Record Details
Chemical methods for combinatorial library synthesis and stereoselective glycosidation
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Chemical methods for combinatorial library synthesis and stereoselective glycosidation |
| Names |
Bowers, Albert A.
(creator) |
| Date Issued | 2007 (iso8601) |
| Note | Access restricted to the OSU Community |
| Abstract | This thesis describes the development of four synthetic methodologies: a one-pot reaction for glycopeptides synthesis, two different routes to stereoselective glycosylation, and a method for preparation of small molecule libraries via a persistent radical effect. In the first part of chapter one, the difficulty and importance of glycopeptides synthesis is explained. A brief survey of available methods is given. In the second portion, the challenge of the 1,2-cis-equatorial glycosidic linkage is described, with specific attention to the [beta]-D-rhamnosides and their natural occurrence. The third section presents methods of sequential glycosylation and the benefits of true iterative strategies for oligosaccharide synthesis. The last part of the first chapter provides a brief overview of methods for employing equilibrium reactions in rapid affinity screening. In chapter two, the ring-opening of thioanhydrides and subsequent trapping with electron-deficient sulfonamides and azides is employed in a one-pot route to diamides. The chemistry is extended to amino acid based thioanhydrides and synthesis of a glycopeptides. The third chapter describes the development of a second generation radical fragmentation route to [beta]-D-rhamnosides. The fragmentation is further investigated in synthesis of a repeat [beta]-(1-->3)-linked tetrarhamnan from the lippopolysacchraide O-chain of E. Hermanii. In the fourth chapter, results from efforts to prepare glycosyl "cation pools" are presented. The essentially reagent free glycosylation is demonstrated as viable method for iterative glycosylation. The fifth chapter briefly explains the persistent radical effect and its application in synthesis of small libraries of alkoxylamines. Results of library deconvolution via fluorous chromatography are also given. Chapter six derives some conclusions from the work presented and chapter seven gives experimental details and characterization. |
| Genre | Thesis |
| Topic | Glycosides -- Synthesis |
| Identifier | http://hdl.handle.net/1957/53429 |
