Synthesis of Dimeric Pyrrole-Imidazole Alkaloids
dc.contributor.advisor | Chen, Chuo | en |
dc.creator | Wang, Xiao | en |
dc.date.accessioned | 2013-01-17T16:18:31Z | |
dc.date.issued | 2013-01-17 | |
dc.description.abstract | Dimeric pyrrole-imidazole alkaloids, also known as oroidin family of alkaloids, are a class of marine natural products with unique structural diversity and complexity. Focusing on the synthesis of the higher order dimeric pyrrole-imidazole alkaloids, my graduate work comprises two components: a synthetic study of massadine and the total synthesis of ageliferin, as describe herein. These highly nitrogenated marine natural products possess a densely functionalized [3+2] or [4+2] dimerization core skeleton, which present significant synthetic challenges. A manganese(III)-mediated oxidative radical cyclization has been developed to construct the core skeleton of these pyrrole-imidazole dimers and its mechanism is investigated by the methods of computational chemistry. Ent-15-epi-5,11-dioxomassadine has been synthesized by using a biomimetic oxidative ring contraction converting ageliferin skeleton to massadine skeleton with stereochemical control, followed by an oxidative cyclization to construct the oxo-bridge. An asymmetric total synthesis of ageliferin is described, featuring an early installation of 2-azidoimidazole for the oxidative radical cyclization and a phosphorus imide group as a novel protecting group for 2-aminoimidazole. These synthetic studies support the possibility that a single-electron transfer (SET) reaction and a pinacol-type rearrangement may be used in nature as a way to produce ageliferin and massadine. | en |
dc.identifier.oclc | 841579494 | |
dc.identifier.uri | https://hdl.handle.net/2152.5/1261 | |
dc.subject | Imidazoles | en |
dc.subject | Pyrroles | en |
dc.title | Synthesis of Dimeric Pyrrole-Imidazole Alkaloids | en |
dc.type | Thesis | en |
dc.type.material | Text | en |
thesis.date.available | 2014-12-20 | |
thesis.degree.department | Graduate School of Biomedical Sciences | en |
thesis.degree.discipline | Biological Chemistry | en |
thesis.degree.grantor | UT Southwestern Medical Center | en |
thesis.degree.level | Doctoral | en |
thesis.degree.name | Doctor of Philosophy | en |
Files
Original bundle
1 - 1 of 1
Loading...
- Name:
- WangXiao.pdf
- Size:
- 31.19 MB
- Format:
- Adobe Portable Document Format
- Description:
- Dissertation Available after 12/20/2014