Dissertations / Theses: 'Methodology of synthesis'

1

Coghlan, Samuel William. "Phosphoinositides : methodology, synthesis, application." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612939.

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2

Wang, Shouming. "Synthetic methodology and synthesis using #alpha#,#beta#-epoxyaldehydes." Thesis, University of Salford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328053.

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3

Foot, Jonathan Stuart. "New synthetic methodology and antiviral natural product synthesis." Thesis, University of York, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412621.

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4

Tang, Andrew. "Synthetic methodology towards the synthesis of sesquiterpene lactones." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612321.

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5

Drouin, Ludovic. "New methodology for oligosaccharide synthesis." Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444903.

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6

Bland, Lorraine. "Methodology for chemical protein synthesis." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/12014.

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A number of groups have been investigated as potential protecting groups for the thiol functionality of cysteine residues during Solid Phase Peptide Synthesis. Of these the 4-picolyl system has been found to be successful. A short, efficient synthesis to the protected amino acid and mild cleavage conditions have been developed. This protected amino acid has been applied in the synthesis of a number of interesting cysteine-containing peptide targets. Deglycosylated human erythropoietin (dhEPO) has been synthesised by SPPS, employing the picolyl group for cysteine protection. Purification of this material has been achieved by gel filtration. The synthetic material has been characterised by amino acid analysis, SDS-PAGE, iso-electric focusing and N-terminal sequencing. Attempts have been made to synthesise deglycosylated human erythropoietin via a fragment coupling technique. All fragments were successfully synthesised and purified and model ligation studies carried out.

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Hyland, Christopher James Timothy. "Stereoselective Î³-lactam synthesis : methodology and natural products synthesis." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410055.

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8

Simon, Binto. "The development of synthetic methodology for stereoselective synthesis of aminoglycosides." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/the-development-of-synthetic-methodology-for-stereoselective-synthesis-of-aminoglycosides(746860dc-9b11-41b9-8283-9201d5149cd9).html.

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RNA is recognised as an important biomolecule involved in many broad cellular functions such as transcription, translation regulation and protein synthesis. Most pathogenic viruses replicate their genome as RNA during some stages in their life cycle. There is an urgent need to develop new methods to treat numerous viral diseases by targeting RNA and to understand the processes by which RNA-protein complexation can be inhibited. Our study focuses on the interactions between the HIV-1 Rev Responsive Element RNA (RRE) with a series of aminoglycosides developed jointly between our group in Manchester and GSK (USA). Even though a number of novel aminoglycoside have been explored previously, they are complex, large molecular weight compounds with low specificity, which limits their use as RNA recognition ligands and anti-viral drugs. The key problem is to be able to synthesise precursors by short, direct routes, avoiding significant detours caused by traditional carbohydrate protecting group strategies, while still delivering sterocontrol and opportunities to diversify. In chapter II we describe our efforts to synthesize the 6-glucosamine moiety (A-ring). A flexible synthesis of 6-aminoglucosamine derivatives can be accomplished in 5 steps using a totally regioselective enzymatic hydrolysis, controlled oxidation to sensitive but manageable aldehydes (hitherto rarely accomplished with a C-4 OAc), and reductive amination technology that allow for unprecedented diversification. In a different approach stereocontrolled synthesis of a model compound was achieved in 4 steps including a novel TEMPO oxidation and a one-pot oxidation/imine-reduction for the complete synthesis of the molecule.Chapter III describes our attempts towards the development of a robust stereoselective O-glycosylation strategy using Lewis acids. In pursuance of an efficient synthesis of our designed RNA binder target compound the stereoselective formation of the glycosidic linkage connecting the A-ring with the 2-DOS ring is an important step. This chapter also gives a general overview of the challenges involved in glycosylation followed by the strategies we employed to overcome some of these issues. We discuss our unusual stereocontrolled glycosylation in which, despite a neighbouring “participatory” group at C-2, the α-glycoside is delivered in high yield. This result implies that the reaction does not occur through a conventional neighbouring group participation.

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Karim, Rehana. "Development of radical synthetic methodology using solid-phase organic synthesis." Thesis, Loughborough University, 2003. https://dspace.lboro.ac.uk/2134/34406.

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The synthesis of heterocycles using radical intermediates has become an important area of research in recent years. The aim of our research was to develop radical methodologies to construct heterocycles on solid-support. Tri-cyclic benzimidazole derivatives are desirable synthetic targets with a range of biological activity and are part of certain anti-tumour agents. Solid-supported radical reactions with substituted benzimidazoles were performed under different experimental conditions, including different solvents, three different resins (Wang, Merrifield and Rink) and different radical reagents. 4-Mercaptobenzoic acid moiety served as a traceless linker in radical ipso-substitution reactions of benzimidazole precursors attached to solid-support to construct tri-cyclic and tetracyclic benzimidazole adducts. The solution-phase radical ipso-substitution protocol was quite successfully translated onto solid-support.

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10

Bailey, Jonathan Henry. "Methodology for the synthesis of biologically important molecules." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260164.

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11

Junan, Siti Asiah Ahmad. "Synthesis of O-heterocycles by free radical methodology." Thesis, University of Nottingham, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258235.

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12

McInnes, Campbell. "New methodology for solid phase peptide synthesis." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/12616.

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A novel linker for the solid phase synthesis of peptide amides is described. This linker based on 2-alkoxydibenzocycloheptadiene enables release of the peptide derivative under very mild conditions and is compatible with base labile N-alpha protecting groups. The efficacy of this linker in generating c-terminal peptide amides has been demonstrated in the synthesis of the natural products, little gastrin, big gastrin, substance P and bombesin. Modification of the linker allows peptide hydrazides to be prepared. The use of the linker in producing unprotected peptide hydrazides has been exemplified in the synthesis of the ubiquitin fragments (43-47)NHNH2 and(67-76)NHNH2. Use of the linker for the synthesis of fully protected peptide hydrazides requires further development. Initial experiments indicate that the linker, when appropriately substituted, may also be useful for the solid phase synthesis of fully protected peptide free acids to be used in fragment condensation.

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13

Kitching, Martin S. "Development of methodology for the synthesis of isoindolinone libraries." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247902.

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Stevens, Kiri. "Methodology for the synthesis of NP25302 and other bioactive natural products." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:ae18879e-d75e-4280-ba55-1ae08e64034f.

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Total synthesis of the pyrrolizidine alkaloid NP25302: (+)-NP25302 is an unusual vinylogous urea containing pyrrolizidine alkaloid shown to exhibit cell adhesion inhibition. It was envisaged that this natural product could be accessed by a novel 5-endo-dig cyclisation to construct the pyrrolizidine core, and a Curtius rearrangement to install the vinylogous urea motif. This methodology was first tested on a model system, furnishing nor-NP25302 from L-proline in 12 steps and 9% overall yield. The total synthesis of (±)-NP25302 was completed in 9 steps and 26% overall yield from ethyl 2-nitropropionate using similar methodology. Studies into the stereospecificity of the Au(I)-catalysed cyclisation of monoallylic diols: During the synthesis of (+)-isoaltholactone in the Robertson group, the key Au(I)-catalysed cyclisation was observed to occur with some stereospecificity. Further investigations were therefore conducted into the stereochemical outcome of this reaction using stereodefined allylic alcohols, and from the combined results a mnemonic was proposed to predict the stereochemistry of the products of this reaction. Studies into the total synthesis of ascospiroketals A and B: Investigations were conducted into the total synthesis of the recently isolated natural products ascospiroketals A and B. A second generation synthesis was used to construct advanced intermediates 1 and 2.

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15

Sharples, Gillian. "Development of chiral base mediated asymmetric synthetic methodology and applications in synthesis." Thesis, University of Salford, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395846.

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16

Varela, Ann. "Application of lithiantion-borylation methodology to alkaloid synthesis : total synthesis of (-) -stemaphylline." Thesis, University of Bristol, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730870.

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17

Namvar, Gharehshiran Amir. "High Level Synthesis Evaluation of Tools and Methodology." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177362.

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The advances in silicon technology, as well as competitive time to market, in the recent decade have forced the design tools and methodologies to progress towards higher levels of abstraction. Raising the level of abstraction shortens the design cycle via elimination of details in design specification. One such new methodology is High Level Synthesis (HLS). HLS tools accept the behavioral design in the abstract level as the input and generate the detailed Register Transfer Level (RTL) code. In this thesis project, the HLS methodology is introduced in the design flow and its advantages are outlined. We then evaluate and compare three HLS tools developed by market leading vendors, namely, C-to-Silicon, CatapultC and Synphonycc. To compare the HLS tools, an HLS input is developed for one of the Ericsson’s designs and the generated RTL is compared with the hand-written RTL based on several performance criteria. Thereof, we discuss the choice of the best tool so as to facilitate adoption of HLS in Ericsson’s design flow. At last, capability of the HLS tools in the synthesis of designs with pure control flow is investigated.

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18

Begleiter, Leah E. "Methodology for polymer supported synthesis towards combinatorial chemistry." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq29217.pdf.

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19

Hertz, Erik, and Peter Nilsson. "Parabolic Synthesis Methodology Implemented on the Sine Function." Lund University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-22324.

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20

Rock, Michael Harold. "New methodology for the synthesis of fluorinated aromatics." Thesis, Durham University, 1990. http://etheses.dur.ac.uk/6246/.

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This thesis is concerned with new methodology for the introduction of fluorine atoms, and trifluoromethyl groups into aromatic systems and the following approaches have been adopted: (i) The possibility of selective cleavage of the aryl-silicon bond of aryltrimethylsilanes by elemental fluorine to give the corresponding fluorinated aromatic compound was explored, and competing silicon and hydrogen substitution was observed. The affect of temperature and solvent upon this process was investigated. (ii) Attempts to modify the reactivity of dilute elemental fluorine (10% fluorine/nitrogen) towards aromatic systems at low reaction temperatures were made by the addition of pyridine and substituted pyridines. The effectiveness of this methodology was limited by the reactivity of the pyridine systems towards elemental fluorine.(Hi) The potential electrophilic fluorinating agents N-fluoro-2,3- bis(2H hexafluoropropyl) pyrrolidine and N-fluorosuccinimide have been synthesised by the direct fluorination of the corresponding N-trimethyl- silyl compounds.(iv) The cycloaddition reactions of hexafluorobut-2-yne with furan and 2-substituted furans have been employed to synthesise a series of benzenoid and heteroaromatic compounds containing two trifluoromethyl groups in high yield.(v) The synthesis of trifluoromethylpyridines by the cycloaddition of 3,3,3-trifluoropropene with oxazoles has also been investigated.

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21

Mason, Joanne Sheri. "Fluorescent tag methodology in enzyme-catalysed oligosaccharide synthesis." Thesis, University of Warwick, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342692.

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22

Lim, Stephen E. L. "A high-level methodology for VHDL-based synthesis." Thesis, University of Aberdeen, 1992. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU047338.

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A language-based design methodology for the design of digital electronic circuits has been developed and implemented. The methodology is suitable for the high-level synthesis of Very Large Scale Integrated (VLSI) circuits, which are specified behaviourally in an IEEE standard hardware description language, VHDL. The output is a register-transfer level specification of the same circuit, with a bound hardware structure that meets the designer's area and speed requirements. We believe that this work is the first high-level synthesis research to preserve VHDL simulation semantics. To this end, we have developed a process model based on the VHDL process statement onto which all behavioural descriptions can be mapped. The synthesis methodology is based on two major sets of transformations: behavioural transformations and control/data flow graph (CDFG) transformations. The first employs several known language compiler optimisation techniques with a goal to minimising data path and controller area, or making user-directed tradeoffs between data path and controller area for an improved speed. CDFG transformations are the workhorse of data path and control synthesis. A graph notation and algebra are developed that support efficient algebraic graph transformations. Data path and control synthesis algorithms that operate on our CDFG model, the VHDL Intermediate Graph (VIG), are presented. Examples from the High-Level Synthesis Workshop benchmark suite are synthesised and results shown. To round up the work, several problems and issues that face high level synthesis both in research and in the real world are discussed in this thesis.

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23

Sharma, B. "Design and tactics towards synthesis of 10 & 14-membered macrocyclic lactones and lewis acid mediated regioselective C-C bond formation." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2017. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/4264.

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The thesis hereby presents a unique perspective for retrosynthetic design and state-of-the-art strategies towards enantioselective synthesis of 10 and 14-membered macrolactones, along with the development of Lewis acid mediated scalable methods for C−C bond formation.
CSIR-SRF
AcSIR

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24

Wu, An-hsiang. "Syntheses of Highly Strained Energetic Molecules and Development of New Synthetic Methodology." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc331132/.

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The objective of this study was to synthesize new energetic, strained, saturated polycyclic compounds. For this purpose, new methodology has been developed, as follows: (i) Ketenes have been generated in situ via treatment of aldo-, keto- or alkenoic acid with either toluenesulfonyl chloride or 2-chloro-1-methylpyridfniurn iodide (Mulkaiyama's reagent). The reactive intermediates thereby generated have been found to undergo intramolecular [2+2] cycloaddition reactions in these systems.

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25

Chandan, Nandkishor Shankarrao. "Novel methodology for synthesis of trisubstituted pyrrolidines : application towards the synthesis of kaitocephalin." Thesis, University of Oxford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543061.

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26

Liang, Huan. "Methodology for natural product synthesis : sordarin, himandrine and lepadiformine." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/14570.

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Fungal infection, of small concern in healthy individuals, can become problematic in immunosuppressed patients with illnesses such as AIDS, and the search for substances that exert antifungal action by new mechanisms continues. A noteworthy group of potent antimycotic natural products known as the sordarins meet this criterion. In order to investigate the effect of various functional and skeletal changes to sordarin on anti-pathogenic activity, we have devised practical, expeditious, and efficient routes to analogs of the natural product. The bioactivity of the new compounds against various pathogenic fungi was evaluated. This research constitutes the first half of my doctoral dissertation. The second half of my work centers on the development of a practical method for the oxidative amidation of phenols. This reaction achieves the conversion of phenols into spirocyclic (sulfon)amido-dienones. The new methodology forms the centerpiece of envisioned syntheses of (±)-himandrine and (-)-lepadiformines. Himandrine, isolated from the bark of Galbulimima belgraveana, displays anticholinergic activity and is thus of potential interest for the treatment of a number of human ailments. Our himandrine skeleton synthesis centered on a tandem oxidative amidation and Diels-Alder reaction, using three different approaches. The alkaloid (-)-lepadiformines displays potency as a potassium channel blocker. Our synthetic study towards this substance utilizes the oxidative cyclization of a phenolic sulfonamide as the key step. The resulting dienone is then desymmetrized through a stereoselective Michael addition leading to an enantiopure tricyclic intermediate, to which hydrocarbon side chain was appended in high yield. Further elaboration will lead to the natural product.

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27

Pandya, Rina. "Methodology towards the synthesis of aryl & heteroaryl sulfoamides." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412632.

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28

Miles, Timothy J. "Synthesis of amino alcohols using a reductive alkylation methodology." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289405.

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Sunderam, V. S. "A methodology for the synthesis of network protocol software." Thesis, University of Kent, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372773.

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30

Brooks, Steven Halton. "Studies in methodology toward the synthesis of natural products." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385612.

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31

Rae, Alastair. "New methodology for the synthesis of homochiral unsaturated amines." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300661.

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32

Lizos, Dimitrios. "Development of free radical methodology for natural products synthesis." Thesis, University of Strathclyde, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273786.

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33

Peacock, Lucy. "Novel methodology for the synthesis of isoindole derived heterocycles." Thesis, University of Bath, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.629658.

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This thesis presents research into the development of a novel conjugate-addition/cyclisation methodology for the synthesis of isoindole derived nitrones. To begin, a review of the principle methods for synthesising nitrones is reported, followed by a discussion of the current uses of nitrones and the requirement for straightforward syntheses of nitrones contained within an isoindole scaffold. The synthesis of an aryl cyclisation substrate possessing the key ortho- relationship between an alpha,beta-unsaturated ester and formyl group is then described. The planned conjugate-addition/cyclisation reaction using hydroxylamine was carried to afford a different nitrone structure to that expected, which was later confirmed by X-ray crystallography. A full discussion of the work undertaken to elucidate the compound structure and to probe the reaction mechanism is reported. A monocyclic nitrone reported in the literature was thought to have been synthesised according to a 1,3-azaprotio cyclotransfer mechanism. Application of the newly discovered conjugate-addition/cyclisation protocol to a linear substrate successfully afforded this monocyclic nitrone, leading us to propose our mechanism as a plausible alternative. Exploration of the scope and limitation of the nitrone forming reaction afforded total of fourteen isoindole derived nitrones. Applying the protocol to modified cyclisation substrates afforded five dihydroisoquinoline derived nitrones and a bicyclic hydroxamic acid also. Research into the reactivity of isoindole derived nitrones is then presented. Varying degrees of success were obtained, largely due to the fact that the substrate does not react as a nitrone, but as its isoindole tautomer. An attempted 1,3-dipolar cycloaddition reaction with tert-butyl acrylate instead afforded a bridged hydroxylamine product, synthesised by a [4+2] Diels-Alder cycloaddition reaction. The final part of this thesis reports the application of the [4+2] cycloaddition reaction between nitrone and an alkyne as a novel route for the synthesis of substituted naphthalenes.

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34

Milich, David Albert. "A methodology for the synthesis of robust feedback systems." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14548.

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35

O'Hora, Paul. "Novel methodology towards the total synthesis of Pseudopterogorgia metabolites." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13437.

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In 1982, routine screening of the Pseudopterogorgia elizabethae stirred the scientific community by showing the presence of cytotoxic metabolites with antimicrobial activity. Since this discovery a vast amount of research has been conducted in synthesising metabolites of the soft coral. Herein we report the developments towards the synthesis of two metabolites (+)-Erogorgiaene and (+)-Elisabethadione utilising three key reactions in setting up the molecules three chiral centres. The use of asymmetric allylation, oxy-Cope rearrangement and cationic cyclisation was utilised to set up the desired stereocentres from a starting cinnamyl aldehyde. Natural elisabethadione was synthesised in a racemic form as a 2:1 mixture of diastereoisomers at the C-13 stereocentre.

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36

Wahedy, Kanan Mahmoud. "Methodology for synthesis of novel bis-and oligo (benzimidazoles)." Thesis, University of Manchester, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.684999.

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37

VIJAY, VIKAS. "A TOP-DOWN METHODOLOGY FOR SYNTHESIS OF RF CIRCUITS." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1100584283.

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38

Dillon, David Lawrence. "Peptide derivatives as pharmaceuticals : synthesis and reactions of n-thioacyl peptides." Thesis, Oxford Brookes University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327912.

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39

Deaton, Timothy Maxwell. "A Boron Alkylidene-Alkene Cycloaddition Reaction: Application to the Synthesis of Aphanamal." Thesis, Boston College, 2017. http://hdl.handle.net/2345/bc-ir:107597.

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Thesis advisor: James P. Morken
Described herein is the exploration of a novel methodology whereby boronate-ester bearing cyclopentanes are produced by reaction between an unactivated olefin and what is described as a boron alkylidene. The mechanism is evaluated and concluded to proceed through a boracyclic intermediate that is achieved by a closed-shell, carbanion addition to the olefin. This mechanistic conclusion is arrived upon by considering two likely alternative routes (an open-shell, radical cyclization and a [2+2] concerted process) and providing evidence to refute them. A reaction scope is established as well as the utility of the methodology through the racemic synthesis of a natural sesquiterpene: aphanamal. Finally, the future of the reaction development will be considered by providing a single example of a 6-endo cyclization
Thesis (MS) — Boston College, 2017
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry

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40

Mciteka, Lulama Patrick. "Novel applications of Morita-Baylis-Hillman methodology in organic synthesis." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1007598.

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The overall approach in the present investigation has been to explore applications of the Morita-Baylis-Hillman (MBH) reaction in asymmetric synthesis and in the continuation of systems with medicinal potential. To this end, a series of varied camphor-derived acrylate esters was prepared to serve as chiral substrates in asymmetric Morita-Baylis- Hillman reactions. Reduction of N-substituted camphor-10-sulfonamides afforded the 3- exo-hydroxy derivatives as the major products. Acylation of the corresponding sodium alkoxides gave the desired 3-exo-acrylate esters, isolation of which was complicated by concomitant formation of hydrochlorinated and diastereomeric competition products. Bulky camphorsulfonamides containing alkyl, dialkyl, aromatic and adamantyl groups were selected as N-substituents with the view of achieving stereoselective outcome in subsequent MBH reactions. The synthesis of novel camphor-derived Morita-Baylis-Hillman adducts using various pyridine-carboxaldehydes proceeded with exceptionally high yields with diastereoselectivities ranging from 7-33 % d.e. Both 1D and 2D NMR and HRMS techniques were employed to confirm the structures and an extensive study of the electropositive fragmentation patterns of a number of camphor-derived chiral acrylate esters was conducted. Attention has also been given to the application of MBH methodology in the construction of heterocyclic ‘cinnamate-like’ AZT conjugates which were designed to serve as dualaction HIV-1 integrase-reverse transcriptase (IN-RT) inhibitors. A number of pyridine carboxaldehyde-derived MBH adducts were synthesized using methyl, ethyl and t-butyl acrylates in the presence of 3-hydroxyquinuclidine (3-HQ) as catalyst. The yields for these reactions were excellent. The resulting MBH adducts were acetylated and subjected to aza-Michael addition using propargylamine. The resulting alkylamino compounds were then used in ‘Click reactions’ to form the targeted AZT-conjugates in moderate to excellent yield. In silico docking of computer modelled AZT-conjugates into the HIV-1 integrase and reverse transcriptase enzyme-active sites and potential hydrogen-bonding interaction with active-site amino acid residues were identified. The electrospray MS fragmentations of the AZT and the novel AZT-conjugates were also investigated and common fragmentation pathways were identified.

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41

Korkmaz, Cokol Nalan. "Development Of The Methodology For The Synthesis Of Bis-aminoinositols." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613580/index.pdf.

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Cyclitols are cyclic compounds having hydroxyl groups which attached to different carbons on the ring. Cyclitols have attracted a great deal of attention for having diverse biological activities. Cyclic alcohols play an important role in biological processes such as inhibition of glycosidase, cellular recognition, and signal transduction. In addition to this, these compounds are very important molecules due to being capable of using while synthesizing natural products or pharmaceuticals. In this study, development of new methodology for the synthesis of bis-aminoinositol derivatives was aimed. The starting material, cis-diester, was synthesized from the Diels-Alder reaction of furan and maleic anhydride followed by reaction with MeOH. As a second key compound, trans-diester was obtained from the Diels-Alder reaction of furan and fumaryl chloride followed by esterification. The diester functionality in these two compounds was planned to be converted into the hydrazide upon treatment with hydrazine monohydrate. Before this reaction, double bond was protected via stereo selective oxidation reaction with m-CPBA due to preventing retro Diels-Alder reaction. Then, hydrazide functionality was converted into acyl azide through &beta
-nitroso hydrazide intermediate. Subsequent Curtius rearrangement reaction resulted in the formation of the isocyanate which was converted to the corresponding bis-urethane by treatment with MeOH. Attempt to cleave the oxa-bridge in urethane with sulfamic acid provided the unexpected tricyclic product 148. Furthermore, hydrolysis of isocyanate with aqueous HCl formed the diamine 156. However, O-bridge could not be opened with any reagents used for that of urethane derivative as described above. Then,the cis-diol 157 was synthesized to prevent the neighboring group participitation during the epoxide-opening reaction. Further ring-opening reactions are under investigation.

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42

Chiu, Min-Sen. "A methodology for the synthesis of robust decentralized control systems." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/11314.

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43

Burrows, Jeremy N. "Free radical methodology and approaches to the synthesis of roseophilin." Thesis, University of Oxford, 1996. http://ora.ox.ac.uk/objects/uuid:a2bd60aa-c369-4412-aea1-d93a6eab07db.

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The homolytic Brook rearrangement is discussed and homolytic fragmentations of epoxides and epoxysilane chemistry are reviewed. Thiyl radical induced isomerisation was performed on spiro alkenylepoxysilanes to generate novel alkenyl-α-trimethylsilylaldehydes rather than the products of radical Brook rearrangement. The trimethylsilylaldehydes were shown to isomerise on heating to silyldienol ethers and, via the addition of a Grignard reagent, to act as stereoselective vinyl cation equivalents. Attempts to extend the scope of the isomerisation to non-rigid systems met with failure. A review of the antibiotic Roseophilin is presented. Cycloaddition-fragmentation approaches to medium and large rings are reviewed as a prelude to our first route, the proposed Michael addition-retro-aldol fragmentation of the Diels-Alder adduct derived from isopropyl-cyclopentadiene and cyclodec- 2-yn-1-one. The novel ynone, synthesised via the intramolecular Friedel-Crafts acylation of 10-trimethylsilyl-9-decynoyl chloride, was found to isomerise readily to bicyclo[4.4.0]dec-1(6)-en-2-one therefore the model Diels-Alder reaction with cyclopentadiene was effected in one-pot from the cyclisation precursor. Details of the attempted fragmentation of tricyclo[10.2.1.0^2,11]pentadeca-2(11),13-dien-3-one are then described but, due to inconclusive results, an alternative study was instigated. The use of free-radical macrocyclisations in the synthesis of large rings is reviewed with particular reference to the synthesis of natural products. Three strategies for the formation of a bicyclo[10.2.1]pentadecanone skeleton are reported, and subsequent model studies described. Cuprate additions to vinyl lactones and epoxides are discussed. The preferred strategy, involving a cycloalkyl tether between the radical donor and radical acceptor groups, was extended to a system which was derived from the addition of various cuprates to 2-oxabicyclo[3.3.0]oct-7-en-3-one The preparation of cuprates derived directly from 6-iodohexan-1-ol and 1-chloro-6-iodohexane is described. The trans- cuprate addition products were converted successfully to bicyclo[10.2.1]pentadec-12-en-3-one, and the cis- analogues, accessible through a novel regio- and stereoselective hydroboration-fragmentation reaction of 7- (6'-chlorohexyl)-2-oxabicyclo[3.3.0]oct-7-en-3-one, led to bicyclo[10.2.1]pentadec- 13-en-3-one. The successful cyclisations of model oximes, to form nitrones having the correct connectivity for the third ring of Roseophilin, are described. Cuprate additions to 6-(1'-methylethyl)-2-oxabicyclo[3.3.0]oct-7-en-3-one resulted in anti- attack; the cis- adducts were inaccessible via the above methodology but a few intermediates in the trans- series were prepared. Future routes and modifications to the methods developed are then discussed.

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44

McGonagle, Alison Elizabeth. "Synthesis of nitrogen-containing heterocycles using novel aza-Wittig methodology." Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439563.

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45

Pugh, Matthew David. "New methodology for the synthesis of trioxane based antimalarial compounds." Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288195.

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46

Parmar, Rakesh. "New methodology for the synthesis of enantiopure [2.2]paracyclophane derivatives." Thesis, University of Sussex, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436227.

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47

Bremner, Murray Alexander. "The development of methodology for the chemical synthesis of oligonucleotides." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/15358.

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The development of novel protecting group strategies for the 2'-hydroxyl function of ribonucleosides has been reviewed and a new design has been formulated. The design is based upon a two stage deprotection strategy which is compatible with the final steps in RNA synthesis using solid phase methods. Central to this is the intramolecular addition to an acetylenic system leading to an acid-labile enol ether system, collapse of which results in liberation of the 2'-hydroxyl function. A series of propargyl based systems have been synthesised, incorporated and their suitability evaluated for the automated chemical synthesis of oligoribonucleotides using the phosphoramidite approach. Also discussed are the fully automated syntheses of branched oligodeoxynucleotides (ODNs), accomplished using a 5',2'-di(dimethoxytrityl)-protected arabino-uridine derivative as the branching monomer. The synthesis and incorporation of the branching monomer has been described. The affinities of the branched ODNs towards complementary single stranded ODNs were studied using UV thermal denaturing experiments.

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Hesse, Matthew James. "The diastereodivergent synthesis of polysubstituted alkenes through lithiation-borylation methodology." Thesis, University of Bristol, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.633254.

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49

Engel, Douglas A. "Organic synthesis and methodology related to the malaria drug artemisinin." Tallahassee, Fla. : Florida State University, 2009. http://etd.lib.fsu.edu/theses/available/etd-07092009-100014/.

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Thesis (Ph. D.)--Florida State University, 2009.
Advisor: Gregory B. Dudley, Florida State University, College of Arts and Sciences, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Sept. 28, 2009). Document formatted into pages; contains xi, 242 pages. Includes bibliographical references.

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50

Taggi, Andrew Edmund. "The development of novel methodology for catalytic asymmetric synthesis ketenes." Available to US Hopkins community, 2003. http://wwwlib.umi.com/dissertations/dlnow/3080776.

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Dissertations / Theses on the topic 'Methodology of synthesis'

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