Synthesis and evaluation of conformationally constrained peptide replacements and studies toward the total synthesis of kidamycin

dc.contributor.advisorMartin, Stephen F.en
dc.creatorPlake, Hilary Ruthen
dc.date.accessioned2008-08-28T21:54:32Zen
dc.date.available2008-08-28T21:54:32Zen
dc.date.issued2004en
dc.descriptiontexten
dc.description.abstractA series of conformationally constrained pseudopeptides derivative of the tripeptide pYVN were designed and synthesized. The conformationally restricted compounds contained either trans- or cis-cyclopropanes as replacements to enforce locally extended and reverse turn peptide conformations, respectively. In addition, the proper flexible control molecules were prepared. All compounds were evaluated for the ability to bind to the Grb2-SH2 domain in order to determine the energetic consequences of introducing a conformational constraint into peptide ligands. No difference in the ∆Gbinding between the trans-cyclopropane and its control partner was observed. Surprisingly, there was an entropic disadvantage when comparing the binding energetics of the constrained and flexible pseudopeptides. Therefore, the introduction of the cyclopropane constraint was associated with an entropic disadvantage in the system, which is the opposite of conventional wisdom. An X-ray crystal structure of the trans- cyclopropane containing ligand bound to the Grb2-SH2 domain was obtained and vii discussed. On the other hand, cis-cyclopropane containing pseudopeptides do not seem to enforce the desired turn conformation of the ligand. A method to allow access to unsymmetrical C-aryl glycoside natural products was developed through employing a disposal tether to enforce the desired regioselectivity in a [4+2] cycloaddition between benzyne and glycosyl-substituted furan. Application of this novel strategy toward the synthesis of kidamycin is discussed. Additional synthetic routes, including utilizing Suzuki’s O → C glycoside rearrangement are also provided. Studies toward the synthesis of sugar ring E and F are illustrated.
dc.description.departmentChemistry and Biochemistryen
dc.description.departmentChemistryen
dc.format.mediumelectronicen
dc.identifierb59289600en
dc.identifier.oclc57686007en
dc.identifier.proqst3143448en
dc.identifier.urihttp://hdl.handle.net/2152/1292en
dc.language.isoengen
dc.rightsCopyright is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works.en
dc.subject.lcshPeptidesen
dc.subject.lcshPeptides--Synthesisen
dc.subject.lcshCyclopropaneen
dc.titleSynthesis and evaluation of conformationally constrained peptide replacements and studies toward the total synthesis of kidamycinen
dc.type.genreThesisen

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