on a small scale. Three different oxidants, however, failed to give the required product. Plants of Crotalaria spectabilis were fed with [5-¹⁴C]-ornithine, followed by degradation of the active monocrotaline 1 obtained to give the activities of carbon atoms 1 and 1' of the pyrrolizidine base. The results are consistent with a theory which invokes a symmetrical intermediate in the biogenesis of ring B of the pyrrolizidine unit. DA - 1968 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 1968 T1 - The pyrrolizidine alkaloids : studies on the pyrrolizidine base Retronecanol TI - The pyrrolizidine alkaloids : studies on the pyrrolizidine base Retronecanol UR - http://hdl.handle.net/11427/22320 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/22320
dc.identifier.vancouvercitationWelgemoed JC. The pyrrolizidine alkaloids : studies on the pyrrolizidine base Retronecanol. [Thesis]. University of Cape Town ,Faculty of Science ,Department of Chemistry, 1968 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/22320en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentDepartment of Chemistryen_ZA
dc.publisher.facultyFaculty of Scienceen_ZA
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherChemistryen_ZA
dc.titleThe pyrrolizidine alkaloids : studies on the pyrrolizidine base Retronecanolen_ZA
dc.typeMaster Thesis
dc.type.qualificationlevelMasters
dc.type.qualificationnameMScen_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
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