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1
Qu, Wenchao. "SYNTHESIS OF FUNCTIONALIZED MACROCYCLIC POLYTHIAETHERS." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1137687463.
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Smith, Richard John Alan. "The synthesis of macrocyclic receptor compounds." Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328435.
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Lermer, Leonard. "Synthesis and reactivity of macrocyclic lactams and dynamic NMR studies of macrocyclic amines and a macrocyclic ketone." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0023/NQ38926.pdf.
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Atkins, Andrew J. "Studies on transition metal macrocyclic complexes." Thesis, University of Edinburgh, 1993. http://hdl.handle.net/1842/11664.
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Bukhari, Abeer. "Towards the synthesis of new macrocyclic receptors." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/towards-the-synthesis-of-new-macrocyclic-receptors(0bf6fd45-d433-4057-a77a-3dd4e93259ac).html.
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Iron plays a fundamental role in the regulation of chemical processes within biological systems and the control of intracellular iron concentration has important consequences in the aetiology of a variety of disease states (e.g. neurodegenerative disorders). In this thesis, which is concerned with the identification of new macrocyclic receptors, the synthesis of (N,N',N''-((3S,7S,11S)-2,6,10-trioxo-1,5,9-trioxacyclododecane-3,7,11-triyl)tris(2,3-dihydroxybenzenesulfonamide), a mimic to the natural siderophore enterochelin, is reported. Two synthetic routes to the preparation of this macrocycle are presented where a sulfonamide residue is attached to a functionalised lactone core. The title compound was prepared either via the cyclotrimerzation of methyl N-((2,3-dimethoxyphenyl)sulfonyl)-L-serinate (âpre-functionalizationâ method) or by the elaboration of a preformed macrocyclic scaffold, (3S,7S,11S)-2,6,10-trioxo-1,5,9-trioxacyclododecane-3,7,11-triaminium chloride, with 2,3-dimethoxybenzenesulfonyl chloride (âpost-functionalizationâ method). Late-stage demethylation of the macrocyle formed in these reactions - N,Nâ,Nââ-((3S,7S,11S)-2,6,10-trioxo-1,5,9-trioxacyclododecane-3,7,11-triyl)tris(2,3-dimethoxybenzenesulfonamide) using BBr3 afforded the desired enterochelin analogue. These studies indicated that the âpost-functionalisationâ protocol afforded higher yields of the desired macrocycle in a process which was not marred by the concomitant formation of sulphonamide by-products. During the synthesis of 2,3-diacetoxy-5,6-dimethylsulfonyl chloride, a key intermediate for the assembly of functionalised sulphonamide siderophores, an ortho-quinone intermediate was found to undergo an intermolecular Diels-Alder reaction from which both the keto- ((1S*,4S*,4aR*,8aS*)-2,3,8,8a-tetramethyl-1,4,4a,8a-tetrahydro-1,4-ethanonaphthalene-5,6,9,10-tetraone) and enol- ((1S*,4R*,8aS*)-5-hydroxy-2,3,8,8a-tetramethyl-1,8a-dihydro-1,4-ethanonaphthalene-6,9,10(4H)-trione) tautomeric forms could be isolated and fully characterised by X-ray crystallography thereby constituting a rare example of desmotropy.
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Goodwin-Tindall, Jake. "Synthesis of the macrocyclic core of (-)-rhizopodin." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648323.
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White, Marcus James. "Synthesis and reactions of macrocyclic thiazolium salts." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621429.
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Roka, Eszter. "Biocompatibility evaluation and synthesis of macrocyclic compounds." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1027/document.
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La faible solubilité de certains médicaments cause des problèmes majeurs dans les formulations pharmaceutiques, puisque la solubilité dans l'eau est un critère indispensable pour la biodisponibilité. Les composés macrocycliques tels que les CDs et les calixarènes ont une cavité relativement hydrophobe, leur permettant ainsi d'encapsuler de nombreuses molécules. Les CDs ont déjà été utilisées comme excipients pharmaceutiques pour l'amélioration de la solubilité. La structure de ces macrocycles permet d'effectuer de nombreuses modifications, qui causent des changements tant au niveau de leurs caractéristiques physico-chimiques que sur leurs effets sur les organismes vivants. Ainsi, l'évaluation de la biocompatibilité de ces dérivés est primordiale en vue de leur utilisation en pharmacie. Puisque l'étude de la biocompatibilité de plusieurs dérivés de β-CD a déjà été étudiée, l'objectif de cette recherche était d'étendre ces expériences à des dérivés de l'α-CD qui sont disponibles dans le commerce. Nous nous sommes intéressés aux relations entre structure et toxicité. Ainsi les dérivés alkyl éther d'α-CD, avec des chaînes alkyle de longueur croissante et substitués sur différentes positions, ont été synthétisés et leur toxicité étudiée. Les para-sulphonato-calix[n]-arènes quant à eux, ont souvent été étudiés et ont montré une forte capacité à complexer de nombreux médicaments. Ils ont aussi démontré une activité biologique polyvalente. Néanmoins, leurs effets sur le mécanisme de transport paracellulaire n'a jamais été évaluée. Les tests de viabilité cellulaire et d'hémolyse nous ont permis d'une part de classer les α-CDs et de choisir les dérivés les plus sûrs, et d'autre part de comparer leur effets toxiques dans des systèmes différents. La comparaison des α- et ß-CDs portant les mêmes modifications chimiques nous a montré l'importance du nombre d'unités de construction. Le rapport entre l'effet cytotoxique et le nombre de groupes hydroxyles libres est également très important. Les dérivés portant de longues chaînes alkyles possèdent une faible solubilité, ce qui nous a conduits vers d'autres modifications chimiques : la sulfonation de ces derniers dérivés semble avoir un impact bénéfique sur la biocompatibilité de CDs. Elle a aussi amélioré la solubilité des calixarènes. Les calix[4] et [8]arène sulphonates ont prouvé leur effet positif sur l'absorption paracellulaire, tandis que le calix[6]arène sulphonate n'a pas eu d'effet similaire. Notre recherche conclut que les changements structurels sur les anneaux macrocycliques peuvent avoir un impact majeur sur la biocompatibilité. Comme les possibilités de modification sont pratiquement illimitées, l'évaluation de la structure et de l'activité est indispensable pour faciliter les choix les plus sûrs dans les applications pharmaceutiques à venirThe low solubility of drug candidates cause a major problem in pharmaceutical formulations, as the aqueous solubility is an indispensable criterion for appropriate bioavailability. Macrocyclic compounds possess a relatively hydrophobic cavity, which is suitable for guest molecule inclusion. Cyclodextrins and calixarenes are widely studied organic host-compounds, and CDs have already been used as pharmaceutical excipients for solubility enhancement. The macrocycles’ chemical structure allows their versatile modification, which eventuates changes not only in physicochemical characteristics, but in their effects on living organisms, as well. Thus, the biocompatibility evaluation of the derivatives is fundamental. Owing to the already performed assessment of numerous β-CD derivatives’ biocompatibility, the aim of this research was to extend these experiments to commercially available α-CDs. They have been used less frequently, however several derivatives, which have not been tested yet in vitro, have the possibility of future pharmaceutical use. Their importance is also certified by their benefits in nanoparticle formation. We have been interested in concrete structure-toxicity correlations, thus alkyl ether α-CD derivatives were synthetized bearing increasing length alkyl chains, in different positions. Para-sulphonato-calix[n]-arenes have already been widely examined due to their efficient drug complexation and versatile biological activity, however, their effects on paracellular transport mechanism have not been evaluated until now.The cell viability and hemolysis tests have allowed us to rank the α-CDs and to choose the safest derivatives, also to compare their toxic effects in different systems. The comparison of α- and β-CDs bearing the same chemical modifications highlighted the importance of the number of building units. Important information has been evaluated regarding the connection between the cytotoxic effect and the number of free hydroxyl groups. Derivatives with long alkyl chains possess low solubility, which led us towards further chemical modifications. Sulfonation seemed to have beneficial impact on the biocompatibility. Sulfonation also improved the solubility of calixarenes. C4S and C8S proved their positive effect on paracellular absorption in a non-toxic concentration range, however C6S had no similar effect, thus their behaviour in in vitro absorption model system arose forward-looking questions.Our research concludes, that the structural changes on the macrocyclic rings may have major impact on the biocompatibility. As the modification possibilities are practically unlimited, the evaluation of structure and activity cannot be avoided, facilitating the safest choice for further pharmaceutical use
A gyógyszerhatóanyagok rossz vízoldékonysága nagy kihívást jelent formulálásuk során, ugyanis a vízoldékonyság elengedhetetlen feltétele a megfelelő biohasznosulásnak. A makrociklusos vegyületek belső ürege viszonylag hidrofób, ez alkalmassá teszi őket vendégmolekulákkal való komplexképzésre. A ciklodextrinek és kalixarének széles körben tanulmányozott vegyületek, egyes CD-ek bejegyzett oldékonyságnövelő segédanyagok. A makrociklusok felépítése számos kémiai módosításra ad lehetőséget, amelyek nem csupán a fiziko-kémiai tulajdonságok változását eredményezik, hanem az élő organizmusokra kifejtett hatásokat is módosítják. Ezen származékok biokompatibilitás vizsgálata tehát elengedhetetlen. Számos β-CD származék biokompatibilitása ismert már, így kutatásunk célul tűzte ki ezen vizsgálatok α-CD-ekre történő kiterjesztését. Az α-CD-ek alkalmazása ritkább, azonban vannak származékok, amelyek in vitro vizsgálata még nem történt meg, de jelentőségük a nanopartikulum-képzésben már igazolt. A szerkezet-toxicitás összefüggések feltárása érdekében olyan alkil-éter CD származékokat szintetizáltunk, amelyek növekvő szénatomszámú alkil-csoportokkal rendelkeznek, eltérő pozíciókban. A para-szulfonáto-kalix[n]aréneket hatóanyag-komplexáló tulajdonságuk, valamint sokoldalú biológiai aktivitásuk miatt széles körben tanulmányozták már, azonban a paracelluláris anyagtranszportra gyakorolt hatásuk ezidáig még nem volt ismert. A sejtéletképességi és hemolízis vizsgálatok hozzásegítettek az egyes α-CD-ek rangsorolásához, továbbá a vegyületek különböző rendszerekben mért toxikussága is összevethetővé vált. A megegyező kémiai módosításokon átesett α- és β-CD-ek biokompatibilitása rávilágított a CD-gyűrű mértének jelentőségére. Egyértelmű összefüggést fedeztünk fel a toxicitás és a szabad hidroxil-csoportok száma között. A hosszú alkil-csoporttal rendelkező CD-ek rossz oldékonysága további kémiai módosításokat tett szükségszerűvé; a szulfát csoportok jelenléte jótékony hatással volt az oldhatóságra, és a citotoxicitásra is. A szulfatálás a kalixarének oldékonyságát is növelte. A C4S és C8S vegyületek növelték a paracelluláris felszívódás mértékét szubtoxikus koncentrációban, azonban a C6S nem mutatott hasonló hatást. Ezen eredmények további kérdéseket vetnek fel a pontos hatásmechanizmusról. Eredményeink rávilágítanak a makrociklusok szerkezetének és biokompatibilitásának összefüggéseire, valamint ezen ismeretek fontosságára annak érdekében, hogy minden formulációban a legbiztonságosabb segédanyagok legyenek alkalmazhatóak
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Tran, Khoa V. "Spectroscopic studies of tetranuclear Pd(II) and Pt(II) macrocyclic square complexes." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1191722.
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Two macrocyclic squares (one with four Pd 21 corners, the other with four Pte+ corners) were synthesized according to literature methods."2 The charge-transfer complexes which formed when each were mixed with a bis(thiol)hydroquinone were then studied by UV-VIS, NMR, and IR spectroscopy. The UV-VIS data obtained indicated a stoichiometric relationship of I mole of molecular square to 2 moles of dithiol and a very large binding constant. Further evidence for the association between each macrocyclic square and the dithiol was observed in the NMR spectrum by the shifting of the proton resonances on the bipyridine unit of the molecular square and in the IR spectra by the changes in the aromatic ring absorptions of the dithiol and the bipyridine ring absorptions of the square.A monolayer formed on gold from a dilute solution of the dithiol in ethanol and a monolayer formed from a dilute solution of a 6:1 ratio of molecular square to dithiol were each observed by infrared grazing angle spectroscopy. The spectrum of the dithiol monolayer indicated that the aromatic ring was oriented perpendicular to the gold surface. The infrared spectrum of the square/dithiol monolayer showed the presence of triflate absorptions and methyl stretches, suggesting the square was attached via a catanane formation. Furthermore, the spectral data indicated that upon formation of the catanane, the aromatic ring of the dithiol and the bipyridine rings of the square were oriented parallel to the gold surface.Department of Chemistry
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Lacombe, Marie. "Synthesis and metal salt binding properties of functionalised macrocyclic ligands." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275160.
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Jami, Fatemeh. "The Synthesis of Biaryl Dicarboxaldehydes and their Application in the Synthesis of Polyimine Macrocycles and Macrocyclic Dynamic Combinatorial Libraries." Thesis, University of Surrey, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520479.
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Hamasharif, Muslih S. "Applications of azides in heterocyclic synthesis, macrocyclic synthesis and multicomponent reactions." Thesis, University of Huddersfield, 2016. http://eprints.hud.ac.uk/id/eprint/31079/.
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Cameron, Lynn Michele. "The design and synthesis of macrocycles for use as components of ion transporters." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0014/NQ32736.pdf.
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Laffan, D. D. P. "The synthesis of the macrocyclic skeleton of erythromycin." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254266.
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Bruder, Marjorie. "Synthesis of naturally occurring macrocyclic hydroquinones and oxephinochromones." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.523027.
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Al-Hiari, Yusuf. "Steps towards an efficient synthesis of macrocyclic bisbenzylisoquinolines." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366864.
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Chung, Lap-Yan. "Synthesis and study of macrocyclic and related compounds." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330163.
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Kostiuk, Sarah Louise. "The total synthesis of macrocyclic bisbibenzyl natural products." Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/193731/.
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This thesis is concerned with the total synthesis of two related macrocyclic natural products, cavicularin and riccardin C. Cavicularin is particularly noteworthy owing to its interesting structure: its 14-membered macrocyclic core imparts sufficient strain on the system to force one of the arenes in this paracycophane to adopt a boat-shaped conformation, deviating from planarity. The natural product also exhibits optical activity despite containing no chiral centres, this being due to axial and planar chirality in the molecule. Herein, routes to these two natural products are presented. Key steps include a highly chemoselective hydrogenation and a Wittig macrocyclisation and, in the case of cavicularin, regioselective halogenation and radical induced transannular ring contraction. This work also furnished a number of highly strained macrocycles as precursors to the natural products. These structures were found to contain boat-shaped aromatic rings, in addition to twisted olefin functionalities. A discussion of these features is presented in Chapter 6, with full crystallographic data provided in the Appendix. A review of these and related bisbibenzyl natural products is presented in Chapter 1, including their isolation, characterisation, an overview of their biological activity and previous synthetic work. Experimental procedures and characterisation data are provided in Chapter 7
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Chen, Mingfei III. "Macrocyclic Monomers: Synthesis, Characterization and Ring-opening Polymerization." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30720.
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Interest in macrocyclic monomers can be dated back to the 1960's. The recent surge of research activities in this area is prompted by two facts: the encouraging discovery of high yield synthesis and facile ring-opening polymerization of cyclic polycarbonate; the need for a technique to solve the tough processibility problem of high performance polymers.
This work was intended to address the following aspects in the cyclic poly(ether ketone) or sulfone system.
The first goal was to understand the structure-property relationship of this type of macrocycles. A large number of macrocycles were synthesized by nucleophilic aromatic substitution cyclization reactions under pseudo-high dilution conditions. Pure individual macrocycles as well as cyclic mixtures were characterized by NMR, HPLC, GPC, FABMS, MALDI-TOF-MS, DSC and TGA. Comparison study suggests that the cyclic distribution is kinetically controlled. Several factors determine the melting points of individual macrocycles. The first factor is the ring size. A series of cyclic monomers for poly(ether ether ketone)s were synthesized and isolated. The melting point decreases as ring size increases. Single crystal X-ray structural results suggest that this phenomenon is related to the increased flexibility of the larger sized macrocycles. The second factor is the functional groups of the macrocycles. X-ray structural and GPC experiments reveal that the sulfone group is more rigid than the ketone group, than ether group. The effect of functional groups on melting point is in the order sulfone>ketone>ether. A third factor is the symmetry of the macrocycles. Breaking the symmetry of macrocycle through comacrocyclization dramatically decreases the melting point of individual macrocycles as well as the cyclic mixture as a whole. Based on these findings, a novel two step method was developed to control the ring size distribution, which effectively reduced the amount of the small sized macrocycle and decreased the melting point.
In addition to the nucleophilic aromatic substitution cyclization, it was also demonstrated in this work that macrocycles can be synthesized by Friedel-Crafts acylation cyclization. However, this method is limited by the solubility problem.
The ring-opening polymerization of macrocyclic monomers was systematically studied. Several factors were considered in this study: the nature and amount of catalyst, temperature and time. CsF; metallic phenolate and Na2S are good initiators. Conversion to near 100 % is possible under the controlled polymerization conditions. It was found that crosslinking is an inherent phenomenon. The molecular weight of the soluble fraction near complete conversion is almost independent of initiator and polymerization temperature. It is limited by the crosslinking reaction. It is demonstrated for the first time that the macrocyclic monomer techniques can be applied to more valuable semicrystalline systems. Tough polymers such as high performance poly(ether ether ketone)s were produced through ring-opening polymerization.
The last chapter is devoted to the challenging synthesis of monodisperse poly(ether ether ketone)s. A convergent strategy was devised. A monofluoroaryl compound was synthesized by Friedel-crafts acylation reaction. The final monodisperse linear oligomers were generated by reacting the monofunctional compound with a bisphenol through a quantitative reaction.Ph. D.
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Mowbray, Charles Eric. "Arcimycins : selective degradation and semi-synthesis." Thesis, University of Exeter, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235913.
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Scott, Elinor L. "The synthesis and characterisation of novel 16-membered tetraazamacrocycles." Thesis, Heriot-Watt University, 1994. http://hdl.handle.net/10399/1391.
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Hébert, Normand C. 1930. "Methods for the synthesis of macrocyclic and bolaform phosphatidylcholines." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70273.
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A general strategy for the synthesis of phospholipids was developed. The method was demonstrated using 3-O-allyl-sn-glycerol 33 which was regiospecifically converted to 1-palmitoyl-2-(5-O-TBDMS-stearoyl)-3-O-allyl-sn-glycerol 43 by the sequential acylation of the primary and secondary hydroxyls. The allyl group was removed in two steps by isomerization to a vinyl ether and hydrolysis with N-bromosuccinimide in aqueous tetrahydrofuran. A new method for the conversion of the 1,2-diacylglycerols to phosphatidylcholines under acid-catalyzed conditions was developed. The diacylglycerols were treated with (2-bromoethyl)-($ 2$-cyanoethyl)-(N,N-diisopropylamino)-phosphoramidite 51 in the presence of tetrazole as catalyst, the phosphite triester was oxidized, and the neutral phosphate triester was treated with trimethylamine to simultaneously deprotect the phosphate and convert the bromoethyl substituent to the choline function. A modification was introduced to extend the synthetic strategy to unsaturated phosphatidylcholines. The starting material was 3-(4-methoxybenzyl)-sn-glycerol 30 (3-PMB-sn-glycerol). Diacylation of the hydroxyls with 13-tetradecynoic acid 64a followed by Glaser oxidation gave 1,2-(13,15-octacosadiyn-1-28-dioyl)-3-PMB-sn-glycerol 66. The 4-methoxybenzyl ether was cleaved using bromodimethylborane at $-$78$ sp circ$C in methylene chloride. The diacylglycerol 67 was converted to the phosphatidylcholine as before. Sequential acylation of 30 with palmitic acid and 15-hexadecynoic acid 64b followed by Glaser oxidation gave 2,2$ sp prime$-(15,17-dotriacontadiyn-1,32-dioyl)-bis- (1-palmitoyl-3-PMB-sn-glycerol) 72, which was converted to the bis-phosphatidylcholine 75 in the same manner as 66.
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Cerisoli, Lucia <1984>. "Synthesis and aplication of linear and macrocyclic nitrogen ligand." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5734/.
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Linear and macrocyclic nitrogen ligands have been found wide application during the years. Nitrogen has a much strong association with transition-metal ions because the electron pair is partucularly available for complexing purposes.
We started our investigation with the synthesis of new chiral perazamacrocycles containing four pyrrole rings. This ligand was synthesized by the [2+2]condensation of (R,R)-diaminocyclohexane and dipirranedialdehydes and was tested, after a complexation with Cu(OAc)2, in Henry reactions. The best yields (96%) and higher ee’s (96%) were obtained when the meso-substituent on the dipyrrandialdehyde was a methyl group. The positive influence of the pyrrole-containing macrocyclic structure on the efficiency/enantioselectivity of the catalytic system was demonstrated by comparison with the Henry reactions performed using analogous ligands. Henry product was obtain in good yield but only 73% of ee, when the dialdehyde unit was replaced by a triheteroaromatic dialdehye (furan-pyrrol-furan).
Another well known macrocyclic ligand is calix[4]pyrrole. We decided to investigate, in collaboration with Neier’s group, the metal-coordinating properties of calix[2]pyrrole[2]pyrrolidine compounds obtained by the reduction of calix[4]pyrrole. We focused our attention on the reduction conditions, and tested different Pd supported (charcoal, grafite) catalysts at different condition.
Concerning the synthesis of linear polyamine ligands. We focused our attention to the synthesis of 2-heteroaryl- and 2,5-diheteroarylpyrrolidines. The reductive amination reaction of diarylketones and aryl-substitutedketo-aldehydes with different chiral amines was exploited to prepare a small library of diastereo-enriched substituted pyrrolidines.
We have also described a new synthetic route to 1,2-disubstituted 1,2,3,4-tetrahydropyrrole[1,2-a]pyrazines, which involves the diastereoselective addition of Grignard reagents to chiral oxazolidines. The best diastereoselectivity (98:2) was dependent on the nature of both the chiral auxiliary, (S)-1-phenylglycinol, and the nature of the organometallic reagent (MeMgBr).
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Fernandez, Salazar Franz Rene. "A thermodynamic study on cation dibenzocryptand 222 and cation-dibenzo 18 crown 6 complexation in non-aqueous media." Thesis, University of Surrey, 1988. http://epubs.surrey.ac.uk/844484/.
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A general review on macrocyclic ligands with particular emphasis to dibenzocryptand 222 and dibenzo 18 crown 6 is given in the first part of the thesis (Chapter 1). This is followed by an exhaustive literature survey on the stability constants (hence free energies of complexing), enthalpies and entropies of metal cations with cryptands (dibenzocryptand 222, benzocryptand 222, cryptand 222) and crown ethers (dibenzo 18 crown 6, benzo 18 crown 6, 18 crown 6) in water and in non-aqueous solvents at 298.15 (Chapter 2). The experimental part (Chapter 3) also includes a detailed description of the principals involved in calorimetry as well as the methods used for the calculation of reaction enthalpies. Stability constant data for alkali-metal and silver cations with dibenzocryptand 222 in five dipolar aprotic solvents (N,N dimethyl-formamide, dimethylsulphoxide, acetonitrile, propylene carbonate and nitromethane) at 298.15 K are reported. These data are used to calculate the standard free energies of the complexation process involving metal(I) cations and dibenzocryptand 222 in the dipolar aprotic solvents. Free energy data are combined with enthalpy data obtained in this work in order to evaluate the entropies of complexation of these cations with dibenzocryptand 222 in these solvents. A linear correlation previously shown for metal(I) cations and cryptand 222 in DMF, Me2SO, AN, PC and NM between entropies of complexing and entropies of solvation of metal(I) cations in dipolar aprotic solvents is also found for dibenzocryptand 222. The results obtained in this thesis provide further evidence that the complexation process with metal (I) cations and cryptands is mainly controlled by the state of solvation of the cation in the solvent. Enthalpies of solution of dibenzocryptand 222 in the dipolar aprotic solvents are reported and the thermodynamic parameters for the extraction process in the water + nitromethane solvent system as described by M+(H2O) + 22B2B(NM) → M+22B2B (NM) are calculated (Chapter 4). Thermodynamic parameters of solution and transfer of dibenzo 18 crown 6 are discussed with respect to corresponding data for dibenzocryptand 222. The transfer free energies of metal ion dibenzocoronates from water to a number of solvents are calculated and it is shown that, unlike cryptates, there is an interaction between the complexed cation and the solvent in metal ion dibenzocoronates in dipolar aprotic media. Thermodynamic parameters of complexation for alkali-metal and dibenzo 18 crown 6 in acetonitrile are reported. The complexation process seems to be enthalpically and entropically controlled (Chapter 5). Synthesis of crown compounds and heats of solution of 18 crown 6 carried out at several temperatures as well as DeltaCp values in water are presented in Chapter 6.
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Nneoyi-Egbe, Ada Francesca. "The studies of novel peptide synthesis and macrocyclisation." Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=226984.
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N-carboxy-α-amino acid anhydrides (NCAs) are amino acid derivatives discovered by Leuch in 1906. Ever since, they have found invaluable use in the preparation of peptide drugs and polypeptides. NCAs are generally synthesised using phosgene; however, due to the hazardous nature of this chemical, safer method of synthesis using protected amino acids in the presence of activating reagents such as P2O4, T3P, HBTU and BOP-Cl were investigated, where a protonated oxazolone intermediate is dealkylated to generate the corresponding amino acid NCA. After the successful synthesis of a variety of NCAs, starting from Boc-protected amino acids and using T3P, we attempted to work out a new method of sequential peptide synthesis using NCAs in a controlled way. The challenge involved in the use of NCAs in the synthesis of peptides is to prevent decarboxylation of the intermediate products, which lead to the generation of unwanted peptide oligomers. An elegant way to prevent the decarboxylation was studied in this work, which consists of the stabilisation of the carbamate intermediates using an appropriate receptor. We prepared several carbamate receptors and tested them in model reactions using amines and NCAs under various conditions. Despites partial success in limiting the amount of oligomerisation, we were never able to prevent it completely, and could not established conditions to prepare peptides in good purity.
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Chen, Yang. "The syntheses and reactivity of polydentate PNNP ligands and macrocyclic polyphosphine ligands." HKBU Institutional Repository, 1998. http://repository.hkbu.edu.hk/etd_ra/220.
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Johnson, Charles Andrew. "Synthesis, characterization, and materials properties of benzocyclynes and metallabenzocyclynes /." view abstract or download file of text, 2007. http://proquest.umi.com/pqdweb?did=1400962601&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.
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Thesis (Ph. D.)--University of Oregon, 2007.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 243-262). Also available for download via the World Wide Web; free to University of Oregon users.
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Mann, Gregory. "Development of a biotechnological toolkit for the synthesis of diverse cyclic peptides." Thesis, University of St Andrews, 2017. http://hdl.handle.net/10023/10826.
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Cyclic peptides possess desirable characteristics as potential pharmaceutical scaffolds. The cyanobactin family of cyclic peptide natural products boast diverse structures and bioactivity. Exemplars are the patellamides, which have attracted attention due to their ability to reverse the effects of multi-drug resistance in human leukemia cells. In addition to their macrocyclic architecture patellamides contain azol(in)e heterocycles and d-amino acids. This structural complexity makes them challenging targets for chemical synthesis. Understanding their biosynthesis will enable the development of a biotechnological ‘toolkit' for the synthesis of new pharmaceutical compounds. Patellamides are ribosomally-synthesised and post-translationally modified peptides (RiPPs) and much of their biosynthesis has been elucidated, however there are still elements of their biosynthesis that are not yet fully understood. PatA and PatG contain C-terminal domains of unknown function (DUFs). The crystal structure of PatG-DUF has been solved and subsequent to biochemical and biophysical investigation PatG-DUF was found not to constitute an essential part of the biotechnological ‘toolkit' and can be excluded from in vitro enzyme-based synthesis of cyanobactin-like cyclic peptides. The cyanobactin heterocyclases are able to introduce heterocycles into a peptide backbone, seemingly irrespective of the neighbouring residues; however a molecular rational governing substrate recognition is unknown. Additionally the mechanism of heterocyclisaton is disputed. Analysis of crystal structures of LynD in complex with cofactor and substrate (solved by Dr Jesko Koehnke) enabled the active site and substrate recognition site to be located. A new mechanism for heterocyclisation has been proposed. Guided by the substrate recognition observed in complex structures a constituently active heterocyclase (AcLynD) has been engineered, which is able to process short, leaderless peptide substrates. Epimerisation in cyanobactin biosynthesis is believed to be spontaneous, but its precise timing is uncertain. NMR analysis of selectively labelled peptide substrates processed by the modifying enzymes, identified epimerisation to be spontaneous on the macrocycle, regardless of whether the neighbouring heterocycles have been oxidised. A one-pot in vitro synthesis of cyanobactins has been developed, and employed to create a number of patellamide D analogues to ascertain structural-activity relationships.
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Barbour, R. H. "Synthesis and biological activity of macrocyclic diesters of synthanecine A." Thesis, University of Glasgow, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.480493.
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Gao, Rui. "Design, synthesis, and optimisation of highly selective macrocyclic CDK9 inhibitors." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/50294/.
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Cyclin dependent kinases (CDKs) belong to a family of serine/threonine protein kinases that play a key role in cell cycle and transcriptional regulation. CDK9, in complex with its regulatory partner cyclin T1, is involved in RNA transcriptional regulation through phosphorylating the RNA polymerase II. Inhibition of CDK9 can target multiple cancer-relevant pathways by downregulating the transcriptionally inducible genes of cancer cells, such as cell cycle regulators and antiapoptotic factors. Although many CDK inhibitors have been in clinical trials, there is only one CDK9-selective compound (BAY1143572) in trials. Therefore, it is still necessary to study other highly selective CDK9 inhibitors. Through the analysis of the cocrystal structure of lead compound 5-(2-((3-(1,4-diazepan-1-yl)phenyl)amino)-pyrimidin-4-yl)-N,4-dimethyl-thiazol-2-amine (5) bound to CDK2 and CDK9, compound (5) favours the “inward” conformation in CDK9, while it adopts both the “inward” and “outward” conformations in CDK2. Aurora A and aurora B (ARKs) inhibitors are also found to adopt the similar “outward” conformation” in ATP binding site of ARKs. Therefore, an “inward” conformation macrocyclic structure was designed to improve the selectivity against CDK9 over CDK2 and ARKs. Three series of macrocyclic compounds were designed, synthesised and tested against CDK9, CDK2, and ARKs. The first series macrocyclic compounds with amide linker shows poor inhibitory activity against CDK9, and the molecular docking study shows these macrocyclic compounds fail to reside in the ATP binding site of CDK9. Following that, ring closing metathesis (RCM) was exploited as an alternative cyclisation strategy. Although the synthesis work was unsuccessful at the first onset, compound 6-methyl-12-oxa-3,6-diaza-2(4,2)-pyrimidina-1,4(1,3)-dibenzenacyclodo-decaphan-8-ene (43) with a similar structure as designed compounds was introduced as the model compound to optimise the RCM reaction. The thiazole group was then demonstrated to be the interfering factor in RCM and compound 11-oxa-3-aza-2(4,2)-pyrimidina-5(1,4)-piperazina-1,4(1,3)-dibenzenacyclo-undecaphan-7-ene (44) with a replacing phenyl group was successfully synthesised and showed poor activity against CDK2 and ARKs (>219 nM for these three kinases). According to the published paper regarding lead compound (5), extensive substituents modification (-CH3, -CN, -F) of compound (44) afforded 11-oxa-3-aza-2(4,2)-pyrimidina-5(1,4)-piperazina-1,4(1,3)-dibenzenacyclo-undecaphan-7-ene-1-carbonitrile (79) as the most selective CDK9 inhibitor. It shows 60-fold selectivity for CDK9 over CDK2 and 90-fold selectivity for CDK9 over ARKs. A further Diversity Kinase Profile Screening demonstrates the high selectivity of compound (79) that only tyrosine-protein kinase Lyn(h) appeared as the off-target. To improve the inhibitory activity against CDK9, alternative macrocyclic pyrimidine systems were designed, and compound 1-methoxy-4-(4-methylpiperazine-1-carbonyl)-3,8-diaza-2(4,2)-pyrimidina-1(1,3),4(1,2)-dibenzenacyclononaphan-7-one (89) showed an attractive Glide score based on molecular docking studies. Because of the time limit, the synthetic work for compound (89) has not been finished.
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Potter, Natalie Alison. "Synthesis of f-block complexes in a polypyrrolic macrocyclic environment." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/9562.
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In this thesis, the chemistry of lanthanide and actinide complexes of Schiff-base, polypyrrolic macrocyclic ligands has been evaluated. Chapter one introduces some general chemistry of uranium before focussing on uranium(III) and (IV) coordination complexes of nitrogen donor ligands. The surface chemistry of uranium metal is also briefly discussed along with the synthesis of uranium borohydride, hydride and alkyl complexes. Chapter two describes the synthesis and characterisation of the monometallic complexes [M(L)] or [M(HL)], where M = Y, Ce, and U, of the octadentate Schiffbase pyrrole macrocycle H4L. In particular, these complexes display a new binding mode of the macrocycle which leads to the formation of the unique trinuclear supramolecular complexes [M(HL)]3, (M = Ce, Y). Reactions of these materials towards hydrolysis, oxygen sources and other metal reagents are also exemplified. Chapter three details the synthesis and characterisation of the bimetallic complexes, [(MX)2(L)], where M = Ce, U, and Np and X = I or Cl, and [(MX2)2(L)], where M = U, and the attempts to transform these complexes into metal hydrides via their borohydrides. The solid state variable temperature magnetism of the binuclear U(III) and Np(III) complexes was recorded and was found to be consistent with the formation of iodide-bridged, polymeric structures. Chapter four explores the synthesis and reactions of adducts between UI3 and neutral macrocyclic ligands that incorporate either oxygen or nitrogen donors such as crown ethers and cyclam, respectively. The new synthesis of the key starting material, unsolvated UI3 is also outlined, along with the full characterisation of UI4(OEt)2.
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蔡美玉 and Mei-yuk Choi. "Synthesis and characterization of some organoruthenium complexes with macrocyclic amine ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31220654.
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Wong, Kam-cheung, and 王錦祥. "Lanthanide complexes containing macrocyclic ligands for magnetic resonance imaging contrast agents." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43278590.
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Qu, Tao. "Studies towards the total synthesis of the macrocyclic diamine alkaloid haliclonacyclamine C." Texas A&M University, 2004. http://hdl.handle.net/1969.1/2738.
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Marine sponges produce a series of complex polycyclic diamine alkaloids which appear to have a common biogenesis from simple bis-pyridine macrocycles. These structurally novel secondary metabolites are presumably biosynthetically produced by the controlled ionic coupling of macrocyclic 3-alkyl piperidines leading to 3,4??-linked bis-piperidines (ii). Included among these diamine marine alkaloids is haliclonacyclamine C
(i) which serves as our synthetic target. Chapter I in this thesis provides background information describing biological activity and proposed biosynthetic pathways to these important diamine marine alkaloids. Chapter II details progress towards the total synthesis of haliclonacyclamine C. The focus of Chapter II will be on our successful construction of the 3,4??-linked bispiperidine central core (ii) highlighted by the use of palladium-mediated C-C bond forming processes. The stereoselective hydrogenation of a coupled product will also be discussed.
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Marquez, Acuna Victoria Elena. "Coordination chemistry of macrocycles and metal complexes containing a nitrogen and sulphur donor set." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279727.
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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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Maiti, Tushar B. (Tushar Baran). "An Approach Towards the Total Synthesis of Clonostachydiol." Thesis, University of North Texas, 1995. https://digital.library.unt.edu/ark:/67531/metadc278800/.
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The syntheses of the unsymmetrical 14-membered bismacrolides have been reviewed. A total synthesis of clonostachydiol, the latest to join this family, has been attempted using trimethylsilyl acetylene as the builiding block and palladium catalyzed reactions for the formation of key bonds. The alkyne groups were introduced by Stille coupling of trimethylstannylethynyltrimethylsilane with an acid chloride for one fragment and by addition of lithiotrimethylsilyl acetylene to an aldehyde for the other. Lactic acid derivatives were chosen as starting materials for both fragments, thus introducing two of the chiral centers. The remaining stereocenters were introduced using stereoselective reductions of ketones.
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Thibault, Michelle Elizabeth, and University of Lethbridge Faculty of Arts and Science. "Novel bis(isobenzofuran)s and their utility in the synthesis of cyclophanes." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2003, 2003. http://hdl.handle.net/10133/239.
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The synthesis of 1,2-bis(5-isobenzofuranyl)ethene by two routes is described. The first route involved generation of 1,2-bis(5-isobenzofuranyl)ethene from a bis(acetal) precursor under basic conditions. However, the synthesis was lengthy with low-yielding steps, which led to it being abandoned. The second route involved generation of 1,2-bis(5-isobenzofuranyl)ethene from a bis(oxabicyclic) precursor with 3,6-di(2'-pyridyl)-s-tetrazine. Napththo[1,2-c:5,6-c] difuran and 1,2-bis(5isobenzofuranyl)ethene were used to construct novel cyclophanes by double Diels-Alder reactions with bis(maleimide)s. NMR, AM1 modeling, and X-ray studies of the cyclophanes are discused. Attempts to prepare phenanthro[2,3-c:6,7-c] difuran and its cyclophanes are discussed. None was successful, and investigations were hampered by the inability to obtain sufficient quantities of starting materials. Finally, several suggestions are given for improving the syntheses of 1,2-bis(5-
isobenzofuranyl)ethene, phenanthro[2,3-c:6,7-c]difuran, and their cyclophanes. Future directions, such as the functionalization of the double bond of 1,2-bis(5-isobenzofuranyl)ethene, aromatization of the oxabicyclic rings of the cyclophanes, and further X-ray studies are discussed.x, 122 leaves : ill. ; 28 cm.
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Choi, Mei-yuk. "Synthesis and characterization of some organoruthenium complexes with macrocyclic amine ligands /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20667978.
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Sieber, Stephan Axel. "Nonribosomal peptide synthetases quaternary structure and chemoenzymatic synthesis of macrocyclic peptides /." [S.l.] : [s.n.], 2004. http://archiv.ub.uni-marburg.de/diss/z2004/0218/.
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Brooker, Sally Anne. "Synthesis and characterisation of polynuclear complexes with macrocyclic and related ligands." Thesis, University of Canterbury. Chemistry, 1989. http://hdl.handle.net/10092/7566.
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This thesis is in two distinct but related parts. The first deals mainly with manganese complexes of multinucleating Schiff-base macrocycles derived by condensation of 2,6-diacetylpyridine (DAP) and 1,3-diamino-2-hydroxypropane (H₂L1, H₄L1'), or 1,3-diaminopropane (L13). Six tetramanganese(II) complexes of H₂L1 and H₄L1', three pentamanganese(II) complexes of H₂L1 and one mixed-valence manganese(II)₂manganese(III)₃ complex of L13 were synthesised and characterised by single crystal X-ray structure analysis. A mechanism for the observed ring expansion reaction from the (2+2) macrocycle (H₂L1) to the (4+4) macrocycle (H₄L1') is proposed and supported by the results of ²⁵²Cf PDMS, conductivity and EPR measurements. Possible reasons for the isolation of three pentamanganese(II) complexes as well as a tetramanganese(II) complex of H₂L1 in the presence of acetate ions are discussed. The mixed-valence complex of L13 has led to the proposal of a new mechanism for water oxidation by the OEC (oxygen evolving complex) of photosystem II in green plants. The complexes are discussed in terms of their relevance as models for the OEC. This includes discussion of the results of EXAFS (Extended X-ray Absorption Fine Structure), XANES (X-ray Absorption Near Edge Spectroscopy), cyclic voltammetric and magnetic susceptibility studies. An unusual eight-coordinate manganese(II) complex of DAP was prepared and structurally characterised, as was a macrocyclic dilead complex with unusual single atom bridging via the nitrogen atom of a thiocyanate ligand.
Less constrained noncyclic ligands are described in the second Section. These are related to the macrocyclic systems, and are derived from the condensation of formyl- or acetylpyridine derivatives with 1,n-aminoalcohols. Particular emphasis was given to manganese complexes because of their potential relevance to the OEC. Two ligand rerrangement reactions, involving the pyridine nitrogen and resulting in the formation of five-membered rings, were observed and possible mechanisms are proposed. Sixteen single crystal X-ray structure determinations were performed including those of eight manganese(II) complexes.
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Murgues, Paul Gabriel. "New approaches towards the total synthesis of macrocyclic bisbenzyl natural products." Thesis, University of Southampton, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.664978.
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The macrocyclic bisbibenzyls are a family of natural products generally extracted from species of liverworts. They have attracted considerable attention from synthetic chemists as they display an interesting array of biological activities. Furthermore, as each contains a strained cyclophane core, they present an interesting challenge to the synthetic chemist. Many total syntheses have been published, but to date no general strategy based on robust conditions has been established. The thesis describes our attempts to establish such an approach for the synthesis of the macrocyclic bisbibenzyl family of natural product. The discussion is divided in two independent parts. The first approach described sought to generalise an existing approach that had proven successful for the synthesis of a few macrocyclic bisbibenzyl natural products. A key of that strategy was the use of palladium-catalysed cross-coupling reactions to unite key fragments. The synthetic plan was redesigned for the general case and rationalised in light of difficulties reported in the existing literature. Over 20 potential coupling precursors were synthesised in a few high-yielding steps and their behaviour examined in Suzuki-Miyaura cross-coupling reactions using various reaction protocols. A suitable combination of precursors and catalyst was found to afford many of the desired biaryl products in high yields, though further investigation is required to advance these to the natural product targets. The second strategy was based on a bidirectional approach and a biomimetic ring closure. The synthesis of acyclic precursors by means of Sonogashira and Heck couplings gave disappointing results. The use of Wittig olefination provided an excellent synthetic route to the required bisbibenzyl macrocyclisation precursors. Alas, none of the envisioned macrocyclisation reactions succeeded.
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Limon, Matthieu. "Synthesis and coordination chemistry of functionalised and macrocyclic phosphines and arsines." Thesis, Cardiff University, 2009. http://orca.cf.ac.uk/54767/.
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The results presented in this thesis are separated into three distinct sections. Chapter 2 describes the reaction of the manganese precursors Mn(OTf)(CO)3{o-C6H4(PH2)2}L 2.6, and Mn(OTf)(CO)3{C2H4(PH2)2} / 2.7, with a silver carbene transfer agent 1,3-dialtylbenzimidazol-2-ylidiene, 2.10, to give the new phosphido-phosphine manganese species 2.11 and 2.12. The resultant species 2.11 and 2.12 exist in two geometric forms, cis and trans, which have been characterised by X-Ray crystallography for 2.11. A new chiral rigid phospholane ligand 3(/)-hydroxy-phenylphospholane, 3.7, has been prepared from the reaction of phenylphosphine with enantiopure (/)-2-(oxiran-2-yl)ethyl-4-methylphenylsulfonate, 3.4. In order to enlarge the family of heterocyclic coordinated complexes, we herein report in Chapter 3 the synthesis of compounds Mo(k-PR s-3.7)2(CO)4, 3.16, Re(CO)5(k-PR,s-3.7), 3.17, Mn(OTf)(CO)4(k-PRfs-3.7), 3.18, Ru(cymene)a(k-PR,s-3.7), 3.19, FeCp'(CO)2(k-PR,s-3.7) PF6, 3.20, Rh(cod)CI(k-PR,s-3.7), 3.21, c/s-(k-PR,s-3.7)2PtCI2, 3.22, c/s-(k-PRfs-3.7)2PdCI2, 3.23. Finally, Chapter 4 presents the synthesis of new tribenzannulated dtarsine monophosphine macrocycle complexes prepared by a template method via dehydrofluorinative cyclisation of the di-ortfio-fluorophenylbisarsinobenzene ligand with PhPH2 at Mn(CO}3 + or Re(CO)3 + templates. The new macrocycles formed may expand the scientific understanding about phosphorus and arsenic chemistry. In order to enlarge this knowledge, other ways to introduce diarsenic ligands in our case 1,2-bis(arsino)benzene, 4.a, on a metal centre were attempted on MnBr(CO)5, 4.2, Mn(OTf)(CO)5, 4.3, Mn(CO)3(NCCH3)3 PF6, 4.4, Mn(CO)3(ace)3 PF6, 4.5, ReBr(CO)5, 4.6, Mn(OTf)(CO)5, 4.7, Cr(CO)3(NCCH3)3, 4.8, and Mo(CO)3(NCCH3)3, 4.9, precursors but no discrete complexes could be isolated and characterised.
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Gramage-Doria, Rafael. "Large cavity cyclodextrin-based macrocyclic ligands : synthesis, coordination and catalytic properties." Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00767168.
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Cyclodextrins (CDs) are cyclic oligosaccharides of various sizes containing several α-(1→4)-linked D-(+)- glucopyranose units. The commercially available ones comprise six, seven or eight glucose units, named respectively α-CD, β-CD and γ-CD. Their truncated cone-like and well-defined cavity are particularly attractive for the encapsulation of a variety of substrates. As such, they found numerous applications in many areas of chemistry. A recent development, from which the present work is inspired, consisted in covalently linking transition metals to CD cavities in order to perform and study catalytic reactions in a confined environment featuring steric repulsive or attractive noncovalent interactions with the substrate or/and the metal coordination sphere.The first part of this thesis focuses on reviewing transition metal-based cavitands, for which the first and second metal coordination spheres are controlled by their cavity-shaped ligand. The following chapters are concerned with the synthesis, coordination and catalytic properties of two new phosphane ligands built on a large β-CD scaffold. The first one, named WIDEPHOS, is a diphosphine having two phenylphosphinidene "PPh" units capping adjacent glucose units on a methylated β-CD. This ligand features two phosphorus lone pairs pointing to the cavity interior but not aligned. These geometrical features, combined with the large distance separating the two phosphorus atoms, promote the formation of "imperfect" trans-chelate complexes in which the metal centre swings about the ligand. This unprecedented molecular movement, christened "oschelation", allows each phosphorus atom to form an optimal bond in turn with the coordinated d8 and d10 transition metal ions. Further studies on WIDEPHOS proved that it is better suited for coordinating dinuclear fragments within the confinement of the large β-CD cavity. Severe steric constrains on the metal first sphere of coordination result in the formation of single μ-chlorido bridged dinuclear species. In this new type of square planar complexes, non-optimal orbital overlapping measured by the so-called tilt angle was also found to take place for one of the phosphorus atom together with an "oschelation" movement involving non identical donor atoms, namely a phosphorus and an oxygen atom. Static gold(I) dinuclear complexes displaying similar imperfect orbital overlapping for one of the phosphorus atom were also prepared.
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Pernia, Glen Javier. "Synthesis and binding properties of novel macrocyclic receptors for amino acids." Thesis, University of Southampton, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296273.
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Paquet, Tanya. "Total synthesis of phorbaside A and the macrocyclic core of leiodermatolide." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609798.
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Hesford, Matthew James. "Synthesis and coordination chemistry of acyclic and macrocyclic tellurium-containing ligands." Thesis, University of Southampton, 2003. https://eprints.soton.ac.uk/361577/.
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McCroskey, Lucas C. "Synthesis of a Novel Macrocyclic Library and Small-Molecule Peptide Scaffolds." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1449158858.
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Chang, Shuh-Kuen. "Studies toward the total synthesis of amphidinol 3." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1150261354.
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Khene, Mielie Samson. "Synthesis, photophysics and electrochemical study of tin macrocycles." Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1005041.
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Three non-peripherally substituted tin(IV) macrocylic compounds, octahexylphthalocyaninato dichlorotin(IV) (35a), octahexyltetrabenzo-5,10,15-triazaporphyrinato dichlorotin(IV) (35b) and octadecylphthalocyaninato dichlorotin(IV) (35c) were synthesized and their photophysical and electrochemical behaviour studied. Complex (35b), containing a CH group in place of one of the aza nitrogen atom of the phthalocyanine core, shows a split Q band due to its lower symmetry. The triplet state quantum yields were found to be lower than would be expected on the basis of the heavy atom effect of tin as the central metal for phthalocyanine derivatives (35a and 35c). In contrast, (35b) shows a triplet quantum yield ΦT = 0.78. The triplet state lifetimes were solvent dependent, and were higher in THF than in toluene. Cyclic voltammetry and spectroelectrochemistry of the complexes revealed only ring based redox processes. This thesis also reports on the microwave syntheses of tetrasulphonated tin phthalocyanine and tetrasulphonated tin α,β,γ-tetrabenzcorrole. The latter was only formed at low ratios (< 1:8) of 4-sulfophthalic acid to urea. Both complexes are aggregated in aqueous media, but can be partly or fully disaggregated by the addition of Triton X-100. The SnTSTBC complex has lower triplet life times and yields, while binding constant and quenching (of bovine serum albumin) constant are lower for SnTSTBC, compared to SnTSPc. Finally Non-peripherally (α) tetra- (40) and octa-(38a) substituted dodecyl-mercapto tin(IV) phthalocyanines where synthesized and the electrochemical behavior studied. Cyclic voltammetry and spectroelectrochemistry show ring-based reductions for (38a) and (40); the former shows two ring oxidations, while the latter shows only one ring based oxidation. The adsorption kinetics of (38a) and (40) on a gold electrode have been investigated by electrochemical impedance spectroscopy (EIS). The equilibrium constant (K) for the adsorption and the Gibbs free energy ΔG(ads) of the self-assembled monolayer (SAMs) were evaluated based on the Frumkin isotherm. The interaction factor between adsorbate –adsorbate molecules is also discussed.