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1
Jin, Pei-Wen. "Synthesis and Structure of Polynitro- and Polymenthylpolycyclic "Cage" Monomers and Polymers." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc332109/.
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The objective of this study was to synthesize and characterize new energetic polycyclic "cage" compounds.
As part of a program involved in the synthesis of new polynitropolycyclic compounds, 2,6-dinitro-5-methoxy-
7-carbomethoxypentacyclo[5. 3 .0 . 0* • * . CP • i ° . 0* •8]decane has been synthesized. This is a model system which can be used to study (1) the effect of nitro substitution on the photolability of carbon-carbon double bonds and (2) to develop methods for avoiding Haller-Bauer cleavage in cage /3-keto esters when synthesizing polynitro-substituted cage compounds.
2
Wang, Yanjun. "The Synthesis and Chemistry of Polyciclic Cage Compounds." Thesis, University of North Texas, 1994. https://digital.library.unt.edu/ark:/67531/metadc278447/.
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Chapter I describes the synthesis of a trishomocubyl helical tubuland diol and some aspects of its inclusion chemistry. Thus, all three isomers of 4,7-dimethylpentacyclo[6.3.0.0^2,6.0^3,10.0^5,9]undecane-4,7-diol have been prepared and their X-ray structures have been determined. The syn,syn-isomer crystallizes in a double-stranded hydrogen-bonded lattice, while anti,syn-isomer forms a hydrogen-bonded layer lattice. In contrast, the anti,anti-isomer is a new member of the helical tubuland diol host family; its crystal lattice consists of parallel canals with a trefoil-shaped cross-section of area 25.4 Å^2. Chapter II describes the synthesis of new molecular clefts. These molecular clefts have been synthesized via base-promoted reactions of 3,6-diaryl-l,2,4,5-tetrazines with tetracyclo[6.3.0.0^4,11.0^5,9]undecane-3,6-dione and with tricyclo[6.3.0.0^2,6]undecane-3,11-dione, respectively. Compounds of this type are of interest as a potential new class of host molecules for use in host-guest complexation studies. Chapter III reports the synthesis of stereospecifically deuterated spiro(oxetane-3,8'-pentacyclo[5.4.0.0^2,6.0^3,10.0^5,9]undecanes) and their acid-promoted ring opening and concomitant rearrangements. The deuterium-containing reaction products have been characterized via analysis of their NMR and mass spectra. The results strongly suggest that intramolecular 1,5-hydride shifts provide an important pathway through which the acid promoted rearrangements occur. Chapter IV reports the oxidation of heptacyclo-[6.6.0.0^2,6.0^3,13.0^4,11.0^5,9.0^10,14] tetradecane (HCTD) via application of Barton's "GoAgg" systems. The products have been characterized by NMR and mass spectral analysis. Under GoAgg^v conditions, oxidation of HCTD proceeds to afford heptacyclo [6.6.0.0^2,6.0^3,13.0^4,11.0^5,9.0^10,14]tetradecan-7-one in 1% yield.
3
Torres, Costa Eva. "Synthesis of polycyclic compounds with antiviral activity." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/124040.
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Research for new antivirals to treat Influenza A virus infections has gained importance during this last decade due to the imminent danger of an Influenza pandemic. For some years, several new strains of this virus have appeared worldwide causing small outbreaks with a notable relevance, for example the ‘avian flu’ (H5N1 in 2007; H7N9 in 2012) and ‘swine flu’ (H1N1 in 2009), that have triggered the assumption that a new pandemic is coming.
There are several strategies to treat an Influenza A virus infection targeting some of its surface proteins. In this Thesis, several compounds inhibiting the M2 channel of the virus are designed, synthesized and evaluated. Our approach is based on the synthesis of amantadine’s analogues by ring expansion, contraction and rearrangement.
Amantadine is a drug already approved by the FDA for the treatment of Influenza A virus and it is known to target the M2 channel. Although it is no longer in use, because the FDA has recommended against its use, due to the appearance of resistance, it possessed good activity and an acceptable pharmacological behaviour. Our main goal was to synthesize an analogue of amantadine that was able to overcome the resistant virus and provide a new therapeutic alternative to the already marketed neuraminidase inhibitors such as Oseltamivir and Zanamivir.
Importantly, we took advantage of the wide expertise of our research group in synthesizing polycyclic compounds to start a new research field that was based on the application of these optimized synthetic routes to the Medicinal chemistry. We established some external collaboration in order to set up the milestones and to build the rationale of the current project. These new collaborations are the following:
- Prof. Lieve Naesens research group in the Rega Institute for Medical Research in Leuven, Belgium. This group of virologist made the plaque reduction assays and the study of the mutants to establish the mechanism of action of the tested compounds.
- Lawrence H. Pinto research group of the Northwestern University, Evanston, Illinois, USA. This group of biochemist made the patch clamp assay to check if our compounds targeted the M2 channel.
- Prof. Javier Luque of Universitat de Barcelona, Barcelona, España. This group made the docking and molecular dynamics of our compounds.
In the following figures, the general structures of the compounds synthesized in the current Thesis are shown. Several of them showing an outstanding activity that allowed us to publish in the most important journals of the Medicinal Chemistry field:
It it worth to mention that, several compounds have shown better activity than the reference compound, Amantadine. The most distinguished compounds are the following:
Compound 1, 2 and 3 showed a superior activity against H1N1 strain in the cell culture assay while being almost inactive in the patch clamp assay. Prof. Lieve Naesen’s research group tried to identify the mechanism of action of these compounds selecting the mutants of hemagglutinin under the pressure of our compounds, revealing that this protein was the target of the first cluster of molecules.
Compound 4 and 5 showed an outstanding activity against the wild-type and V27A M2 channels of influenza A virus. Taken together, all of these results show that tuning the polycyclic scaffold of amantadine could be the way to overcome the already stated resistance.
A second part of this current Thesis consisted in a collection of compounds that have activity against vaccinia virus. These compounds are analogues of Tecovirimat®, a compound that it is currently in phase III clinical trials. When we started this project, we wanted to explore the impact in the EC50 of changing the polycyclic scaffold of the Tecovirimat® molecule, a common tool used in Medicinal Chemistry. We synthesized nearly 40 compounds and we obtained activities similar to Tecovirimat®, although none of our molecules was better than the reference compound.
4
Murrison, Sarah Louise. "Diversity-oriented synthesis of polycyclic alkaloid-like compounds." Thesis, University of Leeds, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531520.
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Wu, An-hsiang. "Syntheses of Highly Strained Energetic Molecules and Development of New Synthetic Methodology." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc331132/.
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The objective of this study was to synthesize new energetic, strained, saturated polycyclic compounds. For this purpose, new methodology has been developed, as follows: (i) Ketenes have been generated in situ via treatment of aldo-, keto- or alkenoic acid with either toluenesulfonyl chloride or 2-chloro-1-methylpyridfniurn iodide (Mulkaiyama's reagent). The reactive intermediates thereby generated have been found to undergo intramolecular [2+2] cycloaddition reactions in these systems.
6
Ren, Chien-Tai. "Synthesis of Polycyclic "Cage" Molecules." Thesis, University of North Texas, 1989. https://digital.library.unt.edu/ark:/67531/metadc500575/.
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The synthesis of a novel, cage spiro-oxetane was carried out. Pentacyclo[5.4.0.0^2,6.0^3,10.0^5,9]undecane-8- one (PCUD-8-one) undergoes one-carbon homologation to a mixture of endo- and exo- PCUD-carboxaldehydes which then are converted into 8,8-bis(hydroxymethyl)PCUD. The monotosylate obtained via reaction of 8,8- bis(hydroxymethyl)PCUD with tosyl chloride(1 equivalent) reacts with sodium hydride to afford the corresponding spiro-oxetane via intramolecular Williamson reaction. Six new substituted heptacyclo[6.6.0.0^2,6.0^3,13.0^4,11. 0^5,9.0^10,14]tetradecanes (HCTD) were synthesized. These compounds will be used as substrates in a photoelectron spectroscopic study. The ring-expansion reaction of PCUD-8-one with ethyl diazoacetate in the presence of BF_3:OEt_2 was performed. The major product was converted into an alcohol, and the structure of the 3,5-dinitrobenzoate of this alcohol was elucidated by single crystal x-ray structural analysis.
7
Zhao, Dalian. "Syntheses and the Structures of Polymethylpolycyclic and Polycyclic "Cage" Molecules." Thesis, University of North Texas, 1989. https://digital.library.unt.edu/ark:/67531/metadc500344/.
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The structures of Diels-Alder cycloaddition of cyclopentadiene to 2,6-dimethyl-p-benzoquinone and methylcyclopentadiene to 2,6-dimethyl-p-benzoquinone were assigned by analysis of 1-D and 2-D proton and carbon-13 NMR spectra. The structures of the cycloadduct of methylcyclopentadiene to 2,6-dimethyl-p-benzoquinone and that of the corresponding intramolecular [2+2] photocyclization product were also obtained by single crystal X-ray structural analysis. As the second part of the study, a new polycyclic "cage" molecule, a substituted trishomocubane isomer, was synthesized. In this synthesis, reductive bond cleavage followed by Dieckmann condensation was employed. Wolff-Kishner reduction then was used to convert a β-keto ester "cage" molecule to the corresponding carboxylic acid. A compound that possesses twofold symmetry was isolated from reaction product mixture. The structure of this compound has been established by single crystal X-ray crystallography.
8
Cho, Don Mark. "Partially fluorinated polycyclic aromatic compounds synthesis and supramolecular behavior /." Lexington, Ky. : [University of Kentucky Libraries], 2006. http://lib.uky.edu/ETD/ukychem2007t00544/Cho_thesis.pdf.
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Thesis (M.S.)--University of Kentucky, 2006.Title from document title page (viewed on February 27, 2007). Document formatted into pages; contains: xiv, 69 p. : ill. (some col.). Includes abstract and vita. Includes bibliographical references (p. 64-68).
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Cho, Don Mark. "PARTIALLY FLUORINATED POLYCYCLIC AROMATIC COMPOUNDS: SYNTHESIS AND SUPRAMOLECULAR BEHAVIOR." UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_theses/443.
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The field of organic electronics has received much attention over the last few years, and engineering of organic crystals to grow with pi-electron systems arranged in a face-to-face motif has been shown to be beneficial in electronic devices. The effects of combining aromatic and perfluorinated aromatic derivatives have shown that the intramolecular stacking pattern can be changed from an edge-to-face arrangement to that of a face-to-face motif. Before the work described herein, there were no reported studies of the supramolecular behavior of fused polycyclic aromatic compounds with partial peripheral fluorination, inducing the desired face-to-face behavior. This is the main focus of the thesis. Furthermore, by exploiting the interactions between the fluorinated and non-fluorinated faces of the molecule, columnar liquid crystalline behavior can be achieved through variations of the alkyl substituents on the molecule.
10
Chaolumen. "Synthesis and Properties of Electron-Deficient Polycyclic Aromatic Compounds." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225617.
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Eichholzer, Astrid <1978>. "Stereoselective Catalytic Processes for the Synthesis of Polycyclic Aromatic Compounds." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2398/.
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In this PhD-thesis, two methodologies for enantioselective intramolecular ring closing reaction on indole cores are presented. The first methodology represents a highly stereoselective alkylation of the indole N1-nitrogen, leading to 3,4-dihydro-pyrazinoindol-1-ones – a structural class which is known for its activity on the CNS and therefore of high pharmacological interest concerning related diseases. In this approach, N-benzyl cinchona-alkaloids were used for the efficient catalysis of intramolecular aza-Michael reactions. Furthermore, computational studies in collaboration with the research group Prof. Andrea Bottoni (Department of Chemistry “G. Ciamician”, Bologna) were accomplished in order to get insight into the key interactions between catalyst and substrate, leading to enantiomeric excesses up to 91%. The results of the calculations on a model system are in accordance with the experimental results and demonstrate the high sensibility of the system towards structural modifications.
The second project deals with a metal catalyzed, intramolecular Friedel-Crafts (FC)-reaction on indolyl substrates, carrying a side chain which on its behalf is furnished with an allylic alcohol unit. Allylic alcohols are part of the structural class of “π-activated alcohols” – alcohols, which are more easily activated due to the proximity to a π-unit (allyl-, propargyl-, benzyl-). The enantioselective intramolecular cyclization event is catalyzed efficiently by employment of a chiral Au(I)-catalyst, leading to 1-vinyl- or 4-vinyl-tetrahydrocarbazoles (THCs) under the formation of water as byproduct. This striking and novel process concerning the direct activation of alcohols in catalytic FC-reactions was subsequently extended to similar precursors, leading to functionalized tetrahydro-β-carbolines.
These two methodologies represent highly efficient approaches towards the synthesis of scaffolds, which are of enormous pharmaceutical interest and amplify the spectra of enantioselective catalytic functionalisations of indoles.
12
Chong, Hyun-Soon. "Explorations with Polycarbocyclic Cage Compounds." Thesis, University of North Texas, 1999. https://digital.library.unt.edu/ark:/67531/metadc2218/.
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A variety of novel cage-functionalized pyridyl containing crown ethers have been prepared for use in selective alkali metal complexation studies. A highly preorganized, cage-functionalized cryptand also has been designed and has been synthesized for use as a selective Li+ complexant. The alkali metal picrate extraction profiles of these cage-functionalized crown ethers also have been studied. Novel cage-functionalized diazacrown ethers have been prepared for selective alkali metal complexation studies. Alkali metal picrate extraction experiments have been performed by using this new class of synthetic ionophores to investigate the effects of cage-annulation and the influence of N-pivot lariat sidearms upon their resulting complexation properties. Novel pyridyl containing calix[4]arene receptors were prepared. Analysis of their respective 1H NMR and 13C NMR spectra suggests that calix[4]arene moieties in the ligand occupy the cone conformation. The complexation properties of these host molecules were estimated by performing a series of alkali metal picrate extraction experiments. An optically active cage-functionalized crown ether which contains a binaphthyl moiety as the chiral unit was prepared. The ability of the resulting optically active crown ether to distinguish between enantiomers of guest ammonium ions (i.e., phenylethylamonium and phenylglycinate salts) in transport experiments was investigated. Hexacyclo[11.2.1.02,12.05,10.05,15.010,14]hexadeca-6,8-diene-4,11-dione was prepared from hexacyclo[7.4.2.01,9.03,7.04,14.06,15] pentadeca-10,12-diene-2,8-dione. Unanticipated but remarkable acid and base promoted rearrangements of this new cage dione to novel polycyclic systems were observed and subsequently were investigated. The structures of the new systems thereby obtained were determined unequivocally by application of X-ray crystallographic methods. It is noteworthy that the reactions reported herein each provide the corresponding rearranged product in high yield in a single synthetic step. Pi-facial and regioselectivity in the thermal Diels-Alder cycloaddition between hexacyclo[11.2.1.02,12.05,10.05,15.010,14]hexadeca-6,8-diene- 4,11-dione and ethyl propiolate have been explored. This reaction proceeds via stereospecific approach of the dienophile toward the syn face of the diene p -system. However, [4+2]cycloaddition proceeds with only modest proximal/distal regioselectivity. The structure of the minor reaction product was established unequivocally via application of X-ray crystallographic techniques.
13
Zhang, Ruoxin. "Toward the synthesis of polycyclic aromatic compounds as nano-carbon cages." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5617.
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Thesis (M.S.)--West Virginia University, 2008.Title from document title page. Document formatted into pages; contains vii, 45 p. : ill. Includes abstract. Includes bibliographical references (p. 24-26).
14
Ota, Yusuke. "Synthesis of Nitrogen-Containing Polycyclic Compounds through Copper-Catalyzed Multi-Component Reaction." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/120509.
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Dong, Hongchen. "Synthesis of hyperbranched polyarylenes and poly(aroylarylene)s by polycyclotrimerization of alkynes and their applications as photoresist and precursors for magnetic ceramics /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202005%20DONG.
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Tatsuya, Nakano. "Synthesis and Functionalization of Fused Aromatic Ring-layered Compounds." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199330.
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Tsay, Fuh-Rong. "Synthesis and 2-D NMR Analysis of a New Phenyl-Substituted Polycyclic Compound." Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc504049/.
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Diels-Alder [4+2] cycloaddition of a mixture of 1- and 2 methylcyclopentadiene to 2-phenyl-g.-benzoquinone affords a mixture of four nd cycloadducts. A single, isomerically pure cycloadduct was isolated by careful column chromatography. Stereospecific reduction of this material with sodium borohydride and cerium(III) chloride 'affords a single, isomerically pure tricyclic diol. The structures of the cycloadduct and this tricyclic diol, established via analysis of their one- and two-dimensionial NMR spectra, were shown to be (1-methyl-5-phenyltricyclo[6.2.1.02,7]undec a-4,9 diene-3,6-dione and 1-methyl-5-phenyltricyclo[6.2.1.0 2 ,7 ]undeca-4,9-diene t.&A-3-=.a-6-diol), respectively. Intramolecular [2+2] photocyclization of this tricyclic diol afforded the corresponding cage diol, 3-methyl-7phenylpentacyclo[5.4.0.0 2 ,6 .03 , 1 0 .05, 9 ]undecane-.exogxa-8,11-diol. Oxidation of this cage diol with pyridinium chlorochromate in dry dichloromethane afforded a single, isomerically pure cage hydroxyketone, 3-methyl-7 phenylpentacyclo[5.4.02,6.03,l .1519]undecane-xA-8-ol-II-one, whose structure was established by single crystal X-ray crystallographic methods.
18
Hilton, Cameron L. "Biphenyl complexes of zirconium and their utility in the synthesis of polycyclic aromatic hydrocarbons." abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3326203.
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Sharma, Rajan. "Synthesis & biological evaluation of neuroprotective molecules with polycyclic scaffolds." University of the Western Cape, 2017. http://hdl.handle.net/11394/6228.
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Doctor Pharmaceuticae - DpharmAmong neurological disorders, many of the most devastating disorders are neurodegenerative. Modern research associates excitotoxicity to a variety of neuropathological conditions, suggesting that the neurodegenerative diseases with distinct etiologies may have excitotoxicity as a common pathway. Excitotoxicity occurs through over-stimulation of receptors for excitatory neurotransmitters like the N-methyl-D-aspartate (NMDA) receptors. Due to the relevance of NMDA receptors and excitotoxic processes, the antagonism or modulation of NMDA receptors is used as a therapeutic tool against neurodegenerative diseases. NMDA receptor activity can be modulated by S-nitrosylation and this modulation of NMDA receptor activity can be utilised in the development of neuroprotective drugs.
20
Horta, Javier Enrique. "Synthesis of polycyclic heteroaromatic compounds via the intramolecular [4+2] cycloaddition of conjugated hetarenynes and alkynes." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36251.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2006.Vita.
Includes bibliographical references.
This dissertation describes studies of the feasibility and scope of intramolecular [4+2] cycloadditions of hetarenynes and alkynes as a method for the synthesis of polycyclic benzo[b]-fused five-membered heteroaromatic compounds. Only scattered reports of this transformation existed prior to our work and these were very limited in their scope. The research presented in this thesis demonstrates that the synthesis of benzo[b]-fused five-membered heteroaromatic compounds can be effectively carried out under relatively mild thermal conditions utilizing alkynylpyrroles, -thiophenes, or -furans tethered to alkynes. The hetarenyne cycloaddition substrates are readily prepared in 2-3 steps from commercially available or known 2- or 3-halohetarenes via Sonogashira coupling followed in most cases by a Mitsunobu reaction. In the majority of cases metalation of a terminal alkyne with a Grignard reagent and then reaction with various electrophilic reagents allows for the creation of a library of cycloaddition substrates. The scope of the hetarenyne cycloaddition was explored with respect to four major variables in the cycloaddition substrates:
(cont.) (1) the nature of activating groups attached to the alkynyl 2c component; (2) the composition of the tether connecting the 2n and 4 components; (3) the type of hetarene (i.e., pyrrole, thiophene, or furan); and (4) the position of attachment of the tether to the hetarene. The experimental findings can be summarized as follows: (1) electron-withdrawing and electronegative groups attached to the 2 component accelerate the cycloaddition; (2) electronegative heteroatoms within the tether accelerate the cycloaddition; (3) the order of reactivity of hetarenynes is: alkynyl-(N-Boc)pyrrole - alkynylfuran > alkynylthiophene; and (4) attachment of the tether bearing the 2c component at C-2 of the hetarene leads to a more facile reaction than attachment at C-3. Finally, the cycloaddition of substrates having Lewis basic substituents attached to the 27c component can be effectively promoted by the use of Lewis acids under very mild conditions, leading in most cases to an improved yield.
by Javier Enrique Horta.
Ph.D.
21
Zhang, Quan. "Synthesis of o-isotoluenes, o-quinodimethanes, and benzoenynyl carbodiimides and their cyclizations to polycyclic and heterocyclic compounds." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=434.
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Thesis (Ph. D.)--West Virginia University, 1999.Title from document title page. Document formatted into pages; contains xvi, 108 p. : ill. Includes abstract. Includes bibliographical references (p. 98-108).
22
Baghdanov, Vaceli M. "Synthetic studies of naturally occurring hydroxylated polycyclic compounds : daunomycinone and pillaromycinone /." Full text open access at:, 1987. http://content.ohsu.edu/u?/etd,142.
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Xing, Dong, and 邢栋. "Transition metal-catalyzed C-N bond formation via addition of nitrogennucleophiles towards alkenes and related tandem cyclization reactions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46589156.
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Joubert, Jacques. "Fluorescent polycyclic ligands : strategies towards the synthesis and evaluation of fluorescently labelled receptor and enzyme ligands / Jacques Joubert." Thesis, North-West University, 2012. http://hdl.handle.net/10394/10408.
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Neurodegenerative disorders, including Alzheimer's and Parkinson's disease, and the
development of neuroprotective agents have received significant research attention in recent
years. Development of novel imaging techniques to study the biological mechanisms involved
in the progression of these disorders have become an area of research interest. The design of
novel small molecule imaging probes in combination with modem imaging techniques may
provide information on neuroprotective binding site• interactions and would assist in the
design of novel biological assay methods. Techniques to visualize physiological or
pathophysiological changes in proteins and living cells have become increasingly important in
biomedical sciences, especially fluorescent techniques. Fluorescent ligands in combination
with sophisticated fluorescent imaging technologies are useful tools to analyze and clarify the
roles of biomolecules in living cells, affording high spatial and temporal resolution.
This study is based on the development of polycyclic fluorescent ligands, which may be used
in the study of receptor-ligand and/or enzyme-ligand interactions, utilizing these fluorescently
labeled ligands in combination with fluorescent imaging techniques. Fluorescent conjugates
with high affinity for the• N-methyl-D-aspartate (NMDA) receptor, voltage gated calcium
channels (VGCC) and/or the nitric oxide synthase (NOS) enzyme were designed and
synthesised with the aim to directly measure binding of these novel molecules to receptors
and/or enzymes.
The first goal was to develop fluorescent ligands that exhibit similar inhibitory activity on
NOS compared to the well-known selective neuronal NOS inhibitor 7-nitroindazole (7-NI).
Polycyclic compounds, including amantadine and pentacycloundecane derivatives, were
conjugated to fluorescent moieties that resemble the structure of 7-NI. It was thought that the
lipophilic nature of the polycyclic compounds would increase the activity of the fluorescent
moieties by facilitating increased blood brain barrier permeability and penetration through cell
membranes. This would also potentially increase the selectivity of the novel conjugated
compounds as selective neuronal NOS inhibitors, similar to 7-NI. The results from the NOS
inhibition studies indicated that the novel fluorescent conjugates (5-14) inhibited the NOS
enzyme at micromolar concentrations. Although none of the novel fluorescent polycyclic
compounds were found to be more potent than 7-NI (IC50 = 0.11 11M), the indazole
pentacyclorindecane (5), the coumarin-adamantane (7), the dansyl-adamantane (8), and the
cyanoisoindole-adamantane (11) conjugates, exhibited IC5o values below 1 uM. These
compounds could possibly be used as molecular probes in the development of high-throughput
screening or competitive NOS displacement assays. Further studies on isoform
selectivity will elaborate on the potential of these compounds as fluorescent molecular probes.
The aforementioned fluorescent derivatives were further developed resulting in a series of
novel fluorescent polycyclic conjugates with potent NOS inhibition indicating the potential of
these compounds as neuroprotective agents. Due to the polycyclic structure's inherent
inhibitory activity towards the NMDA receptor and VGCC we evaluated these derivatives as
possible multifunctional neuroprotective agents acting on various neuroprotective targets. In
the biological studies it was observed that four adamantane fluorescent compounds (7, 8, 10,
11) exhibited a high degree of inhibitory activity against the NOS enzyme and NMDA
receptor and blocked VGCC. The fluorescent compounds were further able to scavange
detrimental neurodegenerative free radicals. In silica studies also predicted a high degree of
oral bioavailability and that these novel compounds should be effectively transported across
the blood brain barrier.
Taking the positive findings on the inhibition of the NMDA receptor and VGCC activity of
the novel fluorescent polycyclic ligands into account we focused on the expansion of this
series. This resulted in the synthesis of a series of fluorescent derivatives utilizing
adamantane-3-aminopropanol as an intermediate to extend the chain length between the
adamantyl and fluorescent moieties, to potentially reduce sterical hindrance and increase
activity. These novel adamantane-3-aminopropanol fluorescent ligands were also evaluated
for inhibition of the NMDA receptor and VGCC. The coumarin-, dansyl- and cyanoisoindole
adamantane-3-aminopropanol fluorescent conjugates (15, 16, 19) displayed significant VGCC
inhibition, with the dansyl (16) and di-nitrobenzene (20) fluorescent derivatives exhibiting
NMDA receptor antagonistic activity. All these compounds showed improved activity when
compared to known NMDA receptor and VGCC inhibitors in this class. Generally it was
observed that the increased chain length analogues had improved VGCC inhibition and
NMDA receptor activity when compared to their directly• conjugated counterparts. This led to
the conclusion that an increase in chain length might indicate deeper immersion into the
NMDA receptor and VGCC which may be necessary for stronger interaction with their
putative binding sites. The dansyl analogue, N-[3-(1-adamantylamino)propyl]-5-
dimethylaminonaphthalene-1-sulfonamide (16), was further used as a fluorescent NMDA
receptor ligand in a fluorescent competition assay, utilizing known NMDA receptor inhibitors
to demonstrate the possible applications of these novel fluorescent analogues and their benefit
over the use of hazardous and expensive radioligand binding studies.
Further investigation on the application of these derivatives, especially on the NOS enzyme
and the NMDA receptor, will develop their potential as fluorescent ligands in the study of
neurodegeneration and may also yield novel therapeutic agents against neurodegenerative
disorders.PhD (Pharmaceutical Chemistry), North-West University, Potchefstroom Campus, 2012
25
Schäfer, Christian. "Reactivity of acetylenic ω-keto-esters towards transition metal complexes : synthesis of polycyclic motives of natural products." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAF006/document.
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Les travaux décrits dans ce mémoire ont pour objet l’étude de la réactivité des ω-céto-esters acétyléniques vis-à-vis des métaux de transition. Lorsque ces composés sont traités avec une mélange Ti(OiPr)4/iPrMgBr, la formation d’alcools allyliques bicycliques est observée avec une totale diastéréosélectivité par rapport à la jonction de cycle (cis) et une configuration (E) pour la double liaison. Il a été montré que ces produits peuvent être transformés en lactone α,β-insaturé, sous-structures de produits naturels. La cycloisomérisation d’alcynyl cétones catalysées par des sels d’Ag(I) conduit à la formation de composés spiraniques. En piégeant l’intermédiaire réactionnel, la synthèse des composés vinyl-iodés correspondants a été réalisée. Si la réaction de cycloisomérisation est effectuée avec des ω-céto-esters acétyléniques, des ester α,β-insaturés sont isolés. Les produits obtenus ont ensuite été utilisés comme substrats pour la formation de systèmes tricycliques 6-5-5 et 6-6-5. Ces enchaînements de cycles sont présents dans le squelette carboné d’une grande variété de produits naturels. Les travaux décrits dans ce mémoire ont pour objet l’étude de la réactivité des ω-céto-esters acétyléniques vis-à-vis des métaux de transition. Lorsque ces composés sont traités avec une mélange Ti(OiPr)4/iPrMgBr, la formation d’alcools allyliques bicycliques est observée avec une totale diastéréosélectivité par rapport à la jonction de cycle (cis) et une configuration (E) pour la double liaison. Il a été montré que ces produits peuvent être transformés en lactone α,β-insaturé, sous-structures de produits naturels. La cycloisomérisation d’alcynyl cétones catalysées par des sels d’Ag(I) conduit à la formation de composés spiraniques. En piégeant l’intermédiaire réactionnel, la synthèse des composés vinyl-iodés correspondants a été réalisée. Si la réaction de cycloisomérisation est effectuée avec des ω-céto-esters acétyléniques, des ester α,β-insaturés sont isolés. Les produits obtenus ont ensuite été utilisés comme substrats pour la formation de systèmes tricycliques 6-5-5 et 6-6-5. Ces enchaînements de cycles sont présents dans le squelette carboné d’une grande variété de produits naturelsIn this work, the reactivity of acetylenic ω-ketoesters towards different metal complexes was investigated. When acetylenic ω-ketoesters are submitted to Ti(OiPr)4/iPrMgBr, the formation of fused bicyclic γ-hydroxy-α,β-unsaturated esters was observed. The products were obtained with absolute selectivity in regard to the ring junction formed (cis) and the configuration of the double bond (E) and could be transformed into the corresponding α,β-unsaturated lactones, substructures of various natural products. When ω-ketoalkynes are used in Ag(I)-catalyzed cycloisomerization reactions, the formation of spirocyclic compounds was observed. By taking advantage of the reaction intermediates of this reaction, it was possible to isolate the corresponding spirocyclic alkenyl iodides. Performing cycloisomerization reactions with acetylenic ω-ketoesters, spirocyclic α,β-unsaturated esters are formed. We could show that these products are valuable substrates for the formation of 6-5-5- and 6-6-5-fused tricyclic systems which represent the skeleton of a large group of natural products
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Hashimoto, Sigma. "Syntheses of Polycyclic Aromatic Compounds with Heteroatom Junctions via Tandem Hetero-Friedel－Crafts Reactions." 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/174950.
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Giang, Yun-Seng F. (Yun-Seng Frank). "Intramolecular 2+2 Cycloadditions of Ketenes." Thesis, North Texas State University, 1986. https://digital.library.unt.edu/ark:/67531/metadc331159/.
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The objective of this study was to explore intramolecular ketene cycloadditions with the anticipated results of developing new synthetic methodology for the synthesis of polycyclic compounds difficult to obtain by other procedures. (o-Alkenylphenoxy)ketenes were initially selected for this study because these ketenes provided a favorable proximity for the intramolecular [2+2] cycloaddition reactions. The difunctional precursors, (o-alkenylphenoxy)- acetic acids, were readily prepared from o-alkenylphenols and ∝-halocarboxylic acids and were converted to the corresponding acid chlorides by reaction with oxalyl chloride. The acid chlorides were dehydrochlorinated to the corresponding (o-alkenylphenoxy)ketenes by treatment with triethylamine. The ketenes undergo a facile intramolecular [2+2] cycloaddition to give polycyclic eye 1obutanones. The (o-vinylphenoxy)ketenes are clearly more reactive than the (o-allylphenoxy)ketenes and provide much better yields of the cycloaddition products because of electronic effects in the transition state in the cycloaddition process. The intramolecular [2+2] cycloadditions of keteniminium salts were included in this study as a more electrophilic alternative to ketenes that will react with less nucleophilic carbon-carbon double bonds. However, the use of keteniminium salts instead of ketenes in Intramolecular cycloadditions does have some limitations. The synthesis of benzofurans via the intramolecular [2+2] cycloadditions of (o-acylphenoxy)ketenes was accomplished. The initially formed ß-lactone cycloaddition products spontaneously underwent decarboxylation to the benzofurans. The aromaticity of the benzofurans is apparently a very strong driving force for the cycloaddition. During the course of this study, two new synthetic methods were discovered which in many instances represent a significant Improvement over existing methods. The Wittig Reactions of ketoacids without protecting the carboxyl groups provide a reliable source of the precursor unsaturated acids needed for intramolecular ketene-olefin cycloadditions. Also, the one-pot preparation of intramolecular ketene cycloaddition products from the carboxylic acid via the tosylate represents a new synthetic method. This procedure eliminates the acid halide preparation, isolation and purification step, thereby significantly simplifying the synthesis.
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Patil, Dadasaheb V. "Intramolecular cyclization strategies for synthesizing medium-ring polycycles and the total synthesis of natural products." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/50118.
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Carbo- and heterocyclic compounds are of great interest to chemists. Intramolecular cyclization strategies of donor-acceptor (D-A) cyclopropanes and alkylidene malonate monoamides have excellent potential for synthesis as they offer easy access to structurally-diverse compounds. The work described in this thesis accesses the scope of the In(OTf)3-catalyzed cyclization reaction of cyclopropanes and alkylidene malonate monoamides. In(OTf)3-catalyzed reactions of alkenyl and heteroaryl cyclopropyl ketones were examined in the synthesis of functionalized cyclohexenone-based derivatives (Chapter 2). Subsequent efforts to utilize a tandem cyclopropane ring-opening/Friedel-Crafts alkylation sequence of methyl 1-(1H-indolecarbonyl)-1-cyclopropanecarboxylates to prepare functionalized hydropyrido[1,2-a]indole-6(7H)-ones is discussed in Chapter 3. The extension of this tandem protocol towards the total synthesis of (±)-deethyleburnamonine is the subject of Chapter 6. Intramolecular Friedel-Crafts alkylation of N-indolyl alkylidene malonate monoamides was also examined. An In(OTf)3-catalyzed cyclization of substituted methyl 2-(1H-indole-1-carbonyl) acrylates afforded a series of 1H-pyrrolo[1,2-a]indole-3(2H)-ones (Chapter 4), whereas substrates with the indole 2-position blocked provided access to substituted 4H-pyrrolo[3,2,1-ij]quinolin-4-ones (Chapter 5).
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Waske, Prashant Ankushrao. "Radical cation cyclization of cyclopropyl silyl ethers induced by PET: synthetic applications for the construction of polycyclic compounds and Photoacylation of 1,4-naphthoquinones a concise access to the biologically active quinonoid compounds /." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=979951992.
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Lozano, Mena David. "Síntesi de nous compostos policíclics com a possibles precursors d’alquens piramidalitzats." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/404663.
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En la present Tesi Doctoral s’ha desenvolupat una metodologia sintètica per accedir a compostos policíclics complexos funcionalitzats de manera senzilla i eficaç, amb l’objectiu de poder generar a partir d’aquests un alquè piramidalitzat i estudiar el seu comportament químic en condicions específiques de reacció.
En primer lloc, es va posar a punt la síntesi del 5,5-bis(acetoximetil)ciclopenta-1,3-diè, intermedi clau per la introducció de la funcionalització desitjada en l’estructura policíclica. Mitjançant reacció de Diels-Alder entre el ciclopentadiè-1,1-disubstituït i l’acetilè adient (des de l’acetilendicarboxilat de dimetil fins a sals de iodoni triflat o dobles sals de iodoni triflat), es va aconseguir introduir la doble funció veïnal èster metílic, iode-trimetilsilil o iode-iode, grups funcionals clau per la generació d’alquens piramidalitzats.
En el primer capítol d’aquesta tesi, es va introduir la doble funcionalització èster metílic com a model per a la construcció de policicles més complexos. Per metanòlisi bàsica dels grups acetoximetil provinents del ciclopentadiè de partida, es va observar addició de Michael intramolecular i es va formar el 3a-(hidroximetil)-3,3a,4,6a-tetrahidro-1H-1,4- metanociclopenta[c]furan-1,7-dicarboxilat de dimetil, donant lloc a diastereòmers. A partir d’aquest esquelet, transformant-lo en el derivat iodometil, es va poder estudiar la reacció Domino de substitució nucleòfila (mitjançant ciclopentadienur potàssic com a nucleòfil) i posterior reacció de Diels-Alder intramolecular. Reacció Domino per la qual es generen tres nous enllaços C–C i tres nous anells, resultant així en un hexacicle funcionalitzat. Es va aconseguir evitar parcialment la reacció de Michael intramolecular realitzant la hidròlisi en medi àcid, fet que va permetre l’obtenció del (1R,4S)-7,7-bis(iodometil)biciclo[2.2.1]hepta-2,5- diè-2,3-dicarboxilat de dimetil, del qual es va poder estudiar la doble reacció Domino de substitució nucleòfila seguida de Diels-Alder intramolecular. Aquesta metodologia va permetre la creació de sis nous enllaços C–C i sis nous cicles, obtenint així un octacicle funcionalitzat en una sola etapa basat en la subestructura d’octaciclo[10.6.1.01,10.03,7.04,9.08,19.011,16.013,17] nonadecà, a partir d’un bicicle.
Aplicant aquesta metodologia es va obtenir un octacicle amb la funció iode-trimetilsilil veïnal i en posició cap de pont, possible precursor d’alquens piramidalitzats. Tots els intents de desililació utilitzant diverses fonts de fluorurs no van resultar en la generació de l’alquè piramidalitzat, ja que el grup trimetilsilil va resultar ser inert enfront d’anions fluorurs per impediment estèric. Proves per promoure la generació de l’alquè piramidalitzat utilitzant un catalitzador de pal· ladi per addició oxidant a l’enllaç carboni-iode, no van resultar satisfactòries, però van donar lloc a la co-ciclotrimerització de l’octacicle de partida amb dues unitats d’acetilendicarboxilat de dimetil en un dels dobles enllaços de l’esquelet de partida.
Per últim, s’ha pogut estudiar la reactivitat de l’alquè piramidalitzat en l’esquelet de octaciclo[10.6.1.01,10.03,7.04,9.08,19.011,16.013,17]nonadecà per reacció de l’octacicle diiodat amb t- BuLi, amalgama líquida de sodi, o sodi fos a reflux d’1,4-dioxà. En cap cas l’alquè piramidalitzat ha donat lloc a adductes de cicloaddició [4+2] en presència de diens. Utilitzant reactius organolítics, l’alquè piramidalitzat només ha experimentat addicions nucleòfiles del grup t-Butil. Mitjançant reacció amb amalgama de sodi o sodi fos, s’han pogut aïllar el producte de reducció de l’alquè piramidalitzat, un dímer, i un producte derivat de reacció amb el dissolvent de la reacció.A fast and simple synthetic methodology to prepare complex polycyclic compounds as potential precursors of a hindered pyramidalized alkene, has been developed. The key steps are: (1) the preparation of cyclopenta-2,4-diene-1,1-diyl(bismethylene) diacetate, (2) Diels-Alder reaction of the above diene with different acetylenic dienophiles [dimethyl acetylenedicarboxylate, (2- trimethylsilylethynyl)phenyliodonium triflate and ethine-1,2-diylbis(phenyliodonium) ditrifalte] leading to norbornadienes that contain two acetoxymethyl groups at position 7 and two vicinal methoxycarbonyl, two vicinal iodine atoms or vicinal iodine and trimethylsilil functionalization at positions 2 and 3. The acetoxymethyl groups of the resulting norbornadienes were transformed into iodomethyl, and were reacted with the potassium salt of cyclopentadiene to give octacyclic compounds derived from a double domino nucleophilic substitution / Diels-Alder reaction, which contain the octacyclo[10.6.1.01,10,03,7.04,9.08,19.011,16.013,17]nonadecane skeleton. The octacyclic compound containing an iodine and a trimethylsilyl group in vicinal bridgehead position, could not be transformed into the desired pyramidalized alkene on reaction with different fluoride anion sources, and under different reaction conditions. Only reactions on the less hindered C=C bond of this compound were observed as well as the substitution of the iodide by a fluoride in several derivatives. The octacyclic compound containing two iodine atoms gave the pyramidalized alkene on reaction with molten sodium in boiling 1,4-dioxane, sodium amalgam, or t-BuLi. However, when these reactions were carried out in the presence of dienes such as 1,3- diphenylisobenzofuran, anthracene or 11,12-dimethylene-9,10-ethanoanthracene, no Diels- Alder adducts were ever observed. When t-BuLi was the organolithium reagent used to generate the pyramidalized alkene, only the product of t-butyl and hydrogen addition was obtained. Under molten sodium or sodium amalgam, the main adduct detected was the product of reduction of the strained alkene. Only a dimer of the pyramidalized alkene was isolated and fully characterized on reaction with sodium amalgam, and under refluxing dioxane, the product of insertion of the solvent could be isolated as a diastereomeric mixture. These results differ from those previously reported with related pyramidalized alkenes, due to the steric hindrance experienced by the pyramidalized alkene generated in the octacyclo[10.6.1.01,10,03,7.04,9.08,19.011,16.013,17]nonadecane skeleton
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Robert, Antoine. "Synthèse organique de macrocycles conjugués par réaction de Perkin." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0935/document.
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La synthèse organique contrôlée de nanobagues de carbone est un challenge scientifique de longue date. Ces composés polycycliques aromatiques cylindriques peuvent être définis comme des sections de nanotubes de carbone plus larges qu’épaisses ; et la courbure de leur système pi pourrait leur conférer des propriétés électroniques intéressantes.Depuis quelques années, notre équipe développe une approche générale de synthèse de composés aromatiques polycycliques fonctionnalisés par des fonctions carboxyliques. Cette approche repose sur la réaction de Perkin entre des acides aryle-acétiques et des acides aryle-glyoxyliques, qui va permettre l’assemblage de ces briques élémentaires en longs précurseurs flexibles mais conjugués. Une dernière étape de cyclisation intramoléculaire, ou « graphitisation », pourra alors conjuguer complètement et donc rigidifier la molécule finale. Cette approche a permis la synthèse de plusieurs nouveaux composés aromatiques polycycliques linéaires.L’objectif de cette thèse est l’adaptation de l’approche de Perkin à la formation de nanobagues aromatiques. Un premier défi a été efficacement remporté avec l’obtention et la caractérisation complète de plusieurs macrocycles flexibles mais conjugués. Certains de ces macrocycles ont même été formés avec d’excellents rendements grâce à la mise en place d’une technique de haute dilution. Plusieurs tentatives de graphitisation ont été menées sur ces composés, impliquant différentes techniques de synthèse telles que la photochimie ou la catalyse au palladium, mais ne permirent malheureusement pas la formation des nanobagues aromatiques désirées. Néanmoins, en modifiant la structure initiale de certaines briques élémentaires nous avons pu obtenir d’autres macrocycles conjugués plus flexibles qui, après photocyclisation, ont abouti à la formation d’autres macrocycles conjugués présentant des structures rigides mais atypiques car non planesThe controlled organic synthesis of carbon nanobelts has been scientific challenge for a long time. Such cylindrical polycyclic aromatic compounds can be defined as sections of carbon nanotubes that are larger than wide. Interesting electronic properties could result from the curvature of their pi system.These last years, our team has developed a general synthetic approach for the formation of carboxy-functionalised polycyclic aromatic compounds. This approach involves the Perkin reaction of arylacetic acids with arylglyoxylic acids, in order to form conjugated and flexible elongated precursors. The last step is an intramolecular cyclisation, or “graphitisation”, which rigidifies the precursor and yields a fully conjugated final molecule. Applying this approach, our team has synthesised several new linear polycyclic aromatic compounds.The aim of this thesis is to adapt the Perkin reaction for the formation of aromatic nanobelts. A first challenge has been solved by synthesising and fully characterising several flexible and conjugated macrocycles. Some of those macrocyclic compounds have been obtained with unexpectedly good yields using a high dilution addition technique. Graphitisations have been tried on some of those macrocycles by different synthetic methods, i.e. photochemistry and palladium catalysis, but none of them led to the formation of the desired aromatic nanobelt. However, by modifying the initial structure of some of the building blocks, we obtained more flexible conjugated macrocycles, which then reacted, by photocyclisation, to form conjugated and non-planar rigid macrocycles with atypical structures
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Reginato, Nada McGlinchey Michael J. "Polycyclic compounds of manganese /." *McMaster only, 2003.
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Pantaine, Loïc. "Aminocatalyse et Réactions en Cascade pour la Synthèse de Polycycles Tridimensionnels." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV084/document.
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Les travaux exposés dans ce manuscrit ont pour objectif d’étudier des séquences réactionnelles organocatalysées permettant la formation stéréosélective de liaisons carbone-carbone ou carbone-hétéroatome. Plusieurs stratégies ont été développées pour la préparation d’architectures cycliques chirales dont la synthèse représente un enjeu important en raison de leur présence dans un grand nombre de molécules d’intérêt biologique. Le manuscrit débute par une introduction sur le principe de l’organocatalyse en se focalisant sur les différents modes d’activation en aminocatalyse.Le premier chapitre traite de la synthèse, sans solvant, régio- et diastéréosélective de bicycles comportant une hydrazine cyclique. Le deuxième chapitre combine la désaromatisation ou la désymétrisation à une séquence aminocatalysée, pour former des polycycles tridimensionnels énantio-enrichis à partir d’aldéhydes insaturés. Enfin, le troisième chapitre se concentre sur la synthèse de sulfamides non symétriques et leur utilisation comme substrats en aminocatalyseThe work presented in this manuscript aims to study organocatalytic reaction sequences enabling the stereoselective formation of carbon-carbon and carbon-heteroatom bonds. Various strategies have been developped for the preparation of chiral cyclic architectures, which represents an important challenge due to their presence in a vast number of biologically active compounds. This manuscript starts off by introducing the principal of organocatalysis, and more specifically the different activation means used in aminocatalysis.The first chapter focuses on the regio- and diastereoselective synthesis of cyclic hydrazine-containing bicycles in a solvent-free way. The second chapter merges de-aromatization or desymetrization with an aminocatalytic reaction sequence, to yield tridimensional enantioenriched polycycles from unsaturated aldehydes. Lastly, the third chapter concentrates on the synthesis of unsymmetrical sulfamides and their uses as substrates in aminocatalysis
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Freeman, David John. "Polycyclic aromatic compounds in flames." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308234.
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Tucker, Sheryl A. (Sheryl Ann). "Spectroscopic Properties of Polycyclic Aromatic Compounds." Thesis, University of North Texas, 1994. https://digital.library.unt.edu/ark:/67531/metadc278682/.
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The fluorescence spectrum of many polycyclic aromatic compounds (PACs) depends upon solvent polarity. The emission spectrum of PAC monomers consists of several major vibronic bands labeled I, II, etc., in progressive order. Emission intensity enhancement of select bands is observed in polar solvents.
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Edwards, W. D. "Synthesis of polycyclic orthoamides." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370413.
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Warner, Stephanie D. "Photochemical degradation of selected polycyclic aromatic compounds." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84446.
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Polycyclic aromatic hydrocarbons and many of their derivatives are considered to be ubiquitous environmental pollutants, which often exhibit mutagenic and/or carcinogenic activity. In the atmosphere, photolysis is generally considered to be the dominant degradation pathway for these pollutants. The photochemical behaviours of benzo(a)pyrene, benzo(b)fluoranthene and benzo(k)fluoranthene have been examined in the laboratory. This study was complemented by an analysis of ambient air samples collected in the vicinity of a Horizontal Stud Soderberg aluminum smelter in Beauharnois, Quebec. Benzo(a)pyrene is much more reactive in the presence of light when compared to the fluoranthene compounds. The products were identified as the 1,6-, 3,6- and 6,12-benzo(a)pyrenediones. An analysis of the ambient air samples revealed the prevalence of benzo(b)fluoranthene in the emissions from the aluminum smelter. Its relatively high abundance and resistance to degradation indicates that it will be a suitable indicator to represent total polycyclic aromatic hydrocarbon levels at the smelter. The photochemical behaviour of a series of nitropolycyclic aromatic hydrocarbons has also been investigated. The photoreactivity of these compounds in solution and adsorbed onto a surface has previously been associated with the torsion angle of the nitro group with respect to the aromatic moiety. Initially, through a combination of spectroscopic techniques and semi-empirical calculations, the orientation of the nitro group in each compound was determined. Solution studies were inconclusive in determining the role of the torsion angle of the nitro group in influencing the photochemical degradation. However, when the compounds were adsorbed onto a surface, no relationship could be established between photoreactivity and the orientation. The stability of these compounds was also examined during the sampling process. In an effort to further examine the relationship between th
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Branan, Bruce Monroe. "The chemistry of polycyclic and spirocyclic compounds /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487849696968107.
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Vayer, Marie. "Approches éco-compatibles en catalyse homogène : développement de nouvelles méthodologies de synthèse pour la formation de molécules complexes." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS444/document.
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Grâce à l’utilisation de catalyseurs sacrifiables issus, la plupart du temps, du groupe principal ou de la première période des éléments de transition, des nouvelles méthodologies de synthèse pour accéder à des molécules complexes ont été développées au cours de cette thèse. i) Des bicyclolactones ont été synthétisées par addition intramoléculaire de β-cétoesters sur des diènes-1,3 catalysée par un système coopératif de Bi(OTf)₃ et d’HOTf. ii) le motif 7-alcynylcycloheptatriène a été étudié et a permis d’accéder sélectivement à différents produits issus soit d’une cycloisomérisation d’énynes-1,6 ou d’une hydroarylation d’allènes, en fonction du caractère dur ou mou de l’acide de Lewis utilisé. iii) Ce motif a ensuite été utilisé comme plateforme pour accéder à des molécules polycycliques en présence d’acides de Lewis ou à des bromophénylallènes en présence d’un agent de bromation. Les bromoallènes ainsi formés ont pu être engagé dans des réactions de couplages C-C et C-N ou dans une réaction de CH-propargylation. iv) La N-éthylation réductrice d’imines en présence d’éthanol et d’un complexe de fer facilement accessible a été étudiée et a conduit à la formation d’amines tertiaires portant trois substituants différentsDue to the use of sacrificial catalysts, most of the time derived from main group elements or 1st row transition metal, new methodologies were developed in this thesis to access complex molecules. i) Bicyclolactones were synthesized by an intramolecular addition of β-ketoesters into 1,3-dienes catalyzed by a cooperative Bi(OTf)₃ / HOTf catalytic system. ii) The 7-alkynylcyclohepatriene moiety was studied and afforded different products provided by a cycloisomerization of 1,6-enynes or an hydroarylation of allenes. The selectivity of this reaction is dependent of the soft or hard character of the Lewis acids engaged. iii) Afterward, the 7-alkynylcycloheptatriene moeity was used as a plateform to access various polycyclic molecules in presence of Lewis acids or bromophenylallenes in presence of a bromation agent. Thus the bromoallene formed can be engaged in C-C and C-N cross coupling reactions or in a CH propargylation reaction. iv) The reductive ethylation of imines using ethanol and a simple iron complex was developed and led to the formation of tertiary amines with three different substituents
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Davies, Ilona Lynn. "Analysis of polycyclic aromatic compounds by multidimensional chromatography." Thesis, University of Leeds, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328575.
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Tyszka, Joanna Helen Margaret. "Towards the synthesis of polycyclic peptides." Thesis, University of York, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282302.
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Kendall, Nigel Lincoln. "Nuclear magnetic resonance study of new polycyclic phosphorus compounds." Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481631.
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Wagner, Svenja. "Teratogenic and Embryotoxic Effects of Polycyclic Aromatic Compounds Report." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-50460.
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Polycyclic aromatic compounds are ubiquitously distributed pollutants in the aquatic and terrestrial environment containing harmful properties on creatures such as carcinogenicity, teratogenicity and toxicity, but are not so well analyzed yet. In the present study, the embryotoxic and teratogenic effects of selected hydroxylated and methylated PACs on the embryonal development of Danio rerio as an aquatic model organism were analyzed with the Fish Embryo Toxicity Test (FET) and the Tail Length Test (TLT) to obtain information on the toxic and teratogenic impact of the tested PACs on the environment. Two of the five tested PACs, 9-MA and DMBA, showed embryotoxic respectively teratogenic effects on the embryonal development of the zebrafish. The embryotoxicity of 9-MA was indicated in the high mortality rate of the exposed zebrafish embryos, whereas the teratogenic effect of DMBA was revealed in the emergence of sub-lethal malformations during the embryonal development such as a shortened tail length, tail curvatures, tail tip deformity or the formation of edema on the yolk sac and pericard as well as abnormal heartbeat and blood circulation. The high mortality rate of the zebrafish embryos exposed to 9-MA did not increase over the exposure time of 96h, which suggests that the chorion of the zebrafish egg could not protect the embryo at all against the strong embryotoxic effect of 9-MA. The sub-lethal malformations of the zebrafish embryos exposed to DMBA could be induced to the metabolic activation of AhR-agonist DMBA through the AhR-pathway or the accumulation of the neurotransmitter Acetylcholine due to the inhibitory function of DMBA on the ACh-Esterase, which caused a neuromuscular system defect or uncontrolled contractions of the axis musculature. Further research, may focus on the mode of action of PACs such as 9-MA and DMBA and their impact on organisms in order to take reasonable precautions to avoid or to diminish the uptake of PACs from the environment.
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Ciochina, Roxana. "STUDIES TOWARD SYNTHESIS OF POLYCYCLIC POLYPRENYLATED ACYLPHLOROGLUCINOLS." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_diss/291.
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Polycyclic polyprenylated acylphloroglucinols (PPAPs) are a class of compounds that reveal intriguing biological activities and interesting and challenging chemical structures. These products are claimed to possess antioxidant, antiviral, and antimitotic properties. Increasing interest is related to their function in the CNS as modulators of neurotransmitters associated to neuronal damaging and depression. All these features make PPAPs targets for synthesis. We decided to focus our own initial efforts in this area on the type A PPAP, nemorosone because we thought that its fairly simple structure relative to other PPAPs would present fewer hurdles as we developed our methodology.In the past decade many approaches to the synthesis of the bicyclo[3.3.1]nonane-2,4,9-trione structure of type A PPAPs have been reported, but only two total syntheses of any PPAP, garsubellin A by Shibasaki and Danishefsky, have been published recently, near the end of 2005. All approaches have relied on the ??,????-annulation of a three-carbon bridge onto a cyclohexanone, although the methods used to execute this annulation differ dramatically. The methods most often used to form the two new C–C bonds have involved classical carbonyl chemistry.We have developed a short and efficient synthetic approach to the bicyclo[3.3.1]nonane skeleton of the PPAPs that involves a novel three-carbon ??,????-annulation of a sterically hindered cyclic ??-keto ester with 3,3-diethoxypropyne. The alkynylation reaction permits the construction of the two contiguous quaternary centers of the PPAPs in reasonable yield and without complications from side reactions. We have also successfully applied a recently developed syn hydrosilylation to the very hindered product of this alkynylation reaction. Our methodology received positive feedback already, and we see this total synthesis of nemorone as an ideal platform for the implementation of new synthetic methodologies.
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Hempenstall, Francis. "Chemoenzymatic synthesis of polycyclic aromatics and derivatives." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287469.
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Carter, Steven Robert. "The synthesis of polycyclic peptide host molecules." Thesis, University of York, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359259.
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Robertson, Charles Ray. "Chemistry towards curved polycyclic aromatic hydrocarbons." abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1438911.
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Fletcher, Kristin A. "Mobile Order Theory as Applied to Polycyclic Aromatic Heterocycles." Thesis, University of North Texas, 1997. https://digital.library.unt.edu/ark:/67531/metadc278994/.
Full textAbstract:
Experimental mole fraction solubilities of benzil, thianthrene, trans-stilbene, thioxanthen-9-one, diphenyl sulfone and dibenzothiophene sulfone are determined in pure noncomplexing and complexing solvents. Predicted solubility values are calculated for benzil, thianthrene, trans-stilbene and thioxanthen-9-one using expressions derived from Mobile Order theory. Large deviations between experimental and predicted solubilities in alcohol solvents exist, therefore optimized solute - solvent association constants are determined. Previously measured thianthrene solubilities in five binary alkane + cyclohexane solvent mixtures are compared with values predicted from Mobile Order theory using the measured solubility in each of the pure solvents as input parameters. The experimental mole fraction solubility of benzil in eight binary alcohol + 1-octanol solvent mixtures are also measured and compared with predicted values.
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Blumire, Nigel James. "Intramolecular radical additions to aromatic compounds." Thesis, University of Southampton, 2003. https://eprints.soton.ac.uk/420074/.
Full textAbstract:
This thesis is concerned with the development of cyclisation strategies that allow entry to polycyclic heterocycles and medium sized ring systems. Radical additions to pyridines are developed and methodologies explore the differences between the homolysis of C-Br and C-I bonds. Mechanisms are described for the unexpected ipso additions to the pyridines. Work towards the synthesis of the stegnans and dimethylgomisin illustrates the attempts to utilise the ipso addition to form medium sized ring systems. A new method of synthesising these medium sized ring systems is discussed. Progress towards a general methodology is described and shows the opportunities for which it could be utilised. A literature review of the synthesis of heterocycles via radical cyclisations is presented.
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Lu, Mingming. "Formation and growth of polycyclic aromatic hydrocarbons by cyclopentadienyl moieties in combustion." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/32824.
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