Global ETD Search
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Showing 1 to 11 of 11 for “"asymmetric dihydroxylation"”.
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Asymmetric Dihydroxylation and Aziridination of Allenes and Related Chemistry
A novel method for asymmetric synthesis of α-hydroxy ketone with excellent regio- and stereoselectivity has been established by the systematic investigation of asymmetric dihydroxylation of allenes. The efficiency of kinetic resolution of racemic allenes was also investigated by using the AD …
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Synthetic and mechanistic studies of the osmium-catalyzed asymmetric dihydroxylation of olefins
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, 1993
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Synthesis of cinchona alkaloid analogues as mechanistic probes of the osmium-catalyzed asymmetric dihydroxylation of olefins
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1991.
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The Synthetic Utility of Enol Derivatives and the Directed Aryltitanation of Homoallylic and Allylic Alcohols
… enol benzoates are subjected to the Sharpless Asymmetric Dihydroxylation to form enantiomerically enriched alpha-hydroxy aldehydes. Due to their instability, these alpha-hydroxy aldehydes are further transformed in situ to demonstrate their utility in organic synthesis. The second and third …
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Asymmetric synthesis of novel anthracyclinones
… prepared by an ene cyclisation and subjected to asymmetric dihydroxylation (AD). The products from the AD reactions are of considerable biological interest and have been characterized. Their stereochemistry has been assigned by 1H nmr comparisons with the parent diphenols, which have resulted in …
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The application of organocatalytic Asymmetric Epoxidation
… of target natural product synthesis, catalytic asymmetric synthesis has become a vital tool to obtain enantiomerically pure compounds, and is often used in the synthesis of natural products as a key step.1 For example, the asymmetric dihydroxylation was used in synthesis of gibberellic acid …
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Generating structural diversity in \(\alpha\)[alpha],\(\alpha\)[alpha]-difluoromethyl ketones
… have been tested for reactivity in Sharpless Asymmetric Dihydroxylation. A 1,4-diene has been converted through to a fluorinated analogue of a dideoxyxylulose. A 1,3-diene has been successfully converted through to a difluorodeoxyxylulose of current interest. Key points involve regioselective …
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Asymmetric synthesis involving silicon
… silylated diols (17 pairs) have been prepared by asymmetric dihydroxylation of the corresponding allyl and vinylsilanes using Sharpless catalysts. Chiral analysis of these silyl diols was carried out by <sup>1</sup>H NMR methods in the presence of Eu(hfc)<sub>3</sub>. Enantiomeric purity of some …
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Total synthesis of a virotoxin and analogs for conformational studies
… residue, including a diastereoselective dihydroxylation. Nα-Carbobenzyloxy-(2S)-4,5-dehydroleucine was coupled with valine ethyl ester to give a dipeptide that was subjected to a Sharpless asymmetric dihydroxylation to introduce the diol. The relative configuration at C4 was assigned as S …
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SYNTHESIS AND EVALUATION OF FOSMIDOMYCIN ANALOGUES AS ANTIMALARIAL AGENTS
… were explored. A 10-step sequence, involving an asymmetric dihydroxylation, afforded compound 5.1 in a reasonable yield. Unfortunately, this compound did not show any worth mentioning inhibitory activity. In conclusion, this Ph.D. thesis highlights some important structural requirements for DXR …
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PREPARATION AND EVALUATION OF DECONSTRUCTION ANALOGS OF 7-DEOXYKALAFUNGIN AS AKT INHIBITORS
Pyranonaphthoquinone lactones have been recently found to be selective inhibitors of the serine-threonine kinase AKT/PKB. AKT/PKB plays a major role in tumorigenesis, hence these compounds have a great potential to act as anti-cancer agents. They act by a novel bioreductive alkylation mechanism of …