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Dissertations / Theses on the topic 'Synthesis of precursor'

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Published: 18 May 2024

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1

Oguzkaya, Funda. "Stereoselective Synthesis Of Optically Active Cyclitol Precursors Via Chemoenzymatic Method And Synthesis Of A Nucleoside Precursor." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/2/12607324/index.pdf.

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ABSTRACT STEREOSELECTIVE SYNTHESIS OF OPTICALLY ACTIVE CYCLITOL PRECURSORS VIA CHEMOENZYMATIC METHOD AND SYNTHESIS OF A NUCLEOSIDE PRECURSOR Oguzkaya, Funda M.S., Department of Chemistry Supervisor: Prof. Dr. Cihangir Tanyeli June 2006, 99 pages &
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-hydroxylated products which are easily racemized, protection was directly adjusted via acetylation so as to prevent this possibility. Resulting enantiomerically enriched products were subjected to Upjohn Dihydroxylation to obtain cyclitol precursors and following Luche Reduction of ketone was adjusted so as to obtain corresponding cyclitols. In addition with such synthetic design, firstly dimethyl cyclopent-3-ene-1,1-dicarboxylate was obtained so as to reach in former manner 3-cyclopentene-1,1-dicarboxylic acid, and in latter manner cyclopent-3-enecarboxylic acid. Resulting compound was converted to 6-iodo-2-oxa-bicyclo[2.2.1]heptan-3-one and followingly to the target nucleoside precursor which is 2-oxa-bicyclo[2.2.1]hept-5-en-3-one.
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2

Starr, Matthew J. "Synthesis of a C5'-Pseudouridinyl Radical Precursor." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1449675404.

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3

Mcausland, Donald Euan Reynolds. "Arynes in synthesis : new reaction and precursor development." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/arynes-in-synthesisnew-reaction-and-precursor-development(1f59c4ec-dc6d-487b-9bc4-c5a99d5bc030).html.

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The arylation of readily accessible N-tosyl hydrazones has been achieved using arynes generated in situ under mild conditions. The resulting N-tosyl-N-aryl hydrazones undergo a one-pot Fischer indole reaction on the addition of acid, giving a synthesis of protected indoles that avoids handling unstable intermediates and arylhydrazines. A new route to functionalised 2-(trimethylsilyl)phenyl triflate aryne precursors via Suzuki cross-coupling has been developed. The method allows the incorporation of a wide range of aryl and heteroaryl groups and reactions of arynes generated from these novel precursors have been demonstrated, including a cyclotrimerisation and a fluorenone synthesis. Work was also undertaken on aryne σ-insertion reactions. The addition of benzyne to ynamides was found to result in its net insertion between the nitrogen and acetylene species. The reaction proceeds from attack at the terminal carbon in an analogous manner to C(sp)–O insertions.
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4

Salavati, Niasari M. "Synthesis of cadmium sulfide nanostructures by novel precursor." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20589.

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5

Vo, Mong Truc. "Synthesis of a Precursor for a Carotenoid Cationic Lipid." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for kjemi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19089.

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The goal of this work was the synthesis of a carotenoid cationic lipid for the research of carriers of nucleic acids into defective cells via transfection therapy. In the course of this project a precursor for the carotenoid cationic lipid was successfully obtained, but because of the limited time the synthesis of the carotenoid cationic lipid itself was not performed.
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6

Alqarni, Saad Ali. "Synthesis and Validation of a C5 '-Pseudouridinyl Radical Precursor." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1501602637102475.

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7

Basharat, Siama. "Precursor Synthesis and Chemical Vapour Deposition of Group 13 Oxides." Thesis, University College London (University of London), 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487670.

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This thesis is primarily concerned with the precursor synthesis and chemical vapour deposition of group 13 oxides. The gas sensing properties of some of the films prepared have also been investigated. Chapter 1 gives an introduction to techniques used for deposition, in particular chemical vapour deposition (CYD). Chapter 2 describes the synthesis of gallium and indium alkoxides incorporating donor functionalised ligands. The donor-functionalised alkoxides [R2M(OR,)h (M =Ga, R = Et; M = In, R = Me; R' = CH2CH2NMe2, CH(CH2NMe2h CH2CH20Me, CH(CH3)CH2NMe2, C(CH3hCH20Me) were synthesised by the 1 : I reaction of R3M with R'OH in toluene at room temperature. Gallium and indium bis-alkoxides [RM(OR')2] (M =Ga, R =Et; M =In, R =Me; R' = CH2CH2NMe2, CH(CH2NMe2)2, CH2CH20Me, CH(CH3)CH2NMe2, C(CH3hCH20Me) have also been synthesised by the I : 6 reaction of R3M with R'OH i.n toluene under reflux conditions. Homoleptic gallium trisalkoxides [Ga(ORhh have been prepared by the I : 6, reaction of [Ga(NMe2hh with R'OH. Decomposition of all the compounds have been studied by thermal gravimetric analysis in Chapter 3. The formation of thin-films of gallium oxide 'via single-source low pressure chemical vapour deposition (LPCYD) methodology was investigated including detailed film growth studies and characterisation. The compounds described above were used as precursors and deposition was achieved at 550°C. Chapter 3 also investigates the formation of thin-films of gallium and indium oxide using aerosol assisted chemical vapour deposition (AACYD). This involved the ill situ reaction of [Ga(NMe2hh or R3M with a donor functionalised alcohol (R'OH). Gas sensing experiments on selected Ga203 films deposited by AACVD are described in Chapter 4.
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8

Peters, Emily Sarah. "Precursor synthesis and chemical vapour deposition of transition metal sulfides." Thesis, University College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408505.

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9

Roberts, Glyn. "The influence of catalyst precursor chemistry on methanol synthesis activity." Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317194.

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10

Xu, Qing. "Intramolecular benzyne trapping in synthesis of a Vitamin E precursor." Thesis, Cardiff University, 2004. http://orca.cf.ac.uk/56008/.

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Intramolecular benzyne trapping by alcohols have been applied to the synthesis of a series of racemic chromans. The theme of this project was to utilise this technique in the synthesis of the precursor, (/)-8-iodo-6-methoxy-2,5,7-trimethyl chroman-2-methanol, to the natural product Vitamin E. The racemic form of the above compound has been synthesised in 12 linear steps from the commercially available 2,6-dimethyl-4-nitroanisole. Attempts to synthesize the enantiomerically enriched side chain (-)-(1S)-3,4-dihydroxy-3-methyl-1-butyne have also taken place and was achieved in seven linear steps. Methylation of 8-iodo-6-methoxy-2.5.7-trimethyl chroman-2-methanol on its 8 position was carried out by Stille coupling reaction the best result was a 25% conversion to the product. In addition, a series non-racemic chromans have also been synthesised. The benzyne precursors were prepared by condensation between the dianion 391 and allylic halides, and the chirality introduced by AD-mix reactions of the resulting alkenes.
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11

Harvey, G. "Multi-enzyme complexes of DNA precursor pathways in uninfected mammalian cells and cells infected by Herpes simplex virus type-1." Thesis, University of Aberdeen, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377617.

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This study was carried out to investigate the existence of a functioning multi-enzyme complex, providing DNA precursors, in a mammalian cell system. Both uninfected BHK-21/C13 cells and cells infected with HSV-1 were investigated. Sucrose gradient centrifugation of uninfected BHK cell lysates showed co-sedimentation of a number of DNA precursor pathway enzymes, indicative of a multi-enzyme complex, including DNA polymerase, thymidine kinase, NDP kinase, dihydrofolate reductase and ribonucleotide reductase. This complex association was seen to be cell-cycle dependent and sensitive to ionic conditions. The enzymes involved were not non-specifically bound to either RNA or DNA, but did have template DNA associated at times of DNA replication. Sedimentation analysis of virus-induced enzymes synthesised in HSV-1 infected cells showed the enzymes not to form such a complete complex, although thymidine kinase and ribonucleotide reductase did sediment together. Again, this association was sensitive to ionic conditions. Optimally permeabilized cell systems were characterised and implemented to carry out kinetic analysis. No evidence for substrate channeling, in either uninfected or HSV-1 infected BHK-21/C13 cells, was obtained using such permeabilized cell systems.
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12

Shah, Saral. "SOLUTION PROCESSIBLE AROMATIC POLYIMIDES VIA DIELS ALDER PRECURSOR." Master's thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3509.

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Aromatic polyimides are interesting materials since they possess outstanding key properties such as thermoxidative stability, high mechanical strength, high modulus, excellent electrical properties, and superior chemical resistance. However, their low solubility makes them difficult to characterize, process and obtain high molecular weight polymer. In this report, we synthesized a series of precursor polymers that contains Diels-Alder (DA) adducts of anthracene. Different dienophiles were tried. These precursor polymers are soluble in common organic solvents such as chloroform and can be easily processed to thin films. Heating the film above 215 degree induce retro-DA reaction, which generated the fully aromatic polyimides in situ. The solid-state retro-DA reactions were monitored by ATR-FTIR and UV-Vis spectra. The fully aromatic polyimides are highly stable and their thin films are insoluble in organic solvents. Profilometry and AFM studies showed that after the thermal treatment, the films are smooth and pin-hole free, while the volumes decreased with a percentage close to the weight loss caused by retro-DA reaction. These Polymers can have a wide range of potential applications from thermal patterning polymers to organic photovoltaics.
M.S.
Department of Chemistry
Sciences
Industrial Chemistry MS
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13

Dasgupta, Hridoydip Ranjan. "Studies on novel methodologies for the synthesis of precursor of bioactive compounds." Thesis, University of North Bengal, 2021. http://ir.nbu.ac.in/handle/123456789/4341.

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14

Säberg, Alexander. "Synthesis of a clickable FDG precursor for PET in vivo imaging." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-120586.

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The thesis of this study describes a synthesis way to produce an alkyne equipped clickable precursor of 2-deoxy-2-fluoro-D-glucose (FDG) with a beta-configuration. This FDG-derivate is produced with a clickable link in purpose to be used in PET in vivo imaging. The product was synthesized by acetylation protection and further epoxidation on the glucose analog D-Glucal. Glycosylation occurred by electrophilic reaction of propargyl alcohol and configuration of the product was ensured during Lattrell-Dax inversion.
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15

Vasconcelos, Leonardo de. "Síntese de um fragmento precursor do fármaco Indinavir." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-23042013-141617/.

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Neste trabalho foram aprofundados nossos estudos para obtenção da (S)-2-terc-butilamida-4-(3-picolil)piperazina, pela abertura da (S)-2-terc-butilcarboxamida-N-p-tosilaziridina seguida de ciclização, em 78% de rendimento, com o triflato de vinildifenilsulfônio. A aziridina foi preparada por um processo de ciclização, em condições de transferência de fase, partindo-se da L-serina, um aminoácido natural de baixo custo. Esta rota sintética rendeu um material que apresenta a mesma estereoquímica S do fragmento piperazínico usado na síntese do Indinavir, podendo vir a constituir uma via alternativa para a obtenção deste fármaco.
In this work we performed a deeper study for obtaining (S)-2-tert-butylamide-4-(3-picolyl)piperazine by opening (S)-2-tert-butylcarboxamide-N-p-tosylaziridine followed by cyclization, in 78% yield, with diphenylvinylsulfonium trifluoromethanesulfonate. The aziridine were prepared by a cyclization process in phase transfer conditions, starting from L-serine, a low cost amino acid. This synthetic route yielded a material which has the same S piperazinic fragment stereochemistry used in the synthesis of Indinavir, and may constitute an alternative route for obtaining this drug.
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16

Johnson, Harry Dale. "Synthesis, Characterization, Processing and Physical Behavior of Melt-Processible Acrylonitrile Co- and Terpolymers for Carbon Fibers: Effect of Synthetic Variables on Copolymer Synthesis." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/32373.

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A novel photocrosslinkable and melt processible terpolymer precursor for carbon fibers has been successfully synthesized and characterized. The terpolymer was synthesized by an efficient emulsion polymerization route and has a typical composition of acrylonitrile/ methyl acrylate/acryloyl benzophenone in the molar ratio of 85/14/1. This thesis describes a systematic variation of the polymerization variables in the emulsion polymerization which may further enhance the system. In particular, the effects of chain transfer agent, initiator, and surfactant concentration on the polymer properties were studied.
Master of Science
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17

Wang, Wei. "Computational and synthetic approaches to the synthesis of a potential high-temperature organic superconductor precursor: C₃₆ N₄." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3337538.

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Thesis (Ph.D.)--Indiana University, Dept. of Chemistry, 2008.
Title from PDF t.p. (viewed on Jul 27, 2009). Source: Dissertation Abstracts International, Volume: 69-11, Section: B, page: 6813. Adviser: Lawrence K. Montgomery.
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18

Soofivand, F., M. Salavati-Niasari, and F. Mohandes. "Synthesis and Characterization of Silver Choromate Nanostructures via a Simple Precipitation Method." Thesis, Сумський державний університет, 2012. http://essuir.sumdu.edu.ua/handle/123456789/34771.

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In summary, Ag2CrO4 nanostructures were prepared via a simple precipitation method by using [Ag(HSal)] as a new silver precursor. According to SEM images, the morphology of silver chromate nanostructures was 1-D and 3-D by using [Ag(HSal)] and AgNO3, respectively. Besides, SDS molecules were applied to decrease the particle size of the assynthesized products. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34771
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19

Kajla, Mayur Kumar. "Investigations on cellular nanoparticles required for synthesis of chitin the precursor for chitosan." Doctoral thesis, [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=979027810.

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20

Edery, Isaac. "Role of cap function during eukaryotic protein synthesis and precursor messenger RNA splicing." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75970.

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The cap structure, m$ sp7$GpppX (where X = any nucleotide), is present at the 5$ sp prime$ end of all eukaryotic cellular messenger RNAs (except organellar). Previous studies have demonstrated that during protein synthesis the cap structure is recognized by a $ sim$24 kDa cap binding protein (CBP), termed eukaryotic initiation factor 4E (eIF-4E). With the use of a newly developed cap-analogy affinity matrix a high molecular weight complex that contains eIF-4E was purified, termed eIF-4F. In addition to eIF-4E this CBP complex consists of eIF-4A and a 220 kDa polypeptide (p220). Using an RNA unwinding assay direct evidence was obtained indicating that eIF-4F, eIF-4A and eIF-4B functionally interrelate resulting in helicase activity. Secondary structure in the 5$ sp prime$ untranslated region of eukaryotic mRNAs inhibits translation, therefore this unwinding activity is most likely required for efficient 40S ribosomal subunit attachment to mRNA. To fascilitate the purification and biophysical characterization of eIF-4E, the yeast homolog was overexpressed in E. coli. mRNA secondary structure can also inhibit translation in trans by another mechanism. This was shown for the unique structure (TAR) at the 5$ sp prime$ end of all mRNAs from the human immunodeficiency virus-1 (HIV-1). The mechanism of translation inhibition involves the activation of the double-stranded RNA dependent kinase (dsI), which catalyzes the phosphorylation of eIF-2. This is the first demonstration of a specific naturally occurring mRNA sequence that can activate dsI. A novel translational regulatory mechanism is proposed. Finally, the cap structure is also required for efficient precursor mRNA splicing in HeLa nuclear extracts. These and other studies indicate that the cap structure plays a multifunctional role during regulation of gene expression.
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21

McMillan, Stephen Murray. "Synthesis of silicon carbide ceramics at low temperatures by an organometallic precursor rate." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240667.

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22

Trofymchuk, I. M., and L. A. Belyakova. "Sol-gel Synthesis of β-Cyclodextrin-containing Silicas with 3-(chloropropyl)triethoxysilane as Precursor." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35233.

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The sol-gel synthesis of β-cyclodextrin-containing silica materials is reported. Organosilicas were pre-pared in tetraethylorthosilicate–3-(chloropropyl)triethoxysilane–β-cyclodextrin–ethanol–water system. These materials were characterized by IR spectroscopy and thermogravimetric analysis. Porosity of orga-nosilicas was characterized on nitrogen adsorption/desorption isotherms. The porosity analysis demon-strates that cyclodextrin-silica based materials are an isotherm Type I substance. The surface areas of the organosilicas with incorporated β-cyclodextrin are in the range 430–580 m2 g1; materials containing up to 0.005 mmol g1of β-cyclodextrin moieties have been successfully prepared. Synthesized organosilicas are stable in aqueous medium and could be used in processes of pollutants removal. The present study demon-strates a simple time-saving method of cyclodextrin-containing silicas obtaining via one-pot synthesis in mild condition without using toxic solvents, costly templates or cyclodextrin derivatives. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35233
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23

Seo, Michael. "Plasma-assisted nanofabrication of vertical graphene- and silicon-based nanomaterials and their applications." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/12285.

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Scarcity of physical resources, increasing concerns for safety and hazardous waste disposal which affects the environment drove the current nanoscience research to focus on developing low-cost, green and environmentally friendly method of obtaining nanomaterials. Yet, developing such smart and innovative processes is at premature stage. Over a few decades, many nanomaterials have been found and investigated. Amongst many nanomaterials, carbon and silicon nanomaterials attracted immense attention due to their abundance, low cost, unique and tunable properties which are promising for many applications. However, making nanostructure with uniformity and desirable properties is often difficult due to a lack of precise control which inherits from fabrication process. Furthermore, many techniques cannot satisfy green and environmentally friendly synthesis of mentioned nanomaterials. Therefore, efficient, effective and environmentally friendly way to create mentioned nanostructures with tunable properties remains a major challenge. Over a few decades, many investigations demonstrated that plasma technique can create uniform nanostructure in an environmentally friendly way which holds great promise as a versatile nanofabrication tool. Therefore, in this thesis, I investigate the plasma aided fabrication of Nobel Prize winning graphene related material called vertical graphenes will be discussed in details. Vertical graphene features are expected to be promising for a host of applications, from energy storage devices to gas detection. Therefore, I will explore the potential of vertical graphenes in diverse applications. Furthermore, green way of creating vertical graphenes using natural precursors from different states of matter will also be investigated. Following on from investigation of vertical graphenes, I will also demonstrate controllable, green synthesis of silicon based nanostructures without hazardous silicon precursor material using plasma-assisted methods.
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24

Ozerciyes, Berker. "A Novel Precursor For Synthesis Of Zirconium Tungstate And Preliminary Studies For Nanofiber Production." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610383/index.pdf.

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Zirconium tungstate (ZrW2O8) is a ceramic that shows large isotropic negative thermal expansion over a wide range of temperature. This unique property makes it an interesting candidate for applications where thermal expansion mismatch between components constitutes a problem. ZrW2O8 is typically produced by solid-state reaction between zirconium oxide and tungsten oxide at 1200oC. In some studies, ZrW2O8 precursors have been produced from relatively expensive zirconium and tungsten sources. While the origin of negative thermal expansion has been the main focus in the majority of publications, production of particles with controlled size, distribution and morphology has not been studied extensively. Electrospinning is a simple technique for producing micron/nano sized fibers from polymer solutions. The method can also be used for producing ceramic or polymer/ceramic composite fibers by electrospinning of a mixture of ceramic precursors or ceramic nanoparticles with suitable polymers. Ceramic precursors could be synthesized either by sol-gel or chemical precipitation routes before mixing them with polymer solutions and a final burnout step would be needed, in case the fiber is desired to be composed of the ceramic phase. Electrospinning technique has not been employed to the production of ZrW2O8 ceramic fibers. In this study a novel precursor for ZrW2O8 from relatively cheaper and abundant starting chemicals, namely zirconium acetate and tungstic acid were used. Experimental details of development of the precursor are presented with a discussion on the effects of solution parameters on the phase purity of the fired product. Besides the solution parameters investigated (i.e. solubility of tungstic acid, adjustment of the stoichiometry, final pH of the solution, ageing time), evolution of the heat treatment protocol was used in the production of phase pure ZrW2O8. Second, the suitability of the developed precursor for producing ZrW2O8 in fiber form was investigated. Preliminary studies involved the adjustment of the viscosity of precursor solution for electrospinning with poly (vinyl alcohol) (PVA). Optimum PVA concentration leading to bead-free nanofiber mats and a method to increase the fiber production rate were reported. The characterization of the products was achieved by SEM and XRD.
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25

Dill, Kathryn Ann. "Process Optimization for the Synthesis of Gold Nanoparticles from a Mixed Metal Precursor Solution." VCU Scholars Compass, 2018. https://scholarscompass.vcu.edu/etd/5326.

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Separation methods involving a mixture of metals typically include upfront processing that leads to one final product. To lower the waste and ultimately environmental burden, the potential to synthesize multiple functional products from a mixed metal precursor solution is explored. The initial precursor solutions contained varying ratios of gold and copper, gold and nickel, and finally a ternary solution of gold, copper, and nickel. The amount of gold was kept constant, while the amount of copper and/or nickel was sequentially increased. Two separate synthesis processes were tested, the traditional Turkevich method involving trisodium citrate and another chemical reduction method involving sodium borohydride. The particle size and chemical composition of the synthesized particles were characterized using TEM, DLS and ICP-OES. It was determined that gold nanoparticles still formed at a ratio of 1 to 2 gold to copper while using trisodium citrate or sodium borohydride as the reducing agent. The same limiting ratio was observed for the gold to nickel reactions in the presence of either trisodium citrate or sodium borohydride. The ternary mixture limit for gold nanoparticle formation was a molar ratio of 1 to 1 to 1 gold to copper to nickel. The repeatability and stability results for the optimized binary reaction conditions indicate that using sodium borohydride as the reducing agent consistently produces more stable particle suspensions. Quantifying the environmental impact using green chemistry metrics indicate the Turkevich reactions for the optimized reactions have the lower environmental factors.
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Krishna, Prasad Golla. "Synthesis of multicyclic 2-pyridones from a formyl and chlorometylene substituted precursor using a strategy of directed diversity-oriented synthesis." Thesis, Umeå universitet, Kemiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-56763.

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Multi ring-fused 2-pyridones have shown interesting activity in a variety of biological systems. It would be of great interest to explore the biological application of even more multi heterocyclic ring fused 2-pyridones. ‘Diversity oriented synthesis’ is an excellent concept emerged in recent years to access compounds with structurally and stereochemically diverse skeletons. This served as an efficient avenue for synthesizing various ring fused 2-pyridones using formyl, chloromethylene substituted 2-pyridone ( 6) as a starting compound. By treating the starting material (6) with various nucleopliles, different sized heterocyclic ring fused 2-pyridones has been synthesized. Additionally, an improved methodology for the synthesis of naphthyridones was presented.
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Choujaa, Hamid. "Synthesis of novel single-source precursors for CVD of mixed-metal tungsten oxide." Thesis, University of Bath, 2008. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.478944.

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There is a considerable interest in the use of tungsten oxide in the research and development of new materials and devices, such as gas sensors and as photocatalysts. In order to improve the photocatalytic properties of WO3, its combination with metals which allows the preparation of WMxOy materials are believed to be promising photocatalysts under visible light. The present work deals with the synthesis of homo- and hetero-metallic tungsten alkoxide and amide compounds using the single source precursor approach for potential chemical vapour deposition precursors of mixed-metal oxide films.
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Wattanasereekul, Saengchai. "A new synthetic pathway to 8-hydroxy-2,4,6-trimethyl-4-nonenoic acid as precursor for the total synthesis of jasplakinolide." [S.l. : s.n.], 2005. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB12168199.

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29

Akhtar, Y. "Studies on the maturation pathway of ribosomal precursor RNA : Analysis of Xenopus ribosomal RNA synthesised by transcription in vitro." Thesis, University of Liverpool, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382054.

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30

Bera, A. "Scalable Synthesis of dispersible semiconducting metal chalcogenides nanocrystals and their application." Thesis(Ph.D.), CSIR-NCL, 2021. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/6030.

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Abhijit Bera_Ph.D thesis
The work incorporated in this thesis is mainly focused on various single source metal precursors like metal thiolates and metal dithiocarbamate complexes. Herein, several simple and general methods have been developed for the synthesis of various such single source metal precursors, which comprising the main two constituents of metal chalcogenide nanocrystals (NCs), namely, the tiny inorganic metal chalcogenide complex as core and an organic molecule as shell. Specially, both binary metal thiolates and bimetallic (ternary) thiolates have been prepared and both of them turned out to be excellent precursors for the synthesis of metal sulfide/selenide NCs. The methods used to prepare metal chalcogenide NCs included a direct-heating (solvo-thermal decomposition) method or solid state grinding method. First, the large scale synthesis of various 2D molecular precursors like metal thiolates and metal dithiocarbamate complexes (M-C8DTCA) have been developed and studied their thermal decomposition to metal sulfide NCs via solution based methods. We observed that some of the metal thiolates like Pb-thiolate requires very high temperature to decompose into PbS resulting in particles bigger than their Bohr exciton radius and hence displayed poor optical properties. In the next, to reduce the decomposition temperature an active sulfur precursor called octyl ammonium octyldithiocarbamate (C8DTCA) has been utilized for the synthesis of various metal sulfide NCs (including most challenging PbS NCs, with tunable optical properties) by solution based method (hot injection) or solid state grinding method. We also show that the size of the nanocrystals could be controlled by changing the reaction temperature or metal: chalcogenide precursor ratio. Interestingly, we have also been successful in establishing that these newly developed solid state grinding methods are scalable without compromising their structural and optical properties. The binary or ternary materials synthesized by these solid state routes could be re-dispersed as desired in non-polar organic solvents allowing them to be solution processible. The optical properties of the metal chalcogenide nanocrystals could further be improved by post synthetic surface passivation.
CSIR-NCL
AcSIR
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31

Behof, William James. "Progress Towards the Synthesis of Novel Graphite Derivatives from a Solution Processable Poly-Cyano Precursor Polymer." NCSU, 2010. http://www.lib.ncsu.edu/theses/available/etd-12212009-134714/.

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In this thesis the synthetic progress towards the development of a novel potentially conducting ladder polymer, through the direct writing of a soluble precursor polymer, is presented. The proposed ladder polymer can be synthesized through three steps; the synthesis of a poly-cyano monomer for polymerization, the synthesis of a poly-cyano precursor polymer, and a one step cascading cyclization of a poly-cyano polymer. First addressed is the rather specific palladium catalyzed coupling conditions needed for a single C-C bond forming reaction of highly electron deficient aryl cyanides. The optimization of this coupling reaction, as performed on small oligomers, illustrates that the choice of metal catalyst, supporting ligand, and most especially base have a large influence on the yield. Secondly, a new, highly selective synthetic route to a desired monomer is presented. Third, the precursor polymer is synthesized through the application of the aforementioned optimal conditions. It is observed, through an optimization study, that the highest yielding test couplings do not yield the highest molecular weight polymer. Finally, three cyclization routes, of which only one is a cascading cyclization, are discussed. Photo-physical properties of the isolated fused ring systems show that the larger fused ring oligomers have modest bandgaps and are potential candidates as semi-conducting materials.
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32

Hagadorn, Susannah Marie. "I. Synthesis of mycarose from an acyclic precursor ; II. studies toward the sysnthesis of Roridin E." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14961.

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33

Tan, Kam Ho. "Synthesis and electrical properties of copolymers and blends of polyacetylene via poly(phenyl vinyl sulfoxide) precursor." HKBU Institutional Repository, 1992. http://repository.hkbu.edu.hk/etd_ra/16.

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34

Leone, S. "3-Heteroalkyloxindole : an interesting precursor for the synthesis of polycondensed heterocyclic systems with potential biological activity." Doctoral thesis, Università degli Studi di Milano, 2006. http://hdl.handle.net/2434/153961.

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Considering the general interest on the indole nucleus as well as of its derivatives such as indolin-2-one, which is inserted in a large number of alkaloids and in some pharmacological active compounds, the researches were focused on the synthesis of different classes of indole compounds of potential biological interest. First, a very efficient protocol for the preparation of ethyl 4,2'-dioxaspiro[cyclohexane-1,3'-indoline] nucleus 23 was planned, which is a very versatile synthon. Starting from 23, the spiro[perhydroazepine-5,3'-indoline] nucleus 24 functionalized in both positions 2 of the azepine and 2' of the indoline ring with an oxo group was obtained. Azepino-indole system is present in several alkaloids, such as Gelsominum, in particular gelsemoxomine, as well as in more simple compounds characterized by insecticide activity such as spiro[perhydro-azepine-4,3'-indoline] functionalized at nitrogen atoms with proper substituents. Starting from the key intermediate 24, several synthetic targets were achieved such as: i) the regioselective reductions of its carbonyl functions aiming to obtain the 2'-oxospiro[perhydro-azepine-4,3'-indoline] 26, the 4-oxospiro[perhydro-azepine-4,3'-indoline] derivative 27 and the complete reduced spiro[perhydro-azepine-4,3'-indoline] nucleus 28. ii) the preparation of alkaloids containing tetrahydropyrroleindole nucleus 29 functionalized with a chain in position 3a, which, as I reported above, is the biological scaffold present into alkaloids of the Calabar bean and of the genus Pseudophryne and Flustramine. iii) the preparation of the hexahydropyraneindole nucleus 30, functionalized with a chain in position 4a of the ring. Studies on the preparation of the above compounds in enantiopure form were also performed. The best result was found performing an asymmetric synthesis of azepinoindole nucleus 24 by the way of an asymmetric Schmidt reaction. In the retrosynthetic scheme it is shown the preparation of the enantiopure compounds 24' starting from 23 via azepine compound 31. Finally, starting from 4,2'-dioxaspiro[cyclohexane-1,3'-indoline] 23, the lactone 32 was synthetized. Compound 32 is the key intermediate for the preparation of tetrahydrofuraneindole 33, another important nucleus present in the Physovenine, one of the alkaloids of the Calabar bean.
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35

Xu, Zhen. "On-surface synthesis of two-dimensional graphene nanoribbon networks." Kyoto University, 2020. http://hdl.handle.net/2433/254529.

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36

Stevenson, David. "An investigation of potential multi-enzyme complexes of DNA precursor synthesis and DNA replication in eukaryotic cells." Thesis, University of Aberdeen, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277287.

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1. Efforts to display a 'replitase' complex in two disparate lower eukaryotes, Saccharomyces cerevisiae and Physarum polycephalum whether employing physical or kinetic techniques have yielded no evidence to support its existence at this level of biological complexity. 2. Some indication of potential interaction of the folate-metabolising enzymes, dihydrofolate reductase and thymidylate synthase, were attained from affinity chromatography and non-denaturing gel electrophoresis studies of S. cerevisiae lysates. 3. Experiments on lysates prepared from S. cerevisiae spheroplasts imply a cytoplasmic location for the enzymes NDP kinase, dihydrofolate reductase, thymidylate kinase and thymidylate synthase while DNA polymerase, by virtue of its much reduced activity in such extracts, appears to be non-cytoplasmic. 4. Lysates of S-phase P. polycephalum macroplasmodia and exponentially-growing microplasmodia have different DNA polymerase elution profiles when subjected to Sepharose 6B gel filtration chromatography implying the existence of an S-phase-specific activity. 5. Fractions from the trailing section of the S-phase-specific peak of P. polycephalum DNA polymerase following gel filtration chromatography are capable of utilising [3H]dTMP but not [3H]TdR as substrate. The substrates of dTMP synthetase (dUMP plus co-factors) are not capable of substituting for dTTP in the DNA polymerase assay in these fractions. 6. Thymidylate synthase does not seem to be physically linked with the DNA polymerase from S-phase BHK-21/C13 cells.
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37

Love, Christopher J. "The carbometallation of allylic alcohols : scope stereochemistry, and a synthesis of a precursor to Tsukubaenolide (FK 506)." Thesis, University of Southampton, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303109.

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38

Dong, Bin. "Controllable synthesis for fabrication of micro/nano-structured mesoporous precursor particles for high performance lithium-ion batteries." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/52091/.

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Increasingly global warming and air pollution caused by the consumption of fossil fuel have imposed the priority of using green energy. As a result, the use of rechargeable lithium-ion batteries (LIBs) has increased rapidly Olivine-structured LiFePO4 is considered as one of the most promising positive electrode materials owing to its significant advantages of nontoxicity, low cost of raw materials, good structural stability at high temperature, excellent safety performance, and relatively high theoretical specific capacity (170 mAhg-1) with a flat discharge-charge potential (3.45V vs. Li+/Li). Therefore, LiFePO4 battery becomes a reliable material for energy storage system used in hybrid electric vehicles (HEVs), full electric vehicles (EVs), plug-in hybrid electric vehicles (PHEVs), and portable devices. However, the poor rate performance of LiFePO4, resulting from its intrinsic low Li+ diffusivity (10-17 to 10-14 cm2s-1) and low electronic conductivity (10-9 to 10-8 S cm-1), has become a technical bottleneck to confine its widely practical applications. Following previous studies, a systematic study on controllable preparation of LiFePO4 positive electrode material with nanoscale size, or hierarchical micro/nano mesoporous structure has been carried out using various synthesis methods, including impinging stream reaction (ISR), ultrasonic-intensified impinging stream reaction (UISR), two-step co-precipitation method, and two-step hydrothermal method (UIHT). The physical and chemical properties of as-synthesized products are measured by XRD, FTIR, SEM, TEM, BET, Mastersizer, CV, and charge-discharge test. Based on these observations, the relationship among particle morphology, electrochemical performance, and impacts of fluid dynamics is evaluated in this work.
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39

Tang, Mingnam. "Synthesis of 2H-1-Benzthiocin: a Precursor for the Generation of the "4n+2" Pi-electron 1-Benzthiocinide Anion." [Johnson City, Tenn. : East Tennessee State University], 2001. http://etd-submit.etsu.edu/etd/theses/available/etd-0828101-115953/restricted/tangm112701b.pdf.

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40

Mei, Mawonga N. "A model route to a brominated hydroxy[2,3-c]pyran- a potential precursor to extended quinones." Thesis, Cape Peninsula University of Technology, 2008. http://hdl.handle.net/20.500.11838/749.

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A thesis submitted in fulfilment of the requirements for the degree Magister Technologiae (Chemistry) in the Faculty of Applied Sciences, Department of Chemistry, Cape Peninsula University of Technology, 2008
Green et al. attempted to synthesize linear naphthopyranquinones from a naphthyl dioxolane using a TiCl4 as a catalyst. They managed to synthesise an angular naphthopyran as well as a linear naphthopyran in low yield. They showed that reducing the steric strain at position 1 of the naphthyl dioxolane afforded a low percentage yield of the linear naphthopyran plus an angular one. This thesis describes the synthesis of linear naphthopyrans with an improved percentage yield using TiCl4 as a catalyst. This was achieved by placing a OMe group of less steric hinderance at position 1 and a Br atom at position 4 of a naphthyl dioxolane. The OMe group at position 1 was to allow isomerisation to occur at position 2, and the Br atom was to inhibit isomerisation at position 4, thereby inhibiting the formation of the angular naphthopyran.
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41

de, Jongh Leigh-Anne. "The molecular precursor approach to control the morphology of Co₃O₄ on support materials." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2539.

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In this project, the TMP method was employed to produce “active sites.” These active sites are for influencing and controlling the Co₃O₄ growth. One of the aims was to investigate what effect the grafting of the molecular precursor has on the nature and distribution of active sites on the various support materials. The second aim was to investigate the effect an increase in molecular precursor loading, in various impregnation steps, has on the nature and distribution of the active sites. The third aim was to investigate the effect of the steric constraints of ligand groups, by changing the molecular precursor, on the nature and distribution of active sites. The fourth aim was to use the different aspects discussed above and apply them to investigate what effect the above-mentioned modifications have on Co₃O₄ morphology. While another aim was to investigated what effect varying the quantity of Co(NO₃)₂•6H₂O has on Co₃O₄ morphology. Lastly, we investigated what effect varying the impregnation procedure and calcination temperature have on the Co₃O₄ morphology. The effect the support has on the phase of titanium molecular precursor was investigated using molecular precursor, ⁱPrOTi[OSi(O[superscript(t)]Bu₃)]₃. The supports used were Silica 922, NanoDur, Aerosil 200, Stöber spherical silica, SBA-15, mod MCM-41 and sMCM-41. The molecular precursor ⁱPrOTi[OSi(O[superscript(t)]Bu₃)]₃ was revealed to be in the orthorhombic TiO₂ with space group P(cab), normal brookite lattice, on Silica 922 after calcination but only an isolated area displaying this morphology. Generally we do not observe any TiO₂ on the support, which indicates that we have produce site-isolated sites, suggesting the TMP method has been successful on all of the various supports. The emphasis is placed on the effect of this molecular precursor and the respective support has on the Co₃O₄ morphology in Chapter 3. In this Chapter, a unique morphology was observed on Silica 922 which showed Co₃O₄ nanorods of cubic Co₃O₄ in the space group Fd-3m. Silica 922 was used for the remainder of the thesis to investigate the effect the quantity of molecular precursor has on the nature of active sites and Co₃O₄ morphology in Chapter 4. This support was also used to investigate the effect the amount of Co(NO₃)₂•6H₂O has on Co₃O₄ morphology in Chapter 5. This support was lastly used to investigate the steric constraints of the ligand groups, Ti[OSi(O[superscript(t)]Bu)₃]₄ (TiSi4), ⁱPrOTi[OSi(O[superscript(t)]Bu)₃]₃ (TiSi3), (OtBu)₃TiOSi(O[superscript(t)]Bu)₃ (TiSi) and the least sterically constrained Ti(OⁱPr)₄ has on the loading of precursor and Co₃O₄ morphology in Chapter 6.
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42

Tietze, Remo, Rene Panzer, Thorben Starzynski, Chris Guhrenz, Florian Frenzel, Christian Würth, Ute Resch-Genger, Jan J. Weigand, and Alexander Eychmüller. "Synthesis of NIR-emitting InAs-based core/shell quantum dots with the use of tripyrazolylarsane as arsenic precursor." Wiley-VCH Verlag GmbH & Co. KGaA, 2018. https://tud.qucosa.de/id/qucosa%3A33887.

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Tris(3,5-dimethylpyrazolyl)arsane (1) is introduced as an low-cost and convenient to handle arsenic precursor for the straight forward synthesis of InAs quantum dots (QDs). Transamination of 1 with the solvent oleylamine (OLAH) gives trioleylarsane (As(OLA)3) which in the presence of the reducing agents DIBAL-H or P(OLA)3 yields InAs QDs via a typical hot injection approach. The size of the obtained InAs core QDs are tuned by varying the reaction time, the amount of the applied reducing agent, or even more effectively by changing the indium and/or zinc halide precursors, InX3 and ZnX2 (Cl, Br, or I). Passivation of the resulting InAs particles with a protective ZnS or ZnSe shell results in improved photoluminescence (PL) of the core/shell QDs covering a spectral range between 600–1150 nm.
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43

Kennedy, Steven Roger 1971. "Synthesis, characterization and use of peroxotungstic ethoxide as a precursor to wet-chemically derived tungsten oxide thin films." Thesis, The University of Arizona, 1996. http://hdl.handle.net/10150/278554.

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In this work a new wet-chemical method of preparing tungsten oxide thin films is described. This involves the dissolution of tungsten metal in aqueous hydrogen peroxide and reaction with acetic acid to form an alcohol-soluble precursor. All synthesis stages of this new precursor, termed peroxotungstic ethoxide, are characterized to determine possible reactions. The chemical and microstructural evolution of films is described as a function of firing temperature, utilizing infrared spectroscopy, diffraction and other optical data. A novel method of increasing the crack-free thickness of the films is given: a combination of oxalic acid dihydrate as a solution additive and film firing under controlled humidity. With this combination, fired crack-free films up to one micron in thickness were prepared. Oxalic acid dihydrate roughened and also caused crystallization of these films at lower temperatures (250°C) than expected. These rougher films exhibited an improved electrochromic response, as measured by optical and electrochemical characterizations.
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44

Abdelhady, Ahmed Mohammed Said lutfi. "Developing novel processes in chemistry for several types of nanoparticles." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/developing-novel-processes-in-chemistry-for-several-types-of-nanoparticles(0712d3c6-e2d5-415a-b787-c9ce457e1355).html.

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The work presented in this thesis reports the use of a series of novel thiobiuret metal complexes [M(SON(CNiPr2)2)n] (M = Cu, Ni, Fe, Zn, Cd or In; n = 2 or 3) for the first time as single source precursors for the colloidal synthesis of metal sulfide nanoparticles. Other single source precursor(s) were also used for the synthesis of CdSe, CdS, CdSe/CdS core/shell, CdSeS alloys and Cu2-xS nanoparticles in microfluidic reactors. Thermolysis experiments of [Cu(SON(CNiPr2)2)2] using only oleylamine produced Cu7S4 nanoparticles as a mixture of monoclinic and orthorhombic phases. Pure orthorhombic Cu7S4 nanoparticles were obtained when a solution of precursor in octadecene was injected into hot oleylamine whereas, Cu1.94S nanoparticles were obtained when a solution of the precursor in oleylamine was injected into hot dodecanethiol. The thermolysis of [Ni(SON(CNiPr2)2)2] gave Ni3S4 in all cases except when precursor solution in oleylamine was injected into hot octadecene which produced NiS nanoparticles. The thermolysis of [Fe(SON(CNiPr2)2)3] in oleylamine/oleylamine produced Fe7S8 nanoparticles but other combinations, in most cases, gave amorphous material. Thermolysis of [Zn(SON(CNiPr2)2)2] in oleylamine produced spherical ZnS nanoparticles. Particles with size smaller than 4.3 nm had a cubic phase, whereas the particles with size larger than 4.3 nm had a hexagonal crystal structure as suggested by the selected area electron diffraction. Powder X-Ray diffraction showed that the CdS nanoparticles obtained from the thermolysis of [Cd(SON(CNiPr2)2)2] in oleylamine were cubic under all reaction conditions except when dodecanethiol was used as an injection solvent which produced hexagonal CdS. β-In2S3 were synthesized from the thermolysis of [In(SON(CNiPr2)2)3]. Transmission electron microscopy showed that the copper, nickel and iron sulfide nanoparticles had various morphologies such as spherical, hexagonal disks, trigonal disks, rods or wires; depending on the reaction temperature, concentration of the precursor, the growth time and the solvent/capping agent combination. The zinc and cadmium sulfide nanoparticles were mostly spherical whereas the indium sulfide nanoparticles were produced in the form of ultra-thin (< 1.0 nm) nanorods or nanowires. ZnxCd1-xS and CuInS2 nanoparticles were synthesised from the 1,1,5,5-tetra-iso-propyl-4-thiobiureto complexes of Zn, Cd and Cu, In, respectively. Powder X-Ray diffraction showed that the obtained ZnxCd1-xS nanoparticles are cubic under all reaction conditions. The ZnxCd1-xS nanoparticles had an average diameter between 3.5 to 6.4 nm as shown by transmission electron microscopy. The optical properties of the ZnxCd1-xS nanoparticles were highly dependent on the ZnS to CdS precursor ratio and the solvents/capping agents. Chalcopyrite (tetragonal), wurtzite (hexagonal) or a mixture of both CuInS2 nanoparticles were obtained depending on the reaction conditions. TEM showed that the CuInS2 nanoparticles could be synthesised with different morphologies (spherical, hexagonal, trigonal or cone). Luminescent CuInS2 nanoparticles were obtained only in the absence of oleylamine. [Cd(S2CNMenHex)2], [Cd(Se2P(iPr)2)2] and [Cu(SON(CNiPr2)2)2] were used as single source precursor(s) for the synthesis of CdS, CdSe, CdSe/CdS core/shell, CdSeS alloys and Cu2-xS in microfludic reactor. The CdS nanoparticles were in size range of 5.0 to 8.0 nm whereas the CdSe nanoparticles were ultra small (ca. 2 nm) with blue luminescence. The CdSe/CdS core/shell and the CdSeS alloys were bluish green or green luminescent depending on their size. The copper sulfide nanoparticles were found to be monoclinic Cu7S4 or monoclinic Cu7S4 with minor impurities of rhombohedral Cu9S5 depending on the reaction conditions.
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45

Zhu, Chaoyong. "Deoxyribonucleoside kinases in nuclear and mitochondrial DNA precursor synthesis : phosphorylation of anti-cancer nucleoside analogs in different subcellular compartments /." Stockholm, 2000. http://diss.kib.ki.se/2000/91-628-4367-2/.

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46

Jie, Yuanping Livant Peter D. "Tris(1,3-dihydroxy-2-propyl)amine, a planar trialkylamine synthesis, structure, and properties ; a potential precursor to hypervalent nitrogen /." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Spring/doctoral/JIE_YUANPING_0.pdf.

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47

Chen, Chi-Shian, and 陳錡賢. "Synthesis of Prussian Blue Analogue Precursor Complexes." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/39368449423897647069.

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碩士
高雄醫學大學
醫藥暨應用化學系碩士班
93
Most of cyanometalate-based cages is inspired by Prussian Blue FeII bridge FeIII with CN ligand. Those Prussian Blue analogue complexes which have been discussed as catalysts, sensors, molecular magnets, and sieves. Our effort focus on the synthesis of Prussian blue analogue complexes frameworks by using 3,5-dmTPM as spectator ligand in FeII and FeIII metal. The complex [(3,5-MeTPM)2FeII2(��-Cl3)][3,5-MeTPMFeIICl3] (1) was prepared from the reaction of FeCl2 and 3,5-MeTPM in a 1:1 ratio. The salts compound 1 was characterized by 1H NMR spectroscopies, and cyclic voltammetry. Treatment of 1 with excess CN- afforded [(3,5-MeTPM)FeII(CN)3)]- was characterized by NMR, infrared, and cyclic voltammetry. The reaction of 3,5-MeTPM with FeCl3 afforded complex [3,5-MeTPMFeIIICl3] (4) which was proved by element analysis, and cyclic voltammetry. The reaction of 4 with 3equiv. of AgCOOCF3 afforded [(3,5-MeTPM)FeIII(COOCF3)3](6) was characterized by X-ray diffraction and element analysis. Oxygenation of complex [(3,5-MeTPM)FeII(CN)3)]- by I2 afforded [(3,5-MeTPM)FeIII(CN)3)] which was characterized by infrared. The complex 6 was a novel structural mode which for an active site of Fe-Containing SOD (Superoxide Dismutase) enzyme.
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48

Chen, Jui-Wen, and 陳瑞文. "Synthesis of Morusin and Precursor of Acrovestone." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/71512237409847837528.

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碩士
國立彰化師範大學
化學系
93
Natural product, Morusin was isolated from the root bark of mulberry tree (a variety of Morus alba L.). It had important biological activities including anti- inflammation, potent inhibition of human PLC/PRF/5, T24, KB, OVCAR-3, H441 and HT-29 cells. According to important biological activities and the methods to synthesize Glychalcone and Glyflavone in our laboratory, we worked hard to want to synthesize it. Therefore, we synthesized chromen 6 via six steps from 1,3,5-trihydroxybenzene, including annelation, methylation, Clemmensen reduction, acylation, Fries rearrangement and dehydrogenation. On the other segment, we synthesized acid chloride 11 via five steps from 2,4-dihydroxybenzoic acid, including esterification, protecting PMB and methyl group, hydrolysis and then reacted with oxalyl chloride. With precursors 6 and 11 in hand, the synthesis of prenyldiketone 14 via two steps including addtion-elimination and alkylation. The formation of dimethylmorusin 15 via cyclization, dehydration and cleavage of PMB group in acidic condition. Finally, demethylation with EtSLi we prepared to expect to afford natural product, Morusin. Natural product, Acrovestone was isolated from plant (Acronychia pedunculata) and it had potent cytotoxicity(100% inhibition at 0.5 ug/ml) in the KB tissue culture assay. It also showed significant cytotoxicity against A-549, P-388, and L-1210 cells with ED50 values of 0.98, 3.28, and 2.95 ug/ml, respectively. According to important biological activities and the methods we had studied, we worked hard to want to synthesize it. Now, we had synthesized dibromochromene 23 by bromination of chromen 6, and precursor, bromoacetophenone 20 from 1,3,5-trihydroxybenzene via three steps including methylation, Friedel-Crafts acylation and bromination. Furthermore, we studied prenylation of chromen 6 to synthesize Acronyculatins E 22. Finally, we expected to synthesize natural product, Acrovestone by studying the reaction including palladium-catalyzed coupling, debromination, ring opening, asymmetric reduction and prenylation in the future.
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49

Kuo-Hsin, Sun, and 孫國欣. "Synthesis of Morusin Drivatives and Precursor of Theaflavins." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/65362874245812797787.

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碩士
國立彰化師範大學
化學系
92
Morusin was isolated from Moraceae plants, and it was a natural product and had biological activity. We had synthesized two precursors of Morusin, 5,2’-dimethoxy-4’-(4-methyl-benzyloxy) morusin 24 and 5,2’- dimethoxy morusin 64. In the research of deprotection, methyl, 4-methyl-benzyl and 4-methoxy–benzyl (PMB), were protecting groups that we wanted to deprotect. The total synthesis of Morusin was our purpose. Theaflavins were synthesized from Catechins during oxidative process. Theaflavins were included in black tea usually, and had much biological activity. The center structure of Theaflavins is a seven-members ring, and that was our initial purpose. We wanted to synthesize (6E,8E)-1,8-dibromo- 3,4,6-trihydroxy-5H-benzo[7]annulen-5-one 52 by 4-bromo-catechol 31 and 5-bromo- pyrogallol 41 ,then made a coupling reaction to get Theaflavins.
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50

Sahoo, Satya Prakash. "Synthesis of Lithium Orthosilicate by Polymer Precursor Route." Thesis, 2015. http://ethesis.nitrkl.ac.in/7874/1/2015_SYNTHESIS_SAHOO.pdf.

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My objective in this project is to synthesize phase pure lithium orthosilicate by using a novel polymer precursor route and simultaneously compare the results with lithium orthosilicate prepared by conventional solid state method. Source of silica is very important for the formation of lithium orthosilicate. For our work, the objective can be broadly highlighted as follows: 1. To study the effect of different sources of silica on the phase formation behaviour of lithium orthosilicate. 2. To compare the properties (thermal and microstructural) of lithium orthosilicate derived from polymer route and conventional solid state route. 3. To study the densification behaviour of polymer derived lithium orthosilicate and solid state synthesized lithium orthosilicate. 4. To study the effect of non-stoichiometric amount of silica on lithium sublimation.
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