Dissertations / Theses: 'Synthetic'

1

Coates, Helen Margaret. "Synthetic studies towards stemofoline synthesis." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238730.

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Foley, Michael Andrew. "1-Acyldihydropyridones as Synthetic Intermediates." DigitalCommons@USU, 1988. https://digitalcommons.usu.edu/etd/7180.

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The most efficient and stereoselective total synthesis of (+/-) lausbine II to date has been achieved. The key steps in this are the copper-mediated conjugate addition reaction of the Grignard reagent of 1-bromo-4-chlorobutane to a dihydropyridone and a stereoselective reduction of a quinolizidinone. Methodology has been developed for the convenient synthesis of 1-acyl-2-substituted-1,2,5,6-tetrahydropyridines. This was accomplished by adding novel alkylzinc iodides to the 1-acyliminium ion derived from Nphenoxycarbonyl-4-methoxy-1, 2, 3, 4-tetrahydropyridine.

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3

Hale, Joshua G. "Biomimetic motion synthesis for synthetic humanoids." Thesis, University of Glasgow, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270966.

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4

Liu, Yunqi. "Synthetic approaches toward natural product synthesis." Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187050.

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1,2-Dithiolan-3-one-1-oxide exists in antihumor antibiotic leinamycin and can cause DNA cleavage in the presence of thiols. Diastereoselective synthesis of this unique ring system has been achieved by low temperature oxidation of the corresponding 1,2-dithiolan-3-ones with 3,3-dimethyldioxirane. 5-Methyl-1,2-dithiolan-3-one-1-oxides were synthesized by oxidation of 5-methyl-1,2-dithiolan-3-one with 3,3-dimethyldioxirane. Eu(fod)₃ and C₆D₆ induced proton chemical shift studies showed that the major isomer in the product has a trans sulfoxide relative to the 5-methyl group. Low temperature oxidation of 4-substituted-amino-5,5-dimethyl-1,2-dithiolan-3-ones by 3,3-dimethyldioxirane preferentially led to the corresponding trans-1,2-dithiolan-3-one-1-oxides. This assignment was made on the basis of a X-ray crystallographic structure study. Formation of azlactones as well as 1,2-dithiolan-3-one-1,1-dioxide were also observed when some substituted 1,2-dithiolan-3-ones were oxidized by 3,3-ditnethyldioxirane. Three 2,2-dimethyl-1,3-dithian-4-ones were synthesized by SnCl₄ mediated condensation of β-mercaptothioacids and acetone. Oxidation of 2,2,6-trimethyl-1,3-dithian-4-one with Ce(IV) did not give 1,2-dithiolan-3-one or 1,2-dithiolan-3-one-1-oxides as anticipated; 1,3-dithian-5-en-4-one was detected as the product instead. Synthetic approaches toward loline were explored. Intramolecular photoaddition of bicyclic olefinic N-nitrosamine did not give the desired product. An epoxide approach did not furnish loline due to unsuccessful epoxide ring opening by azide ion. In the urea approach, the tertiary nitrogen of the bicyclic urea preferentially undergoes a transannular iodocyclization. The same results were obtained by halocyclizing bis-silylimidate or mono-silylimidate of the bicyclic urea.

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5

Stewart, Mark Richard. "The design and synthesis of synthetic receptors." Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400852.

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6

Swenson, Helen Rachel. "Studies in synthetic peptides and heterocyclic synthesis." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/13061.

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The following work documents three studies undertaken using solid phase synthesis techniques. Interaction of the zinc metalloprotease, endothelin converting enzyme-1(ECE-1), with its peptidic natural substrate big endothelum-1 has been investigated via an SAR study, using solid phase peptide synthesis (SPPS). Truncated forms of the substrate had been previously reported to inhibit ECE-1, this was confirmed however the big ET-1 analogues were shown to be substrates for the enzyme. A short study of the substrate specificity of ECE-1 was carried out. The synthesis of vast libraries of peptides using combinational synthesis has been used to accelerate the drug discovery process. Purification of these mixtures has not been previously attempted. 17-Tetrabenzo [a,c,g,i]fluoroeneyhethoxycarbonyl (Tbfmcc) developed for use with single peptides of proteins, has been used to achieve facile purification of five peptide libraries synthesised using SP. The methodology was fully optimised for the efficient separation of the desired library members from all impurities by exploiting the affinity of TBfmoc for carbon. A potential small molecule inhibitor of the zinc metalloenzyme, farnesyl transferase (FTase), was designed. The efficient solution phase synthesis of this novel structure is reported its adaptation to solid phase synthesis is described, with the view to using multiple parallel synthesis techniques to synthesise a range of analogous.

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7

Scott, Felicia Yi Xia. "Controlled Hybrid Material Synthesis using Synthetic Biology." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/86147.

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The concept of creating a hybrid material is motivated by the development of an improved product with acquired properties by amalgamation of components with specific desirable traits. These new attributes can range from improvements upon existing properties, such as strength and durability, to the acquisition of new abilities, such as magnetism and conductivity. Currently, the concept of an organic-inorganic hybrid material typically describes the integration of an inorganic polymer with organically derived proteins. By building on this idea and applying the advanced technologies available today, it is possible to combine living and nonliving components to synthesize functional materials possessing unique abilities of living cells such as self-healing, evolvability, and adaptability. Furthermore, artificial gene regulation, achievable through synthetic biology, allows for an additional dimension of the control of hybrid material function. Here, I genetically engineer E. coli with a tightly controlled artificial protein construct, allowing for inducible expression of different amounts of the surface anchored protein by addition of varying concentrations of L-arabinose. The presence of the surface protein allows the cells to bind nonliving nanoparticle substrates, effectively turning the cells into living crosslinkers. By using the living crosslinker, I was able to successfully synthesize a robust, macroscale living-nonliving hybrid material with magnetic characteristics. Furthermore, by varying the particle size and inducer concentration, the resulting material exhibited alterations in structure and function. Finally, I was able to manipulate material kinetics within a PDMS channel by applying fluctuating magnetic fields and demonstrate material durability. These results demonstrate the ability to manipulate synthesis of living-nonliving hybrid materials, which demonstrate the potential for use in promising applications in areas such as environmental monitoring and micromachining. Additionally, this work serves as a foundational step toward the integration of synthetic biology with tissue engineering by exploiting the possibility of controlling material properties with genetic engineering.
Ph. D.

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8

Kim, Charles. "Synthetic studies toward the synthesis of norrisolide /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2002. http://wwwlib.umi.com/cr/ucsd/fullcit?p3055785.

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9

Siddiq, Musab. "Synthetic Instruments an overview : Synthetic Instruments." Thesis, University of Gävle, Department of Technology and Built Environment, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-340.

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The rapid development within the field of measurement methods and techniques and software design that has taken place over the last years offers new possibilities for designers of measurement systems through the use of virtual instruments as building blocks. The concept of virtual instrumentation is developed within the interchangeable virtual instrument foundation. A closely related term is “synthetic instruments”, which is often used for essentially the same concept, but it is even more software oriented. Synthetic instruments as a research field are in an initial stage and a quick search on “Synthetic instruments” in Institute of Electrical and Electronics Engineers (IEEE) explorer match close to 30 documents. IEEE explorer is a database that provides full-text access to IEEE transactions, journals, magazines and conference proceedings, and all current IEEE Standards.

This Master Thesis is a theoretical work extracted from study material, IEEE documents and web-resources referenced. The work gives the reader an overview of the Synthetic Instruments and their functionality with respect to hardware and software. The papers were analyzed based upon the various trends in the research, development and productizing phases.

For this approach; kernel architecture of an ideal synthetic instrument has been introduced as a prototype around which current technologies and applications can be addressed. The major areas of focus in the architecture are the data conversion and signal conditioning; the knowledge of its working under current implemented technologies has been highlighted and discussed in regards to the software and hardware trends. The defense industry holds the major influence.

The work was aimed towards giving a state-of-the art introduction to synthetic instrument technology; also in order to provide the work an introductory nature, only one hardware & software example has been discussed.

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10

Gilmore, Laurie Ann. "Chlorination of synthetic dyes and synthetic brighteners." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/20794.

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11

Rivas, Fatima R. "Synthetic studies towards the total synthesis of norzoanthamine." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3221252.

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Thesis (Ph. D.)--University of California, San Diego, 2006.
Title from first page of PDF file (viewed September 8, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.

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12

Rahn, Volker Siegfried. "Synthetic studies towards the total synthesis of (-)-alstonerine." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401724.

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13

Wild, Mark. "Synthetic studies towards the synthesis of spongistatin 1." Thesis, Bangor University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310863.

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14

Zha, Huiyan, and 查慧艳. "Design, synthesis and characterization of synthetic ion transporters." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hdl.handle.net/10722/206532.

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In recent decades, small molecules have been widely applied to the generation of functional ion transporters. Major discoveries disclosed in this thesis include a self-assembled chloride-dependent potassium channel candidate, a physiological chloride and bicarbonate dual-transporter, and a series of efficient synthetic ion transporters. In nature, K+ channels play an important role in Ca2+ signaling, volume regulation, secretion, proliferation, and migration. The extracellular K+ concentration (4 mM) is about 40 times lower than the intracellular K+ concentration (160 mM). The opening of K+ channels consequently generates an efflux of positive charge, which hyperpolarizes or repolarizes the cellular membrane. In this research, by using fluorescence assays, NMR and patch clamp experiments, compound ZHY-CM23 was found to self-assemble into a chloride-dependent K+ selective channel mediating K+ transport across lipid bilayers and cell membranes. In addition, the synthetic K+ channel formed by ZHY-CM23 was found to be capable of generating and modulating the membrane potential of liposomes and to significantly hyperpolarize the resting membrane potential of HEK 293 cells. This finding provides new insight into developing drugs for the treatment of severe human diseases caused by K+ channel malfunction, such as arrhythmia, neurological disorders and autoimmune diseases. Cystic fibrosis is a chronic recessive disease resulting from the loss of function mutations in the gene encoding of the cystic fibrosis transmembrane conductance regulator (CFTR), a member of the ABC family of membrane transporters. Recent findings reveal that restoring bicarbonate transport might be useful for the treatments of the underlying defect in cystic fibrosis. On the basis of fluorescence assays, NMR and short circuit current experiments, the small molecule ZHY-CM11 has been discovered to not only act as a bicarbonate transporter in lipid membranes, but also to induce chloride-dependent bicarbonate secretion in cultured calu-3 epithelia. It is a promising lead compound to be developed for the treatment of cystic fibrosis and other diseases related to chloride and bicarbonate transport defects. Through structural modifications on the bioactive ion channels and the transporters ZHY-CM23 and ZHY-CM11, some valuable information on the structure-activity relationship has been obtained, and a series of potentially biologically applicable synthetic ion transporters have been discovered.
published_or_final_version
Chemistry
Doctoral
Doctor of Philosophy

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15

Viseux, Eddy Michel Elie. "Synthetic studies towards a total synthesis of roseophilin." Thesis, University of Sussex, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420509.

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16

Charles, Mark David. "Synthetic studies toward a total synthesis of morphine." Thesis, University of Sussex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272077.

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17

Turvill, Michael W. "The synthesis of natural and synthetic colouring materials." Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280103.

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18

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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19

Scott, Richard. "Synthetic approaches towards the synthesis of phorbol esters." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314251.

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20

Scott, Karen Ann. "Synthetic studies related to the synthesis of vincristine." Thesis, University of Strathclyde, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367067.

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21

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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22

Spoors, Paul Grant. "New synthetic approaches towards the synthesis of morphine." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330148.

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23

Thom, Catriona. "Synthetic methods directed towards the synthesis of rapamycin." Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241117.

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24

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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25

Clark, Jonathan. "New synthetic methods towards the synthesis of taxanes." Thesis, University of Leicester, 1994. http://hdl.handle.net/2381/34051.

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This thesis is a continuation of previous work done in the Jenkins group to produce taxanes from glucose. The reactions investigated by R. Bonnert and J. Howarth are improved upon to enable the large scale synthesis of the diol (1). After the successful protection of (1) with two tert-butyldiphenylsilyl protecting groups the benzylidene ring was opened by bromination with N-bromosuccinimide. This compound then underwent fragmentation with zinc metal to open the acetal ring and yield the highly functionalised key intermediate chiral cyclohexane (2). This aldehyde was then reduced with sodium borohydride and protected with a triethylsilyl group. The alkene side chain underwent ozonolysis cleanly followed by the addition of lithium-2,2,3,3-tetramethyl-bromocyclopropane. The cyclopropane addition was improved upon by the addition of cerium trichloride. Compounds (3) were isolated from this reaction and a series of studies were done to test the viability of these compounds to undergo further reactions, in particular to rearrange to give dienes. Compounds with bromine in were found to rearrange and those with chlorine in did not. It is believed that most of this work was done with compounds containing chlorine, although at the time this was not realised. Detailed spectroscopic studies verified the stereostructures as those desired for taxanes at the key chiral centres. Alternative sugar routes were also considered and this work gave rise to a new Robinson reaction on a carbohydrate, to give compound (4). Unfortunately this compound was found to have the wrong stereostructure for the synthesis of taxanes from it.

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26

Chen, Yong. "Synthetic Studies on Total Synthesis of Azaspiracid-3." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1385895424.

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27

Cafiero, Lauren. "New synthetic applications of trichloromethyl carbinols in synthesis." Thesis, [Tuscaloosa, Ala. : University of Alabama Libraries], 2009. http://purl.lib.ua.edu/112.

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28

Singh, R. "Carbohydrate functionalized synthetic elastomers: synthesis, characterization and applications." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2010. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3739.

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29

Boland, Howard. "Art from synthetic biology." Thesis, University of Westminster, 2013. https://westminsterresearch.westminster.ac.uk/item/8yyq5/art-from-synthetic-biology.

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30

Barnard, Jonathan Harold. "Synthetic retinoids." Thesis, Durham University, 2010. http://etheses.dur.ac.uk/288/.

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Chapter one is split into three sections, providing general overviews of synthetic retinoids and their biology, Pd-catalysed C-C bond forming reactions and transition metal-catalysed borylation of aromatic and vinylic C-H bonds, respectively. Chapter two details the application of sequential Ir-catalysed aromatic C-H borylations, Pd-catalysed C-C bond forming reactions and Rh-catalysed vinylic C-H borylations for the stereo-controlled synthesis of stilbene-based TTNPB retinoids. Chapter three details the application of Ir-catalysed aromatic C-H borylations, Sonogashira cross-couplings and Suzuki-Miyaura cross-couplings for the synthesis of tolan-, and biaryl-based retinoids. Chapter four details the development and applications of new RhI catalyst precursors for the dehydrogenative borylation of unactivated olefins. The dehydrogenative borylation reactions were utilised in one-pot, single solvent syntheses of 2-arylindenes from indene and arylhalides through C-H borylation and subsequent Suzuki-Miyaura cross-couplings.

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31

Rosser, Mark Joseph. "Synthetic receptors." Thesis, Durham University, 1993. http://etheses.dur.ac.uk/5761/.

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Novel, rigid cyclophanes have been designed and synthesised as receptors for the biologically important neurotransmitter, acetyl choline. The receptor cavities were less symmetrical than those of similar cyclophanes which had been previously prepared, as they incorporated two quite different functional groups on opposite sides of the cavity. NMR experiments indicated that a cyclophane which incorporated a benzoate residue bound acetyl choline, with an exchange between the free and bound species which was slow on the NMR time scale. A second cyclophane, which incorporated both a benzoate and a pyridinium residue, also bound acetyl choline, but the exchange between the free and bound species was fast on the NMR time scale. NMR experiments also indicated that a third cyclophane, which incorporated only uncharged pyridyl and benzyl residues, did not bind acetyl choline. However, acetyl choline was efficiently transported across a PVC membrane by this neutral cyclophane with very little interference from ammonium and group I and group II metal cations. Urea and thiourea residues were incorporated into crown-type macrocyclic frameworks. The crystal structures of two macrocycles incorporating thiourea residues (18N(_4)O(_2).2CS and 24N(_4)O(_4).2CS) were determined, as was the crystal structure of the 18N(_4)O(_2).2CS/silver(I) complex. Preliminary experiments indicate that the bisthioureas 18N(_4)O(_2).2CS and 24N(_4)O(_4).2CS form quite stable complexes with the 'soft' metal cations silver (I), zinc (II), cadmium (II) and mercury (H), and that the analogous bisureas 18N(_4)O(_2).2CO and 24N(_4)O(_4).2CO form stable complexes with sodium and potassium, for which they are selective.

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32

Watlington, John A. (John Andrew). "Synthetic movies." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/70623.

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33

Jordan, Benjamin Thomas. "Synthetic Landscapes." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4303.

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My work explores the complex social geography of modern society and the intricate relationship between mankind and the environment. Through this work I explore the past and present lineage of manifest destiny, from its beginnings in Europe to western expansion in America, to forms it has takes in contemporary America. These ceramic forms serve as the conceptual grounds to explore the romanticizing of the western landscape especially from an individual and group perspective. I simultaneously celebrate the history of the pastoral life while questioning the authenticity, and motivations of that lifestyle, and use this platform as a jumping off point to ask questions about humanities complicated relationship with nature. Through hand-labor, contemplative making, and a reverence for tradition, I explore both interrelated and divergent human perceptions using clay as my primary medium.

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34

Blum, Janna Karen. "Broadening the enyzme-catalyzed synthesis of semi-synthetic antibiotics." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39528.

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An alpha-amino ester hydrolase (AEH) applicable to synthesis of semi-synthetic antibiotics was cloned from the genomic DNA of Xanthomonas campestris pv. campestris sp. strain ATCC 33913. AEHs catalyze the synthesis and hydrolysis of alpha-amino beta-lactam antibiotics. The enzyme was characterized for thermodynamic and kinetic parameters. The enzyme shows optimal ampicillin hydrolytic activity at 25C and pH 6.8. The AEH enzymes have been shown to have excellent synthetic capability. Additionally, we demonstrated the first fully aqueous enzymatic one-pot synthesis of ampicillin direct from the natural product penicillin G eliminating the isolation of the intermediate 6-APA. Lastly, to improve the thermostability of the AEH a modified structure-guided consensus model of seven homologous enzymes was generated along with analysis of the B-factors from the available crystal structures of the known AEH from Xanthomonas citri. Our best variant, which is a quadruple mutant, E143H/A275P/N186D/V622I, which has a T_50_30, the temperature at which the half-life is 30 minutes, of 34C and 1.3-fold activity compared to wild-type. Overall, we have successfully improved the understanding of the AEH class of enzymes and applied a novel cascade application, demonstrating AEHs unique applicability in the synthesis of beta-lactam antibiotics. The improved thermostability will further improve the industrial relevance of AEHs.

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35

Kundu, Kousik. "Synthesis of highly functionalized diazoacetoacetates and their synthetic applications." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/4103.

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Thesis (Ph. D.)--University of Maryland, College Park, 2006.
Thesis research directed by: Chemistry. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Sreekumar, Sanil. "Synthetic studies towards the total synthesis of lancifodilactone G." Thesis, University of Liverpool, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569566.

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This thesis presents our studies towards the first total synthesis of the novel anti- HIV agent lancifodilactone G, which has a highly unusual aliphatic enol. The first chapter provides a survey of architecturally diverse nortriterpenoids that were isolated from the Schisandraceae family. A proposed biosynthetic pathway for lancifodilactone G and closely related natural products provides a rationale for the formation of the consecutive 7/8/5 fused carbo cycles that are unique to Schisandra nortriterpenoids. Chapter 1 goes on to outline the reported strategies to access the core of lancifodilactone G and concludes with a retrosynthetic analysis proposed by the Evans group, which includes a biosynthetically inspired single-pot polycyclisation reaction. Chapter 2 describes the highly stereocontrolled synthesis of the eastern fragment (F-G rings) using transition metal-mediated Pauson-Khand reaction. This chapter also reviews the metal-mediated diastereoselective Pauson-Khand reaction directed by the stereogenic centre at C2, with the ample illustration to total synthesis. Attempted strategies for the assembly of the bicyclic cyclopentanone motif via a dienyl Pauson-Khand reaction of silicon- and oxygen- tethered diene-enes are presented. The failure of these strategies at different stages of the synthesis resulted in the exploration of a classical Pauson-Khand approach, which successfully furnished the eastern fragment. Finally, a second-generation synthesis is described which provided the fully functionalised eastern fragment with improved efficiency and overall yield. Chapter 3 discusses the successful synthesis of the western fragment (B-C rings) using a diastereoselective [4+3] cycloaddition strategy. Attempted strategies for the synthesis of the key 2,3-disubstituted furan derivative are presented, which was achieved via a hetero Pauson- Khand reaction. This chapter includes a brief account of the classical [4+3] cycloaddition reactions of furans using an in situ generated oxyallyl cation and also employing vinyl carbenoids in the metal-catalysed version. The review also highlights the application of the [4+ 3] cycloaddition reaction in the expeditious assembly of functionalised 7-membered rings that occur in a number of important biologically active natural products. The third chapter goes on to describe the application of these cycloaddition reactions in the synthesis of the fully functionalised western fragment of Lancifodilactone G. Chapter 4 describes a model study aimed at expediting the synthesis of the western fragment using a rhodium-catalysed allylic substitution reaction. A brief mechanistic discussion on unique aspects of the allylic alkylation reaction is illustrated. Chapter 4 concludes by outlining the coupling strategy for eastern and western fragments and the end game studies for the completion of the synthesis of lancifodilactone G.

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Welsh, Emma Jane. "Asymmetric synthesis of aphanorphine and synthetic approaches toward dictyoxetane." Thesis, University of Birmingham, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446335.

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Dunn, Stephen Henry. "Total synthesis of norsegoline : synthetic approaches to the cystodytins." Thesis, University of East Anglia, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238806.

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Crawford, Claire Frances. "Synthetic studies towards a total synthesis of hemibrevetoxin B." Thesis, University of Leeds, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435783.

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Pearson, David James. "Synthetic studies towards the total synthesis of popolohuanone E." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267117.

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41

Shen, Yue. "Design, synthesis and characterization of the synthetic yeast genome." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33182.

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With the rapid development of DNA synthesis technologies, synthetic biology has made tremendous progress in the past 15 years, in particular for synthetic genomics. Synthetic genomics is a nascent field of synthetic biology, which aims to design new biological systems/organisms to satisfy human needs. Conventional synthetic biology focuses on the redesign, construction and modeling of biological parts, pathways or genomes that do not exist in nature, while synthetic genomics encompasses technologies that allow the generation of chemically synthesized larger parts of genomes or whole genomes, with simultaneous redesign of an organism's genetic material. Synthetic genomics is painting a blueprint for a new era of biology and holds great potential for a multitude of applications, such as pharmaceuticals, biofuels and rapid generation of vaccines against emerging diseases. Chapter One gives an introduction of the current state of the art and challenges of synthetic genomics and the objectives of this study. Chapter Two demonstrates the design and construction strategy of two megabase-long synthetic yeast chromosomes, SynII and SynVII. Chapter Three describes the full characterization of SynII and SynVII. Chapter Four introduces the SCRaMbLE (Synthetic Chromosome Rearrangement and Modification by LoxPsym-mediated Evolution) system and its application in SynII and SynVII. Taken together, this work demonstrates the utility of synthetic yeast for understanding biological systems and its potential for industrial applications.

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42

Oswald, Magalie Florence. "Novel synthetic methodologies for the synthesis of heterocyclic rings." Thesis, University of Sussex, 2010. http://sro.sussex.ac.uk/id/eprint/2348/.

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Part 1. Synthesis of Stereodefined Heterocyclic Rings. We wish to report the development of novel methodology for the synthesis of stereodefined heterocyclic rings, which could be used for the synthesis of natural products containing for example tetrahydrofuran motifs, such as members of the pamamycin family. Due to their ambivalent properties, organoaluminium reagents can easily react with acetals by transfering an alkyl group after prior coordination with the substrates. This work has led to the development of a novel cascade reaction. It involves the reaction of acetals with trialkylaluminium reagents, which is followed by a cyclisation reaction, generating consequently tetrahydrofuran or tetrahydropyran rings. In addition, investigation towards the synthesis of pyrrolidines was also carried out. Part 2. Investigation and Development of a Novel Cascade Reaction. The Bergman cycloaromatisation reaction is based on the formation of a biradical intermediate species and has been, over the years, a constant source of inspiration for scientists. Continued efforts over the last 40 years permitted, among other things, a better understanding of the mode of action of the enediyne antibiotics, a class of natural compounds with exceptional biological activities. The Parsons group recently developed a novel cyclisation reaction, which also generates a biradical species, and which could, after being trapped with a suitable alkene, lead to the formation of tricyclic molecules containing heterocyclic cores. As a result, we wish to further investigate this novel reaction and develop a tandem reaction, involving this reaction combined with a Diels-Alder reaction in order to generate pentacyclic molecules, in one synthetic operation, and from an acyclic precursor.

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Vassilaras, Plousia E. "Alternative Synthetic Methodologies for the Synthesis of Organosilicon Compounds." Case Western Reserve University School of Graduate Studies / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=case1310150433.

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Audic, Alexandre. "Synthetic studies towards the total synthesis of hexacyclinic acid." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7790/.

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In the first chapter of this thesis, published works found in the literature about hexacyclinic acid and FR182877 are reported and commented. A quick summary of the previous work done in the Prunet group is also described. In the second and third chapter, a more detailed account of the work undertaken during this PhD was given. Firstly, syntheses of two ABC tricycles incorporating tert-butyl and (trimethylsilyl)ethyl esters were undertaken. These syntheses include two key steps previously developed in the group, a diastereoselective Michael addition and a Snider cyclisation. Multiple conditions for the hydrolysis of the esters were attempted but none of them gave the desired product. The main part of this work is focused on the synthesis of a CDEF model and in particular about the development of the key step, the formation of a nine-membered ring. Several DEF fragments were synthesised in short synthetic sequences and as single isomers. Six different synthetic pathways were developed in total and a novel method, a Michael/elimination reaction, was found to be a very efficient way to close the desired medium-size ring. From the nine-membered ring, regioselective reduction and palladiumcatalysed allylic substitution led to the formation of the CDF tricycle. Final steps of the synthesis were fruitless and led only to decomposition. A synthesis of a chiral C-ring was also developed during this PhD. II Finally, another project was undertaken, not related to hexacyclinic acid. Methodology developed in the group for the diastereoselective formation of trisubstituted alkenes employing a temporary silicon-tethered ring-closing metathesis was extended to homoallylic alcohols. The first steps of the method were similar to the previous methodology but the end-game had to be modified in favour of an oxidation/reduction sequence to successfully obtain the desired products with the correct geometry. In the fourth chapter, procedures and analytical data for the synthesised compounds previously described are reported.

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Booth, Rebecca. "Development of a new synthetic biology tool : synthetic sub-cellular compartments." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/development-of-a-new-synthetic-biology-tool-synthetic-subcellular-compartments(47b90b77-0c64-40f4-965a-e1e2c3d7fb2f).html.

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Methods for the remotely triggered release of biologically active molecules has been an area of intense research in recent years, as it would allow hard-to-obtain biomolecules to be tested in cell-like environments.1 The removal of polar functional groups from hydrophilic structures upon the application of an external stimulus would generate unfunctionalised molecules, which could then participate in amphiphilic self-assembly. This could be used in the release of bioactive molecules and therefore in the in vitro investigation of drug activity. In this PhD project, diazene chemistry was identified as the optimal method for the generation of unfunctionalised compounds through the removal of polar groups since fragmentation takes place rapidly and without the formation of potentially toxic intermediates or by-products. The synthesis of a range of protected hydrazines is described in this thesis (Scheme 1), in addition to the investigation of the rates of decomposition of various simple sulfonyl hydrazides, which led to the isolation of the product of the decomposition of a sulfonyl hydrazide. The photolysis of NVOC- and NPPOC-protected hydrazine derivatives is discussed.

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Gentil, Roxane Mylene Perret. "Synthetic approaches to reniorone synthetic approaches to nor-segoline." Thesis, University of East Anglia, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278220.

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El-Masri, M. "Synthetic studies towards pentalenolactone E and some general synthetic methods." Thesis, University of Southampton, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373974.

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Moore, Christopher Gareth. "Studies towards the synthesis of ptilomycalin A and synthetic analogues." Thesis, Bangor University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310923.

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Baxter, Andrew Douglas. "Enantioselective synthesis of aminotetralins : novel synthetic applications of amino acids." Thesis, University of East Anglia, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359328.

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McLaren, Lee. "Synthetic applications of hypervalent iodine reagents : total synthesis of aranorosin." Thesis, University of East Anglia, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385890.

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Dissertations / Theses on the topic 'Synthetic'

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