Dissertations / Theses: 'Heterocyclic compounds – Synthesis'

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Wilson, Jennifer M. "Synthesis of biologically active heterocyclic compounds." Thesis, University of Glasgow, 2007. http://theses.gla.ac.uk/45/.

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More than 11 million people worldwide are diagnosed with cancer every year. New cancer drugs are required that are more effective and selective. Nitrogen mustard alkylating agents crosslink DNA inhibiting transcription and replication. Use of the mustard pharmacophore as part of a macrocycle allows metal complexation and produces a prodrug. Hypoxic tumour cells have increased concentrations of reductase enzymes which could lead to reduction of the complex in situ and release of a cytotoxic drug. Human African Trypanosomiasis is commonly known as Sleeping Sickness and affects over 36 countries of sub-Saharan Africa. It is transmitted to humans by the tsetse fly which carries the parasitic subspecies Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense. Any compounds synthesised would also be tested to assess their potential as anti-parasitic agents. Parker synthesised a range of polyazamacrocycles. Testing of compound A in vitro gave highly efficient DNA crosslinking activity. Copper complexes were formed of the macrocycles and B was found to be 24 times more toxic against hypoxic cells than oxic cells thus exploiting tumour hypoxia and creating a selective drug. Jones synthesised a range of oxaazamacrocycles such as C which when tested in vitro exhibited comparable cross-linking activity to the azamacrocycles although it proved impossible to synthesise the corresponding copper complexes. It was decided to vary the leaving group on the alkylating arms to see if the DNA crosslinking results could be improved. Eight carbamates and the corresponding copper complexes were synthesised. The R-groups were alkyl and aromatic. Anti-cancer DNA crosslinking and hypoxia selectivity results were disappointing however, a number of compounds displayed significant activity when tested against T. brucei. A range of thiaazamacrocycles would complete the set of heteroatom-containing macrocycles (N, O, S) and might produce good DNA crosslinking results. It might also be possible to synthesise the corresponding copper complexes producing prodrugs. Six thiaazamacrocycles were synthesised and 2-hydroxyethyl arms were attached. However it proved impossible to isolate the desired alkylating agents with the 2-chloroethyl arms. In the body, the p53 protein activates the transcription of specific genes. In healthy cells, the levels of p53 have to be kept to a minimum to allow the normal running of the cell, e.g. growth and replication. This function is carried out by the HDM2 protein, which forms an auto-regulatory feedback loop with p53. In some tumours, the p53 function is disrupted due to genetic mutations of p53. However other tumours possess ‘wild type’ p53 – this type of p53 has lost the ability to respond to oncogenic stress due to over-expression of HDM2. Drugs that inhibit HDM2 should cause stabilisation of p53 and induce apoptosis in cancer cells. A small library of 5-deazaflavins were synthesised and biologically tested producing some interesting biological results.

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Jamalis, Joazaizulfazli. "Synthesis of heterocyclic containing oxygen compounds." Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529847.

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Emans, John. "Synthesis of novel heterocyclic polymers." Thesis, University of St Andrews, 1987. http://hdl.handle.net/10023/15299.

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This work details the synthesis, characterisation and fabrication of a range of copolyesters, containing various angular disrupters, especially disubstituted 2,5-diphenyl- -1,3,4-oxadiazoles. These disrupters were incorporated into the polymers, to reduce the temperature at which the polymers may be processed, to enable their fabrication into fibres. The majority of the polymers prepared were found to be liquid crystalline. However, if the angular disrupter content of the polymer was high, it was found that the resultant polymers were non-liquid crystalline. The polymers were prepared by a melt acidolysis process carried out under a nitrogen flow and subsequently under vacuum, as described in Chapter 3. Eighteen of the polymers were characterised in some detail, though a measure of the relative molecular weights was thought to be of little importance in this work, since all polymers were of a different composition. Differential scanning calorimetry and hot-stage microscopy revealed that several of the polymers had rather unusual melting behaviour. The eighteen polymers that were closely characterised were spun into fibres, using a small melt-spinning apparatus that was designed and produced by Bradford University Research Ltd, The resultant fibres were characterised by differential scanning calorimetry, X-ray diffraction end tensile testing. The general conclusion of the work is that although a reduction in the processing temperature of the polymer is achieved by the incorporation of angular disruptors, which is advantageous, the tensile strength and thermal stability of the fibres produced from such polymers are reduced.

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李安怡 and On-yi Lee. "Synthesis of heterocycles via phenylseleno group transfer radical cyclization and chemoselective reductive amination promoted by InCl3." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B3955756X.

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Leu, Chao-Wei Chemistry Faculty of Science UNSW. "Synthesis of heterocyclic analogues of phytoestrogens." Publisher:University of New South Wales. Chemistry, 2008. http://handle.unsw.edu.au/1959.4/40824.

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The pyrrolo[3,2,1-ij]quinolin-6-one ring system was synthesised from 3-aryl-4,6-dimethoxyindoles and 2,3-disubstituted-4,6-dimethoxyindoles. The reaction of 4,6-dimethoxyindoles under Friedel-Crafts or Vilsmeier-Haack acylation gave the 2- and 7-indolyldeoxybenzoins in good yield. Cyclisation of 7-indolyldeoxybenzoins with N,N-dimethylformamide dimethyl acetal as a one carbon reagent gave the pyrroloquinolin-6-ones in high yield. Reduction of pyrroloquinolin-6-ones with hydrogen gas and 10% palladium on carbon or lithium aluminium hydride yielded the dihydropyrroloquinolin-6-ones. Demethylation of pyrroloquinolin-6-ones with 48% hydrobromic acid in glacial acetic acid gave a mixture of the monohydroxy and dihydroxy analogues in high yield. The synthesis of quinolin-4-ones using the Conrad-Limpach method was attempted using three different cyclisation conditions such as Dowtherm A, polyphosphoric acid and a mixture of diphenyl ether and methanesulfonic acid. Quinolin-2-ones such as 4-methyl-3-aryl-, 3,4-diaryl- and 3-aryl-4-benzyl-5,7-dimethoxyquinolin-2-ones could be synthesised from either the N-phenylacetylaniline or the N-trifluoroacetyl aniline strategy. Attempted reduction of the quinolin-2-ones with standard metal hydride reagents was unsuccessful. However reduction was achieved via the conversion of quinolin-2-one to the corresponding 2-chloroquinoline followed by reaction of the chloroquinoline with zinc powder and glacial acetic acid to produce a novel, highly substituted quinoline system. Demethylation was successfully carried out with 48% hydrobromic acid in glacial acetic acid to give the trihydroxyquinolin-2-one in high yield. The reactions of 4-substituted-5,7-dimethoxyquinolin-2-ones and the corresponding 2-chloroquinolines as potential organic intermediates were explored. Facile formylation of both quinolin-2-ones and 2-chloroquinolines was observed under Vilsmeier-Haack conditions while acetylation was successful under Friedel-Crafts conditions using antimony (V) pentachloride as the Lewis acid. Further reaction of 8-formyl-quinolin-2-one with 1,2-diaminobenzene in N,N-dimethylformamide led to the formation of a new 8-(benzimidazolyl)-quinolin-2-one ring system. The quinolin-2-ones exhibited selective electrophilic substitution at the C8 position for a range of reactions. However, an unexpected nitration occurred at the C3 position for the 4-methoxy and 4-phenyl-5,7-dimethoxyquinolin-2-ones with good yields. A series of novel 4,6-hydroxylindoles was successfully synthesised from the corresponding methoxy analogues in high yield using anhydrous aluminium chloride. When 3-(4-bromophenyl)-4,6-dimethoxyindole was reacted with 48% hydrobromic acid in glacial acetic acid a 2,2?-indolylindoline dimer was formed. The 5,7-dihydroxyquinolin-2-ones were similarly synthesised in high yield using anhydrous aluminium chloride in chlorobenzene.

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Burnett, Duane Arthur. "Synthesis of nitrogen containing heterocycles /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487264603219377.

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Khan, Musharraf Naveed. "Synthesis of different heterocyclic compounds of pharmaceutical relevance." Thesis, University of Huddersfield, 2013. http://eprints.hud.ac.uk/id/eprint/19503/.

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This thesis describes the synthesis of different cyclic imines and the exploration of their reactivity with cyclopropenones and 1,3-dipoles,as well as an investigation of the chemistry of the products. The synthesis of biologically and pharmaceutically important heterocyclic natural product analogues, such as the pyrroloazepines, indolizidines and pyrrolizidines has been achieved using a cycloaddition reaction between cyclic imidates and cyclopropenones. A new route to pyridines has been developed using the generation of a proposed 3-azacyclopentadienone as the key step. The 3-azacyclopentadienones are generated by using boiling toluene to induce a [2+2]-cycloreversion in a series of azabicyclo[3.2.0]hept-2-en-4- ones. Regiospecific Diels-Alder reaction of the intermediate 3-azacyclopentadienone with a styrene is followed by chelotropic extrusion of carbon monoxide and loss of hydrogen to give the pyridine. The process is similar to the well-known process by which benzenes are accessed from cyclopentadienones. The azabicyclo[3.2.0]hept-2 en-4-ones were available from the reaction of cyclopropenones with 1-azetines, where cyclopropenones behave as an all carbon 1,3- dipole equivalents. Using the same methodology 1,3-dipolar cycloaddition of nitrile oxides to 4-aryl-2-alkylthio-1-azetines afforded a series of oxadiazabicyclo[3.2.0]heptenes as single diastereoisomers. Heating these cycloadducts in toluene resulted in an overall [2+2]- cycloreversion to give 5-alkylthio-3-aryl-1,2,4 oxadiazoles. Cycloaddition reactions of a series of benzodiazepines were also studied. The benzodiazepines were formed using literature methods and converted to cyclic imines with the help of Meerwein’s reagent. Reactions between such cyclic imines and cyclopropenones and 1,3 dipoles were attempted to produce tricyclic and tetracyclic benzodiazepine analogues. Finally, some multicomponent reactions of aryl aldehydes with cyanides and 1,3-dicarbonyl compounds were investigated to produce fully substituted heterocyclic compounds like dihydropyridines and pyrans with substituents suitable for intramolecular cyclization and imine formation. The main substituent of interest was the azide group as this had been used in section 2.3.3.1.2 & 2.3.3.1.3 in this thesis.

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Stewart, Lesley Ann. "Synthesis of heterocyclic compounds as potential anticancer agents." Thesis, University of Glasgow, 1996. http://theses.gla.ac.uk/4936/.

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Taher, Abutariq. "Novel cyclisations of nitro-compounds for heterocyclic synthesis." Thesis, Loughborough University, 2001. https://dspace.lboro.ac.uk/2134/34705.

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The research described in this thesis is aimed at developing novel methods of synthesis for heterocyclic compounds, in particular cyclisation reactions involving the nitro functional group. The first chapter describes investigations into the Wallach imidazole synthesis. A number of chloroimidazoles were prepared, but the possible extension to highly functionalised imidazoles proved elusive. The second chapter describes studies on the successful conversion of nitroimidazolyl malonates 1 into imidazo[4,5-c]isoxazoles 2, Scheme 1. Related cyclisations are described in chapter three and the thiophene fused isoxazole 3 was successfully prepared. Chapter four investigates the reactivity of the strained imidazo[4,5-c]isoxazole heterocycles. Ring opening of the isoxazole occurred on reaction with phosphines to give iminophosphorane derivatives. Reactions with electron deficient acetylenes led to pyrrolyl imidazoles 4, and a novel [1,4]diazepino[2,3-c]isoxazole 5, Scheme 1, but no reaction was observed with alkenes. [Illustration omitted.] Chapter five entails synthesis of a series of 5-aryl-2H,1H-imidazo[4,5-d][1,2,3]triazole derivatives 7. Triethyl N-1-ethyl-2-methyl-4-nitro-1H-imidazol-5-yl phosphoramidate compound 6 was treated with a range of aryl isocyanates which gave imidazo[4,5-c]triazoles 7 in moderate to good yields. A mechanism involving carbodiimide formation was postulated and was supported using infra-red spectroscopy, Scheme 2. Chapter six reports a new synthesis of 5-aryl-2H indazole derivatives 9 by base catalysed reaction of 2-nitrobenzyl triphenylphosphonium bromide salts 8 with a range of aryl isocyanates. A mechanism of this reaction was proposed and investigated by infra-red spectroscopy, Scheme 3.

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Shirtcliff, Laura Donnell. "'Coarctate' cyclizations : applications to heterocycle synthesis /." view abstract or download file of text, 2006. http://proquest.umi.com/pqdweb?did=1188876631&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.

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Thesis (Ph. D.)--University of Oregon, 2006.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 336-357). Also available for download via the World Wide Web; free to University of Oregon users.

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Cai, Chunming. "Microwave mediated synthesis of nitrogen- and/or oxygen-containing compounds." [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0013762.

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Lee, On-yi. "Synthesis of heterocycles via phenylseleno group transfer radical cyclization and chemoselective reductive amination promoted by InCl3." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B3955756X.

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Trippier, Paul Charles. "Synthesis of highly substituted heterocycles : the oxazolomycins." Thesis, University of Oxford, 2006. http://ora.ox.ac.uk/objects/uuid:b758987c-7a0c-4c1b-982c-61b4d383680a.

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This thesis is concerned with studies towards the total synthesis of a class of natural products - the oxazolomycins. Attention was focused on the left-hand side triene fragment and right-hand side lactam heterocyclic system. This thesis describes the synthesis of a racemic terminal phenyl analogue of oxazolomycin A and C, possessing the left-hand side triene geometry as required. A novel truncated pyridine analogue is also described. The molecules represent a racemic total synthesis of analogues of phthoxazolin A and inthomycins B and C. The synthesis is based upon a crucial Stille cross-coupling reaction between stannane and diene iodide fragments. The stannane fragment was synthesised using literature precedented methods and the vinyl halide prepared using a highly stereoselective Wittig, Takai homologation or Stork reaction leading to a variety of ratios of mixtures of Z, E and E, E diene halides. These investigations led to the availability of 1:1, 3:1 and 1:3 mixtures of Z, Z, E : Z, E, E left hand side triene fragments possessing the required stereochemistries for oxazolomycin A and C. Utilising existing methodology developed in the Moloney group, investigations were carried out towards construction of β-keto esters possessing terminal hydroxyl functions, suitable for diastereoselective aldol ring closure. Following extensive protecting group manipulation and N-acylation coupling optimisation, a TIPS protected β-keto acid, existing as predominantly the keto tautomer, was successfully coupled to an oxazolidine heterocycle. This N-acylated oxazolidine upon Dieckmann cyclisation would present an advanced intermediate of opposite configuration (Lserine is used here as a cheaper starting material for the construction of the oxazolidine instead of D-serine) to the oxazolomycin right-hand side.

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Langgaard, Kristensen Jesper. "Metalation, halogen-metal exchange and Pd(0) catalyzed cross-coupling reactions : application to the synthesis of substituted aromatic and heteroaromatic systems /." [Cph.] : Department of Medicinal Chemistry, Royal Danish School of Pharmacy, 2001. http://www.dfh.dk/phd/defences/previous2002.htm.

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Nocanda, Xolani Wittleton. "Applications of Baylis-Idllman methodology in the synthesis of chromene derivatives." Thesis, Rhodes University, 2001. http://hdl.handle.net/10962/d1018257.

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The reaction of salicylaldehyde with various activated alkenes, viz., methyl vinyl ketone, ethyl vinyl ketone, phenyl vinyl sulfone, phenyl vinylsulfonate, acrolein and acrylonitrile, under Baylis-Hillman conditions, has been found to proceed with the chemoselective formation of chromene derivatives. The reaction conditions have been optimised and chromene derivatives have been obtained in isolated yields up to 87 %. The generality of the reaction, using 1,4-diazabicyclo[2.2.2]octane (DABCO), as the catalyst, and a heterogeneous (chloroform-water) solvent system, has been established using a range of salicylaldehyde derivatives,. including 2-hydroxynaphthaldehyde. The formation of chromene derivatives, under these conditions, has been assumed to proceed via an initial, Baylis-Hillman reaction, followed by cyclisation involving intramolecular conjugate addition, and subsequent dehydration. Evidence supporting this sequence has been obtained from the isolation ofBaylis-Hillman products from reactions involving the use of tertbutylclimethylsilyl-protected salicylaldehyde, 4-hydroxybenzaldehyde and tert-butyl acrylate as substrates. The potential of the ''Baylis-Hillman zwitterion" to participate as a donor species in Michael-type addition reactions has been explored and a series of climeric products has been isolated. The Baylis-Hillman methodology has also been successfully extended to the synthesis of sulfurcontaining heterocyclic systems, and a range of 3-substituted thiochromenes has been obtained in moderate yields, using 2,2'-dithiobenzaldehyde and various activated alkenes in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as catalyst. The electron-impact mass spectra of selected chromene and thiocbromene derivatives have been investigated permitting comparison of the fragmentation of the oxygen- and sulfur-containing analogues. In a study directed at the synthesis of potential HIV -1 protease inhibitors, chromene- and thiocbromene-containing analogues of the clinically useful drug, ritonavir, have been prepared. Thiochromene and chromene derivatives were converted to the corresponding 3 -carboxylic acids and coupled with a specially prepared, hydroxyethylene dipeptide isostere to afford ritonavir analogues containing cbromene and thiochromene termini in ca. 60% yield.

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Hussain, Amjad. "The synthesis of heterocyclic compounds related to natural products." Thesis, Swansea University, 2001. https://cronfa.swan.ac.uk/Record/cronfa43039.

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The thesis relates to the synthesis of heterocyclic compounds related to Natural Products. Chapter 1 deals with an introduction to hypervalent iodine reagents and their uses as phenolic oxidation reagents. The mechanism is also discussed. Chapter 2 concentrates on the production of 3-substituted phenols and the subsequent hypervalent iodine oxidation to see if a variety of chromenone compounds can be formed via intramolecular attack. Whilst not successful in generating the desired compounds, a number of oxidised products were isolated. Chapter 3 deals with making the 3-nucleophilic side chain on various phenols more rigid in the hope of aiding cyclisation. One reaction of note from this chapter was that an epoxide ring utilised, to give rigidity in the side chain, withstood the hypervalent iodine oxidation. Chapter 4 utilises the epoxide to bring rigidity to the 3-substituted side chain. All products bar one proved successful in generating their appropriate epoxychromenes, and that which didn't provided an alternative cyclised product. The final chapter deals with possible future work now that some success has been achieved.

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Peters, Jennifer Margaret 1956. "Synthesis and monoamine uptake inhibiting properties of perisubstituted tricyclic compounds." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/291828.

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The synthesis of 1-methyl-promazine, 4-hydroxymethyl-iminodibenzyl, and 4-bromo-5-trimethylsilyl-iminodibenzyl via dilithiation and ¹H-NMR's are described. Molecular modeling was done for the latter compound. The heat of dissociation was 30.6 kcal/mole for the lowest energy conformer. Rotational energies were examined for three bonds. The IC₅₀ values for inhibition of neurotransmitter uptake by rat brain synaptosomes were determined for a series of 1-substituted promazines, and 4-substituted imipramines. 1-Substituted promazines were fair inhibitors of serotonin uptake with an average IC₅₀ of 2000 nm. Their potency for inhibiting norepinephrine uptake was difficult to assess due to poor assay reproducibility, and the average IC₅₀ was estimated at 200 to 1700 nm. Serotonin, but not norepinephrine, uptake inhibition was increased with additional ring substitution at C(2) with a trifluoromethyl group. The 4-substituted imipramines were equal or slightly decreased in potency to unsubstituted imipramine for uptake inhibition of both neurotransmitters. IC₅₀'s were also reported for imipramine and desipramine.

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Duan, Gongping. "Design, synthesis, and photophysics and photochromic study of dithienylethene-containing heterocyclic derivatives and N-heterocyclic carbene-ruthenium (II) complexes." Click to view the E-thesis via HKUTO, 2010. http://sunzi.lib.hku.hk/hkuto/record/B44248246.

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Zinser, Caroline Magdalene. "Palladium and gold N-heterocyclic carbene complexes : synthesis and catalytic applications." Thesis, University of St Andrews, 2019. http://hdl.handle.net/10023/17066.

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Orton, Edward. "Synthesis and chemistry of 4,5-dimethylene-1,3-dioxolan-2-one and related compounds /." Thesis, Connect to this title online; UW restricted, 1985. http://hdl.handle.net/1773/8620.

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Du, Wei, and 杜玮. "Palladium-catalyzed oxidative cascade cyclizations via C-N/C-C formation for synthesis of nitrogen heterocycles." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206320.

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Illesinghe, Jayamini P. M. "Synthesis and use of nitrogen heterocycles in metal mediated reactions." Monash University, School of Chemistry, 2004. http://arrow.monash.edu.au/hdl/1959.1/9637.

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Somphol, Kittiya Chemistry Faculty of Science UNSW. "Synthesis of new heterocyclic structures based on indoles." Awarded by:University of New South Wales. Chemistry, 2007. http://handle.unsw.edu.au/1959.4/40829.

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Novel indolo-macrocycles have been generated from the attempts to synthesise bis-indolo-cyclotriveratrylenes by the condensation of I, I'-diindolyl-3,3'-dimethanols catalysed by p-toluenesulfonic acid. The addition of substituents on indoles led to enhanced solubilities of the macrocycles. Nine- and six-membered ring compounds have been synthesized from the acid-catalysed reaction of I,I'-diindolyl compounds and aryl aldehydes. Some reactions of these compounds and the attempted synthesis of 2,2' diindolylmethanes from the cyclic compounds have also been described. The electrophilic substitution reactions of 3-substituted 4,6-dimethoxyindole 2,6-dimethanols and 3-substituted 4,6-dimethoxyindole-7 and 2-carbaldehydes and I-substituted indoles afforded triindolyl dialdehydes. The wriation of substituents at C-7 of indole-7-aldehydes and at C-2 of indole-2-aldehydes has also been discussed. Reaction of the hydroxymethylindole and 1,2-di(indol-I-ylmethyl)benzene gave a new macrocycle. Substitution reactions of 2,2???-diindolylmethane-7,7'-dimethanol and indole-7- and 2-aldehydes gave tetraindolyl dialdehydes. Sodium borohydride reduction of tri- and tetra-indolyl dialdehydes gave tri- and tetra-indolyl dimethanols respectively. Acid-catalysed reactions of tri- and tetra-indolyl dimethanols afforded only calix[3] and [4]indoles respectively when all substituents at C-3 of indoles were aryl groups. New conditions for indole based imine synthesis have been established Macrocyclic imine formation from mono-, di-, tri and tetra-indolyl dialdehydes has been investigated. Reactions of indole-3, 7-dialdehydes and short chain diamines (1,2-diaminoethane, 1,2-diaminobenzene and 1,6-diaminohexane) gave mixtures while the reactions with long chain diamines (1,10 diaminodecane and 1,12-diaminododecane) gave monoindolyl macrocyclic imines. Reaction of indole-2, 7-dialdehydes and short chain diamines afforded diindolyl macrocyclic imines with head-tail structures, and the 2,7';2',2";7",2'''-Tetraindole-7 ,7"'-dialdehyde underwent cyclisation with triindolyl dialdehydes and 1,6-diaminohexane afforded triindolyl macrocyclic imines. 1,2 diaminoethane while the 2,3 ';1',1 ";3 ",2"'-tetraindole-7,7"'-dialdehydes underwent imine, with its precise structure established by X-ray crystallography. Reaction of of 1,3-di(indol-l-ylmethyl)benzene and 1,2 diaminoethane yielded a new macrocyclic reactions with long chain diamines yielded monoindolyl macrocyclic imines. Reaction ring closure with 1,2 diaminoethane and 1,6-diaminohexane.

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Rogers, James William. "1-benzotriazolyl-2-propynones as novel 1,3-biselectrophiles, benzotriazole-assisted thioacylation and synthesis of energetic materials." [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0013389.

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Allott, Keith. "The oxidative elimination and ring expansion expansions of heterocyclic nitromethyl compounds." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329598.

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Grisle, Roger Anthony. "Synthesis of novel heterocyclic difluoro monomers via the chemistry of reissert compounds." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-05042010-020216/.

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Björk, Malin. "Synthesis of sulfur and seleniumn heterocycles, including derivatives of imidazopyridine and benzimidazole /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-597-6/.

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Yuen, Yue Tai. "Trithiazyl trichloride in the synthesis of sulfur-nitrogen heterocyclic compounds." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362732.

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Roxburgh, C. J. "The synthesis of heterocyclic compounds from Indan-1, 3-diones." Thesis, University of Portsmouth, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234430.

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ABSTRACT 2-Phenyl-indan-1,3-dione reacts via a Michael addition with 2-vinylpyridine to yield 2-phenyl-2-(2-(2-pyridyl) ethyl) indan- 1,3-dione, which on catalytic hydrogenation of the pyridine ring yields, via a ring cyclization/expansion reaction, rel(12S,14aR) 12- phenyl-1~3,4,12,13,14,l4a-octahydropyrido[l,2-£] [2]benzazonin- 6,ll-dione. A lithium aluminium hydride reduction of rel(12S,14aR) 12- phenyl-l,2,3,4,12,l3,14,14a-octahydropyrido[l,2-£] [2]benzazonin- 6,ll-dione yielded rel(llS,12S,l4aR) ll-hydroxy l2-phenyl-substituted derivative as the only isomer~ Various derivatives of this system including the 12-phenyl-ll-keto compound were synthesised and the stereochemistry of these established in each case. Treatment of rel(11S,12S,14aR)12-phenyl-l,2,3,4,6,11,12,13,14,14a-decahydropyridoTl, 2~b] [2]benzazonin-l1-ol with tosylchloride yielded the spiro quaternary nitrogen compound rel(4aR,7S,7aR,13S) 1,2,3,4,4a,S, 6,7,7a,12-decahydro-7-phenylisoindolo[l~2-~]quinoliZin-13-ium tosylate via transannular displacement of the I1-tosyl group. Treatment of this with lithium aluminium hydride uncovered a novel ring expansion to rel(SS,6R,10R,13S)5,6,7,8,9,10,11,12,13,14- decahydro-13-phenyl-S,6~10~nitrilobenzocyclododecene. Treatment of rel(11~,12~,14aR) 12-phenyl-l,2,3,4,6,11,12,13,- 14,14a-decahydropyrido[l,2-b) [2)benzazonin-l1-ol with phosphorus oxychloride in pyridine yielded two compounds, rel(4aR,7S,7aR,13S) 1,2,3,4,4a,S,6,7,7a,12-decahydro-7-phenylisoindolo[1,2-d]quinolizin- 13-ium phosphate via a transannular reaction and rel(11K,12R,14aR)- 12-phenyl-l,2,3,4,6,11,12,13,14,l4a-decahydropyrido[1, 2-Q) [2]benzazonin- ll-ol with a change in piperidine/benzazonine ring fusion stereochemistry. 2-Phenyl-2-(2-(1,2,3,4-tetrahydroquinolin-2-yl)ethyl)indanl, 3-dione did not undergo the ring closure/expansion sequence and attempts to prepare 2-phenyl-2-(2-(S-ethyl-2-piperidyl)ethyl)indanl, 3-dione and 2-methyl-2-(2-(2-piperidyl) ethyl) indan-l,3-dione to investigate a similar reaction were thwarted by non-selective reduction. Hydrazinolysis of 2-phenyl-2-(3-~-phthalimido)indan-l,3-dione gave 1,2,3,4-tetrahydro-l0b-hydroxy-l-phenylpyrido[2,1-~)isoindol- 6(4li)-one as the major product. A lithium aluminium hydride reduction of this gave rel(lR,lObR) I-phenylbenzo[a]isoindole. 2-p-Methoxyphenyl-2-(2-(2-piperidyl)ethyl)indan-l,3-dione did not undergo the ring cyclization/expansion reaction to a ninemembered ring but 2-p-chlorophenyl-2-(2-(2-piperidyl)ethyl)indan- 1,3-dione gave rel(12~,14aR)12-p-chlorophenyl-l,2,3,4,l2,l3,14,14aoctahydropyrido[ 1,2-Q) [2]benzazonine-6,11-dione. Lithium aluminium hydride reduction of this gave rel(ll~,12~,14aB) and rel(llR,l2~,- 14aR) 12-p-chlorophenyl-l,2,3,4,6,ll,l2,13,l4,l4a-decahydropyrido[ l,2-QJ (2)benzazonin-ll-ol in equal amounts. A variety of analogues of the above systems were prepared to test the generality of the ring closure/expansion sequence. None of these gave the required products showing the necessity of the basic 2-phenyl-indan-l,3-dione unit for successful reaction

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30

Abid, Huda Ahmed. "Investigations into the synthesis of heterocyclic compounds with biological applications." Thesis, Keele University, 2018. http://eprints.keele.ac.uk/5438/.

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There is a growing body of literature that recognises the importance of tandem reactions, where a number of transformations are carried out in a one-pot process. Such reactions offer considerable benefits such as: a reduction in time, and the sequence of synthetic processes that subsequently improve in efficiency. Particularly useful is the one-pot cascade of transforming alcohols to alkenes using an Oxidation-Wittig sequence. Although, the Wittig reaction is a dominant and powerful olefination method, sometimes the isolation of, instability of, toxicity of, or volatility of the carbonyl compounds that are applied in a Wittig reaction is limiting. However, a tandem oxidation processes (TOP) in the presence of a number of oxidants can be employed to overcome these shortcomings. Herein, a variety of starting materials were used to construct six and five membered rings that possibly could be annulated later. Chapter 2 describes the attempted development of novel methodology for the construction of carbon-carbon bonds from diols in two routes. Firstly, a domino oxidation-Wittig olefination reaction was attempted to convert diols into extended alkene products through reacting with different ylides. The electrocyclisation of those alkenes (trienes) has been examined using thermal and microwave irradiation. In the second route, work on the intramolecular annulation of alkenes via 6π-electrocyclisation and then oxidation is described. No ring closure was observed under thermal or photochemical promotion of the 6π-electrocyclisation. The attempted application of acid-catalysed Nazarov reaction of divinyl ketones and TOP reaction of diol is described in Chapter 3 using divinyl ketone 302 and dihydroxyacetone 294 as key intermediates but only limited success was achieved. The Nazarov cyclisation could not be promoted on the TOP derivatives obtained. Chapter 4 explores the development of tandem oxidation/Diels-Alder reactions through potential inter- or intra-molecular Diels-Alder reactions. Firstly, two alcohols were used for the synthesis allyl and homo allyl esters via TOP reaction of cinnamyl alcohol and cyclohexenmethanol. Secondly, six vicinal diols and diketones were examined under the same conditions to synthesise dienes that might act as dienophiles. Unfortunately, no success was achieved. The final chapter, describes the successful preparation, via Pictet-Spengler cyclisation, and evaluation of a number of novel 1,2,3,4-tetrahydro-β-carbolines that have anti-malarial activity. Although active, the compounds prepared did not show any significant increase in the growth inhibitory activity of compared to the existing collections, but they did successfully confirm the SAR model proposed.

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31

Hunter, Gordon A. "Synthesis and properties of 3-hydroxypyrroles, 3-hydroxythiophenes, and related compounds." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/15064.

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32

Shukla, Rajesh 1964. "Experimental and Theoretical Studies of Polycarbocyclic Compounds." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc279238/.

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Part I. Diels-Alder cycloadditions of 1,2,3,4,9,9-hexachloro-1α,4α,4aα,8aβ-tetrahydro-l,4-methanonaphthalene (32) and 1,2,3,4,9,9-hexachloro-lα,4α,6,7- tetrahydro-l,4-methanonaphthalene (33) to 4-methyl- and 4-phenyl-l,2,4-triazoline-3,5-dione [MTAD and PTAD, respectively] and to N-methylmaleimide (NMM) have been studied. The structures of several of the resulting cycloadducts were determined by X-ray crystallographic methods. The observed stereoselectivity of each of these Diels-Alder reactions was further investigated via application of theoretical methods. Thus, semiempirical (AMI) and ab initio molecular orbital calculations were used to calculate relative energies. Ab initio calculations were employed to perform frontier molecular orbital analyses of diene-dienophile interactions.

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33

Duan, Gongping, and 段公平. "Design, synthesis, and photophysics and photochromic study of dithienylethene-containing heterocyclic derivatives and N-heterocycliccarbene-ruthenium (II) complexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44248246.

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34

Kimball, David Brian. "(Alkynylphenyl)triazenes and phenylacetylene macrocycles for the synthesis of heterocycles and aromaticity probes /." view abstract or download file of text, 2002. http://wwwlib.umi.com/cr/uoregon/fullcit?p3055694.

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Thesis (Ph. D.)--University of Oregon, 2002.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 249-278). Also available for download via the World Wide Web; free to University of Oregon users.

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35

Hung, Faan-fung, and 孔繁峰. "Luminescent platinum(II), palladium(II) and gold(III) complexes containing isocyanide, alkynyl and N-heterocyclic carbene ligands : synthesis, photophysical properties and material applications." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206318.

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36

Zhou, Jiamin, and University of Lethbridge Faculty of Arts and Science. "Synthesis of 1-chloro-1,2,4,6-selenatriazines and some products of reduction." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2005, 2005. http://hdl.handle.net/10133/295.

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A general route to 1-chloro-1,2,4,6-selenatriazines with substuents on 3,5 positions has been developed by the reactions of N-imidoylamidines with selenium tetrachloride. The mechanism for these reactions is discussed according to the observed intermediates. At least two intermediates exist. One of the intermediates, 1,1-dichloro-3-trichloromethyl-4H-5-diisopropylphenyl-1,2,4,6-selenatriazine, was identified by 1HNMR, Mass spectroscopy and X-ray crystallography. 1-Chloro-1,2,4,6-selenatriazines were synthesized in high yield and fully characterized. Five 1-chloro-1,2,4,6-selenatriazine crystal structures were obtained. Reduction of 1-chloro-1,2,4,6-selenatriazines with triphenylamtimony immediately produced the corresponding selenatriazinyl radicals in hot acetonitrile. Pure radicals were obtained by in-situ crystallization as their dimers from reaction. Two crystal structures were obtained for 3-trifluoromethyl-5-p-tolyl-1,2,4,6-selenatriazinyl dimer and 3-trifluoromethyl-5-p-methyloxyphenyl-1,2,4,6-selenatriazinyl dimer. EPR spectroscopy measured all radicals coupling to three unique nitrogen atoms with 7 broad lines. There is no resolvable hyperfine coupling to 77Se, 37Cl/19F and phenyl protons.
xv, 172 leaves : ill. ; 29 cm.

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37

Kleinhans, Dewald Johannes. "Studies in the synthesis of benzoxazole compounds." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97900.

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Thesis (PhD)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Benzoxazoles are an important class of π-electron-excessive, benzene-fused heterocyclic compounds found in natural products and display a wide range of pharmacological applications. It is therefore a widely used starting scaffold for drug and agrochemical discovery programs. Other applications include: chiral auxiliaries in asymmetric reactions, chiral receptors for the resolution of racemic mixtures, fluorescent whitening dyes, various photochromic materials and as ligands for a wide range of catalytic reactions. Due to our interests in resorcinarenes, we came across 4-hydroxybenzoxazoles, a structural motif that has not been explored as potential asymmetric ligands. In this thesis it was attempted to investigate the synthesis, functionalisation and coordination chemistry of these compound class and finally look at a method of synthesising chiral 4-hydroxybenzoxazoles from amino acids. A small library of achiral 4-hydroxybenzoxazoles were synthesised in good yields. These compounds were then reacted with various transition metals, of which only the Pd-salts proved to return any usable compounds. The first structural evidence of the bonding of 4- hydroxybenzoxazoles was recorded from single crystal X-ray diffraction analysis of the coordination compounds that formed. Different coordination modes were recorded, depending on the ligand and the Pd-salt used. The PdCl2 compounds were also tested for catalytic activity with a Heck reaction, showing good conversions for the reaction between iodobenzene and styrene to form stilbene. Further examination pointed to the ligands playing an insignificant role in the reaction and the products possibly due to only the PdCl2’s reactivity. During this period it was also attempted to functionalise the phenol group with P(III) groups and repeat the coordination and catalytic studies. Efforts to synthesise these compounds were not successful, with oxidation of the P(III) to P(V) groups or degradation of these compounds. Efforts to synthesise these via phosphorous protection, utilising BH3 or the in situ trapping of the compounds with transition metals, were also not successful. During the trapping experiments the phosphinite and Pd-salt formed a re-arranged product that is a known and useful catalyst on its own. Finally a small library of chiral benzoxazoles and 4-hydroxybenzoxazoles were synthesised, starting from amino acids and utilising a Mitsunobu reaction to perform the ring closing. Antimicrobial tests with these compounds did not return any appreciable results.
AFRIKAANSE OPSOMMING: Bensoksasool is 'n belangrike klas van π-elektron-ryk, benseen-saamgesmelte heterosikliese verbindings wat in natuurlike produkte voorkom en 'n wye verskeidenheid van farmakologiese funksies vertoon. Dit is dus 'n baie algemene basis struktuur vir dwelm- en landbouchemiese ontdekkings programme. Ander gebruike sluit in: chirale ligande in asimmetriese reaksies, chirale reseptore vir die resolusie van rasemiese mengsels, fluoresserende verwittings kleurstowwe, verskeie fotochromiese materiaal en as ligande vir 'n wye verskeidenheid van katalitiese reaksies. As gevolg van ons belangstelling in resorsinarene, het ons op 'n strukturele motief afgekom wat nog nie ondersoek is as potensiële asimmetriese ligande nie, die 4- hidroksiebensoksasole. In hierdie tesis is gepoog om die sintese, funksionalisering en koördinasie chemie van hierdie klas verbindings te ondersoek en uiteindelik 'n metode te ontwikkel om die sintese van chirale 4-hidroksiebensoksasole vanaf aminosure te bewerkstellig. 'n Klein biblioteek van achirale 4-hidroksiebensoksasole was gesintetiseer in goeie opbrengste. Hierdie verbindings was toe behandel met verskeie oorgangsmetale, waarvan slegs die Pdsoute enige bruikbare verbindings gevorm het. Die eerste strukturele bewyse van die binding van die 4-hidroksiebensoksasole is aangeteken met behulp van enkelkristal X-straaldiffraksie ontleding van die koördinasieverbindings wat gevorm is. Verskillende koördinasie mode is aangeteken, afhangende van die ligand en die Pd-sout wat gebruik was. Die PdCl2 verbindings is ook vir katalitiese aktiwiteit met 'n Heck reaksie getoets. Die reaksie het baie goeie omskakeling gewys vir die reaksie tussen iodobenseen en stireen na stilbeen. Verdere ondersoeke het getoon dat die ligande nie ‘n beduidende rol in die reaksie speel nie en die produkte moontlik slegs as gevolg van die PdCl2 se reaktiwiteit is. Gedurende hierdie tydperk was daar ook probeer om die fenol groep met P(III) groepe te funksionaliseer. Met die uitgangstowwe sou die koördinering en katalitiese studies herhaal word. Pogings om hierdie verbindings te sintetiseer was nie suksesvol nie, met oksidasie van die P(III) na P(V) groepe of afbreking van hierdie verbindings. Pogings om dit te sintetiseer via fosfor beskermingstegnieke, deur gebruik te maak van BH3 of die in situ vasvang van die verbindings met oorgangsmetale, was ook nie suksesvol nie. Gedurende die vasvang eksperimente het die fosfien en PdCl2 ‘n herrangskikkings-produk gevorm wat op sy eie ‘n bekende en nuttige katalisator is. Ten slotte was 'n klein biblioteek van chirale bensoksasole en 4-hidroksiebensoksasole gesintetiseer, vanaf aminosure. Om die ringsluiting te bewerkstellig was ‘n Mitsunobu reaksie gebruik. Antimikrobiese toetse met hierdie verbindings het nie enige noemenswaardige resultate opgelewer nie.

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38

McErlean, Christopher Stephen Paschal. "Synthesis and biosynthesis of some naturally occuring oxygen heterocycles /." [St. Lucia, Qld.], 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17082.pdf.

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39

Guilani, Bardia. "Synthesis of novel heterocyclic polymers via the chemistry of Reissert compounds." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42072.

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The chemistry of a well established class of compounds, known as Reissert compounds, was used to prepare several novel N-heterocyclic polymers. Initially, alkylation of quinoline Reissert compounds was closely examined to test the feasibility of the use of such compounds as difunctional monomers. An A-B and an A-A monomer were then prepared by the reaction of quinoline with p-formylbenzoyl chloride and isophthaloyl chloride, respectively. The former monomer could be polymerized interfacially to afford a low molecular weight polyester exhibiting Tg of 190Â°C.

Several novel bis-isoquinolines were prepared using an en amine reaction reported by Minter and Re.52 One of these bis-isoquinolines was used to prepare two novel bis-Reissert compounds which could be polymerized with several dialdehydes to obtain high molecular weight N-heterocyclic polyesters. Cleavage of the ester groups afforded a novel N-heterocyclic polyalcohol. It was observed that circumvention of a rearrangement reaction particular to Reissert compounds by molecular design led to the synthesis of N-heterocyclic polyesters that had the highest molecular weights and intrinsic viscosities.

A novel N-heterocyclic difluorodiketone was prepared in four steps using the enamine reaction of Minter and Re52 and Reissert compound chemistry. The diketone was polymerized via standard techniques 72 to afford several novel poly(N-heteroaryl-ether-ketones) with high glass transition temperatures and thermal stabilities. Thus, polymerization of 1,4-bis(4-fluorobenzoyl)isoquinoline with biphenol yielded a poly(ether-ketone) with an intrinsic viscosity of 0.34 dl/g. This polymer showed Tg at 209Â°C and was stable up to 500Â°C in air.

Master of Science

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40

Zhong, Cheng. "Amine promoted asymmetric cascade synthesis of highly functionalized heterocycles." Morgantown, W. Va. : [West Virginia University Libraries], 2010. http://hdl.handle.net/10450/10986.

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Thesis (Ph. D.)--West Virginia University, 2010.
Title from document title page. Document formatted into pages; contains xvi, 498 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 75-82).

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41

Moragas, Solà Antoni. "Synthesis and use of highly substituted aziridine 2-carboxylates." Thesis, University of Nottingham, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.594593.

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42

Shawcross, Andrew Paul. "The synthesis of novel heterocyclic compounds and observations on the Vilsmeier reaction." Thesis, University of Newcastle Upon Tyne, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328112.

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43

Santoro, Orlando. "Copper(I)-N-heterocyclic carbene (NHC) complexes : synthesis, characterisation and applications in synthesis and catalysis." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/8409.

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The work described herein focuses on the synthesis and characterisation of copper(I) complexes bearing N-heterocyclic carbene (NHC) ligands, their use in catalysis as well as organometallic synthesis and related reaction mechanisms. Two classes of complexes were considered: neutral NHC-Cu(I) species and their cationic analogues. Concerning the former, initial efforts were focused on the development of a general and straightforward synthetic methodology towards complexes of the type [Cu(X)(NHC)] (X = Cl, Br, I). More than 10 NHC-Cu(I) species were synthesised in high yields under mild conditions, in air and using technical grade solvents. These complexes exhibited interesting activity in the catalytic dehydrogenation of formic acid/amine adducts proving in three times more efficiency than the copper salts previously employed in such a reaction. Hydroxide- and tert-butoxide analogues showed to be efficient catalysts in the N-methylation of amines with CO₂ as carbon source, and in the dehydrogenative coupling of silanes and carboxylic acids. Experimental and computational work were carried out in order to elucidate the mechanism of these transformations. Regarding the use of these species in organometallic synthesis, homo- and heteroleptic bis-NHC-Cu(I) complexes were employed as carbene transfer reagents to other transition metals. Aside from well-known cationic gold(I) species, two novel palladium(II) analogues were isolated and fully characterised.

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44

陳淑妤 and Suk-yu Florence Chan. "Novel synthesis and chemistry of 1, 4, 2-dithiazolium salts." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1988. http://hub.hku.hk/bib/B30426352.

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45

Lizano, Gispert Enric. "Design and synthesis of heterocyclic compounds potentially antitumor by enzymatic inhibition." Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/671158.

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This doctoral thesis is focused on the investigation and development of new compounds directed to different cancer and tropical diseases targets. Drug resistance, as well in cancer as in tropical diseases, is a hurdle which in the latest years it is driving the scientific community to investigate in new diagnostic techniques, to improve in genomic sequencing, as well as to develop new treatments through the synthesis of new small molecules, for example. The physiologic framework, that drives to resistance, is complex and for this reason, personalized treatments is an increasing concept and needed in order to improve the prognostic of the patients. Therefore, we are looking for compounds acting on multiple targets, with selectivity to diminish the adverse effects and increase the treatments efficacy. Two different synthetic routes have been carried out: the first, taking as a main nucleus the 1- spiro[benzodioxole-2,4’-piperidine], from which a wide variety of derivatives was obtained. The second route is the preparation of pirrolo[2,3-b]pyrazine derivatives, then obtaining a purine and pyrimidine analogues. All compounds were developed through classical chemistry reactions, purified by means of separation techniques (chromatography), and their structural elucidation was accomplished for every one of them. In order to test the compounds in different therapeutical targets, Eli Lilly laboratories have undertaken a high throughput screening in several targets related with cancer, tropical diseases, diabetes, amongst others. In addition, quantitative biological assays have been made to characterize aGPCRs, the receptors involved in different disorders such as cancer or cardiovascular diseases, providing information needed for their crystallization and their study as a new targets.
La present tesi doctoral està enfocada a la investigació i desenvolupament de nous compostos dirigits a diferents dianes implicades en el càncer i en malalties tropicals. La resistència al tractament, tant en càncer com en malalties tropicals, és una barrera que en els últims anys està portant a la comunitat científica a investigar noves tècniques de diagnòstic, a millorar en la seqüenciació genòmica, així com en el desenvolupament de nous tractaments com la síntesis de noves petites molècules per exemple. L’entramat dels processos fisiològics que condueixen a la resistència als fàrmacs i/o a la radioteràpia és complexa i per aquets motiu la personalització dels tractaments és un concepte creixent i necessari per millorar el pronòstic dels pacients. Per tant, es busca la síntesis de compostos que actuïn sobre més d’una diana i amb selectivitat per disminuir els efectes adversos i augmentar l’eficàcia del tractament. D’aquesta manera, s’han posat a punt dues rutes sintètiques diferents: la primera, agafant com a nucli principal l’1-espiro[benzodioxole-2,4’-piperidina], a partir del qual s’obté una gran varietat de compostos. La segona ruta, la preparació de derivats de pirrolo[2,3-b]pirazines, obtenint així anàlegs de purines i pirimidines. Aquests compostos s’han desenvolupat mitjançant reaccions clàssiques de la química orgànica, han estat purificats mitjançant tècniques de separació (cromatografia) i s’ha dut a terme l’elucidació estructural corresponent per a cadascun d’ells. Amb la finalitat d’avaluar els compostos en diferents dianes terapèutiques, els laboratoris Eli Lilly han dut a terme un cribratge d’elevat rendiment en múltiples dianes implicades en càncer, malalties tropicals, diabetis, entre d’altres. A més, s’han realitzat assajos biològics quantitatius per tal de caracteritzar els aGPCRs, receptors involucrats en diferents desordres com el càncer i malalties cardiovasculars, aportant informació necessària per a la seva cristal·lització i poder estudiar-los com a noves dianes.

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46

Chowdhury, M. L. A. "Oxidation of peptides : synthesis of heterocyclic compounds related to the penicillins." Thesis, Oxford Brookes University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370498.

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47

Ella-Menye, Jean-Rene. "Synthesis of Novel Chiral Heterocyclic Compounds for Antibacterial Agents and Peptidomimetics." ScholarWorks@UNO, 2007. http://scholarworks.uno.edu/td/611.

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Small chiral molecules are very important building blocks in the synthesis of biologically active compounds. These building blocks include nitrogen and oxygen-containing heterocycles such as 2-oxazolidinones, 1,3-oxazinan-2-ones, 2-oxazolines, oxazines, morpholine and morpholinones. Because of their interesting properties, chiral heterocycles have stirred great interest in the synthetic chemist community to develop useful and efficient strategies to these molecules. In this dissertation, the design and syntheses of various heterocyclic building blocks are presented, as well as the testing of their biological activities as antibacterial. Another very interesting family of heterocycle-containing molecules are the Aeruginosins. They are a family of marine natural products isolated from a blue-green algae, which display inhibitory activity against serine proteases such as thrombin, trypsin, and factor VIIa. Most aeruginosins contain an heterocyclic moiety called the 2-carboxy-6-hydroxyoctahydroindole (Choi) ring; this Choi moiety is a rigid bicyclic unnatural amino acid and is the core structure in the aeruginosins, indispensable to their biological activity. A synthesis of a ring-oxygenated variant of the Choi from D-mannose is reported in this dissertation. The ring-oxygenated variant of 2-carboxy-6-hydroxyoctahydroindole can potentially be used as a surrogate of Choi in the design and synthesis of aeruginosin-based thrombin inhibitors.

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48

Portela-Cubillo, Fernando. "Oxime derivatives : versatile reagents for radical-mediated syntheses of heterocycles." Thesis, St Andrews, 2009. http://hdl.handle.net/10023/856.

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49

Nguyen, René-Viet 1981. "Catalytic tandem nucleophilic addition for the synthesis of heterocycles." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115708.

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Classical methodologies for carbon-carbon bond formation often require stoichiometric amount of reagent to prefunctionalize a C-H bond. Such methods generate a lot of waste and are therefore not atom-efficient. On the other hand, the use of catalysts for the direct use of C-H bond without prior functionalization is a more desirable approach for carbon-carbon formation. For example, an overall addition reaction is 100% atom economical. This thesis focuses on the catalytic addition of the three types of C-H bonds (Csp-H, Csp2-H and Csp3-H) to unsaturated molecules such as conjugated dienes, imines and carbon dioxide to form heterocycles.
The first chapter describes the direct single addition of 1,3-diketones (Csp3- H bond) to conjugated dienes and enol ethers catalyzed by gold(III) chloride and silver(I) trifluoromethanesulfonate. The reaction is highly regioselective, although the overall yields are modest (up to 70%) due to the oxidative nature of the catalysts. Under certain conditions, the addition product undergoes a subsequent cyclization to form dihydrofurans. This tandem addition/cyclization reaction is catalyzed by trifluoromethanesulfonic acid and is discussed in the second part of the chapter.
The second chapter deals with the addition of phenol derivatives (C sp2-H bond) to conjugated dienes catalyzed by gold(III) chloride and silver(I) trifluoromethanesulfonate. The reaction affords dihydrobenzofurans via an intramolecular O-H cyclization. Investigation into the sequence of the reaction shows that the C-C bond is formed before the C-O bond.
The third chapter presents the addition of terminal alkynes (Csp-H bond) to imines catalyzed by cheap copper(I) iodide salt via a three-component coupling of salicylaldehyde derivatives, secondary amines and alkynes. Microwave irradiation is used which considerably shortens the reaction time and eliminate the use of solvents. Dihydrobenzofurans with an exocylic double bond are formed via an intramolecular O-H cyclization. The use of aliphatic alkynes molecules containing a heteroatom is critical to the success of the reaction.
Finally, in the last chapter, the addition of terminal alkynes (C sp-H bond) to carbon dioxide (catalyzed by gold(I) chlorotriphenylphosphine and silver trifluoromethanesulfonate) is applied to the synthesis of arynaphthalene lactones via a multicomponent coupling of phenylacetylene, CO2 and 3-bromo-1-phenyl-1-propyne.

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Lombard, M. J. "Aspects of the use of N-O heterocyclic compounds in organic synthesis." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370281.

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Dissertations / Theses on the topic 'Heterocyclic compounds – Synthesis'

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