Dissertations / Theses: 'Supramolecular chemistry; Molecular recognition'

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Kerdelhue, Jean-Luc. "The higher paracyclophanes : potential receptors for the molecular recognition of molecular halogens and benzenes." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307819.

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Rajbanshi, Arbin. "Supramolecular interactions from small-molecule selectivity to molecular capsules." Diss., Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/3879.

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Agostini, Alessandro. "Supramolecular and heterosupramolecar chemistry in controlled release and molecular recognition processes." Doctoral thesis, Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/29397.

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La presente tesis doctoral titulada ¿Supramolecular and heterosupramolecular chemistry in controlled release and molecular recognition processes¿ está centrada en los dos aspectos principales de la química supramolecular que han experimentado un gran auge en los últimos años: el reconocimiento molecular y los procesos de liberación controlada. En particular la primera parte de la tesis se focaliza en el diseño y síntesis de moléculas orgánicas que pueden ser empleados cómo sensores para especies aniónicas y neutras. El paradigma seleccionado para los procesos de reconocimiento molecular fue la aproximación del dosimetro químico. Esta aproximación presenta ventajas con respecto a los otros dos métodos de determinación de aniones (desplazamiento y unidad coordinanteunidad indicadora), cómo, por ejemplo, la posibilidad de determinar los analitos en disolución acuosa. Así se sintetizaron dos sensores selectivos, uno para el anión fluoruro (F-) y el otro para glutatión (GSH). El sensor selectivo para la determinación de F- está basado en un colorante azoico funcionalizado, en su ¿OH fenólico, cómo silileter. Esta molécula presenta una banda de absroción muy intensa centrada a 350 nm que, después de la adición de F- , sufre un efecto hipocrómico significativo y un desplazamiento batocromico ligero (de ca. 10 nm), mientras aparece una nueva banda a 470 nm, determinando un cambio de incoloro a amarillorojo. Para obtener un sensor selectivo para GSH se sintetizó una sonda químico basado en una sal de 2,6-difenilpirilio. Sucesivamente se preparó una disolución de este compuesto en agua/CTAB, que se caracterizaba por un intenso color azul. En este caso, la adición de GSH produce una disminución significativa de la banda del visible, acompañada por la consecuente decoloración. Además la adicón de GSH induce la aparición de Resumen vi una intensa banda de emisión centrada a 485 nm (después de la irradiación a 350 nm). La segunda parte de esta tesis doctoral se basa en el diseño y síntesis de nuevos sistemas híbridos orgánicos-inorgánicos para procesos de liberación controlada en ambiente celular. Estos materiales híbridos se componen en general, de dos unidades: una matriz inorgánica mesoporosa de base silícea, capaz de almacenar moléculas orgánicas (colorantes, farmacos...) y un compuesto orgánico anclado covalentemente a la superficie externa del soporte inorgánico mesoporoso, que actúa cómo puerta molecular. La aplicación de un estímulo externo puede modificar la conformación de la puerta molecular permitiendo o bien impidiendo la difusión de la carga almacenada en los mesoporos hacía el exterior (disolución o citoplasma). El primer sistema sintetizado y estudiado se compone de una matriz inorgánica mesoporosa (MCM-41), cargada con el colorante Ru(bipy)3 2+ y funcionalizada en la superficie con un oligoetilen glicol mediante un grupo ester. La adición de la enzima esterasa determinaba la hidrólisis del grupo ester y la consecuente reducción del tamaño de la puerta molecular, acompañada por la liberación del colorante previamente cargado. Otro sistema de liberación preparado consiste en el uso de la misma matriz MCM-41 nanoscópica y el mismo colorante Ru(bipy)3 2+, pero se funcionalizó la superficie con una puerta molecular fotolabil. La irradiación en el maximo de absorción de la puerta molecular inducía la fotodegradación de la misma y la consecuente liberación del colorante. Un tercer ejemplo de sistema de liberación consiste en una puerta molecular caracterizada por la presencia de dos grupos funcionales hidrolizables con enzimas diferentes: grupos urea y amida. vii El material final, caracterizado por la presencia del mismo esqueleto inorgánico, y cargado con Ru(bipy)3 2+, era capaz de liberar selectivamente cantidades distintas de colorante, dependiendo del enzima empleado. Así se podían conseguir dos tipos de perfiles de liberación: uno muy rápido y poco intenso y otro más lento pero mucho mas intenso. Finalmente se sintetizó un material híbrido siempre basado en la misma matriz de MCM- 41, cargado con rodamina-B y funcionalizado en la superficie con galactooligosacáridos. Con este material se podía conseguir una liberación controlada del colorante selectivamente en células senescentes, debido a que estas sobreexpresan el enzima ß-galactosidasa que es capaz de hidrolizar los galactooligosacáridos.
Agostini, A. (2013). Supramolecular and heterosupramolecar chemistry in controlled release and molecular recognition processes [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/29397
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South, Clinton Ray. "Polymer side-chains as arms for molecular recognition." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22667.

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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2008.
Committee Chair: Weck, Marcus; Committee Member: Beckham, Haskell; Committee Member: Bunz, Uwe; Committee Member: Jones, Christopher; Committee Member: Marder, Seth.

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Welideniya, Dhanushi Thathsara. "Supramolecular chemistry of small molecular fundamentals to drug–receptor applications." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/19106.

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Doctor of Philosophy
Department of Chemistry
Christer B. Aakeroy
A family of bis-pyridine based pharmaceutical active ingredients were synthesized and co-crystallized with four iodoperfluoroalkanes. Thirteen new crystal structures that are driven by I‧‧‧N(py) halogen bonds, are presented and compared with that of their hydrogen-bonded analogues. Halogen bonded co-crystals exhibit two different structural arrangements, as opposed to layered architectures observed in hydrogen bonded co-crystals. In order to explore the effect of aromatic stacking interactions on hydrogen and halogen bond driven co-crystallization process, we utilized a series of aromatic hydrogen and halogen bond donors in combination with bis-pyridine based pharmaceutical active ingredients. Aromatic stacking between the donor and the acceptor were limited, due to the lack of complementarity between the donor and the acceptor in terms of size, shape and geometry. In that case, homomeric interactions between the single components were translated into the structure of the binary co-crystals. According to our charge calculations, similarly activated hydrogen and iodine atoms possess similar electrostatics. Therefore, we wanted to investigate the interchangeability of hydrogen bonds and halogen bonds by utilizing 2-aminopyrimidine as the backbone for C(sp)-H and C(sp)-I functionalities which makes self-complementary ribbons via NH‧‧‧N synthons. Our results show that the ethynyl proton is capable of acting as a synthon mimic of ethynyl iodine by interchangeable C(sp)-H‧‧‧N hydrogen bonds and C(sp)-I‧‧‧N halogen bonds. We exploited the halogen bonding donor capability of iodo, bromo and chloro ethynyl functionalities towards a series of halide ions. Based on the grinding experiments these donors showed 90%, 70% and 50% success rates towards halides. Among the halides, chlorides exhibited the highest red shift compared to bromides and iodides. We synthesized a series of cavitands functionalized with hydrogen bond donor and acceptor groups and studied their binding preferences towards a series of active ingredients. We have shown that suitably functionalized cavitands can act as carriers of active ingredients and especially, selective binding of aspirin is demonstrated using a two-point binding mode.

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D'Souza, Lawrence Joseph. "Bile Acid Based Molecular Tweezers And Crown Ethers." Thesis, Indian Institute of Science, 1995. http://hdl.handle.net/2005/114.

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Chapter 1. Introduction to Molecular Tweezers Whitlock and Zimmerman developed a class of molecular hosts, popularly known as molecular tweezers, which sandwich aromatic guests by ii=ii interaction. Chapter 1 summarizes molecular tweezers of various kinds which have recently been synthesized. Chapter 2. Design and synthesis of "Bile Acid-Based Molecular Tweezers" Bile acids have a rigid backbone, and the array of hydroxyl groups separated by 5-7 A provides opportunities for the attachment of binding surfaces such as two extended chromophoric units.

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Gardlik, Matthew Michael. "Design, synthesis, and encapsulation processes of molecular baskets." Columbus, Ohio : Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1243536105.

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Tiwari, Laxmikant. "Design and synthesis of novel anion receptors." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312677.

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Shade, Matthew. "Redox-active calixarenes as receptors for anions and neutral molecules." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242875.

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De, la Torre Paredes Cristina. "Nanotechnology and supramolecular chemistry in controlled release and molecular recognition proceses for biomedical applications"." Doctoral thesis, Universitat Politècnica de València, 2018. http://hdl.handle.net/10251/94043.

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La presente tesis doctoral, titulada "Nanotecnología y química supramolecular en procesos de liberación controlada y reconocimiento molecular para aplicaciones biomédicas", se centra en dos temas importantes: el reconocimiento molecular y los procesos de liberación controlada. Esta tesis doctoral está estructurada en cuatro capítulos. El primer capítulo introduce el concepto de materiales híbridos orgánicos-inorgánicos funcionalizados con puertas moleculares y sus aplicaciones biomédicas como nanomateriales para dirigir y controlar la liberación controlada de fármacos. Además se introduce una breve descripción sobre sensors colorimétricos basados en la base de la quimica supramolecular, particularmente en los procesos de reconocimiento molecular. En particular, el capítulo 2 describe la preparacion de cinco nanodispositivos que responden a enzimas. Estos materiales híbridos se componen de dos unidades principales: un soporte mesoporoso basado en sílice inorgánica, capaz de encapsular moléculas orgánicas y un compuesto orgánico anclado en la superficie externa del soporte mesoporoso inorgánico que actúa como puerta molecular. Todos los sistemas propuestos utilizan puertas moleculares peptídicas que responden a temperatura o enzimas como estímulo. La segunda parte de esta tesis doctoral se centra en el diseño y desarrollo de un nuevo compuesto químico capaz de detectar monóxido de carbono in vivo. En resumen, para todos los resultados antes mencionados podemos decir que esta tesis doctoral constituye una contribución científica original al desarrollo de la química supramolecular. Sus resultados derivados de los estudios presentados dejan rutas abiertas para continuar el estudio y el desarrollo de nuevos materiales híbridos y sensors químicos más eficientes para aplicaciones biomédicas y terapeuticas.
This PhD thesis entitled "Nanotechnology and supramolecular chemistry in controlled release and molecular recognition processes for biomedical applications", is focused on two important subjects: molecular recognition and controlled delivery processes. This PhD thesis is structured in four chapters. The first chapter introduces the concept of organic-inorganic hybrid materials containing switchable "gate-like" ensembles and their biomedical applications as nanomaterials for targeting and control drug delivery. Furthermore, is introduced a short review about chromo-fluorogenic chemosensors based on basic principles of supramolecular chemistry, particulary in molecular recognition processes. In particular, in chapter 2 is focus on the development of enzymatic-driven nanodevices. These hybrid materials are composed of two main units: an inorganic silica based mesoporous scaffold, able to store organic molecules and an organic compound anchored on the external surface of the inorganic mesoporous support than acts as molecular gate. All the systems proposed use peptidic gates that respond to temperature or enzimatic stimulis. The second part of this PhD thesis is focused on the design and development of a new chemical compound capable of detecting carbon monoxide in vivo. In summary, for all the results above mentioned we can say that this PhD thesis constitutes an original scientific contribution to the development of supramolecular chemistry. Its results derived from the studies presented leaves open routes to continue the study and development of new hybrid materials and more efficient chemical sensors with biomedical and therapeutic applications.
La present tesi doctoral, titulada "Nanotecnologia i química supramolecular en processos d'alliberament controlat i reconeixement molecular per a aplicacions biomèdiques", es centra en dos temes importants de la química: el reconeixement molecular i els processos d'alliberament controlat. Aquesta tesi doctoral està estructurada en quatre capítols. El primer capítol introdueix el concepte de materials híbrids orgànics-inorgànics funcionalitzats amb portes moleculars i les seves aplicacions biomèdiques com nanomaterials per dirigir i controlar l'alliberament controlat de fàrmacs. A més s'introdueix una breu descripció sobre sensors colorimètrics fonamentats en la base de la química supramolecular, particularment en els processos de reconeixement molecular. En particular, el capítol 2 descriu la preparació de cinc nanodispositius que responen a enzims. Aquests materials híbrids es componen de dues unitats principals: un suport mesoporos basat en sílice inorgànica, capaç d'encapsular molècules orgàniques i un compost orgànic ancorat a la superfície externa del suport mesoporós inorgànic que actua com a porta molecular. La segona part d'aquesta tesi doctoral es centra en el disseny i desenvolupaent d'un nou compost químic capaç de detectar monòxid de carboni in vivo. En resum, per a tots els resultats abans mencionats podem dir que esta tesi doctoral constituïx una contribució científica original al desenvolupament de la química supramolecular. Els seus resultats derivats dels estudis presentats deixen rutes obertes per a continuar l'estudi i el desenvolupament de nous materials hibrids i sensors químics més eficients per a aplicacions biomèdiques i terapeutiques.
De La Torre Paredes, C. (2017). Nanotechnology and supramolecular chemistry in controlled release and molecular recognition proceses for biomedical applications" [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/94043
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Coskun, Ali. "Ion Sensing And Molecular Logic In Supramolecular Systems." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12608736/index.pdf.

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Supramolecular chemistry is an emerging field of chemistry which has attracted much attention in recent years as a result of its broad applicability in many areas. Thus, the design of functional supramolecular systems is strongly in demand in this field. For this purpose, we have developed ratiometric fluorescent chemosensors for ion sensing and mechanically interlocked structures for their application in molecular logic. In the first part, we report a novel dimeric boradiazaindacene dye which can be converted in one step to an efficient resonance energy transfer (RET) dyad. In addition, if this modification is done with appropriate ligands, RET can be coupled to ion sensing. The utility of this approach is demonstrated in a highly selective, emission ratiometric chemosensor for Ag(I). In the second part, boradiazaindacene dyads designed as energy transfer casettes were modified to signal cation concentrations ratiometrically. If the energy transfer efficiency is increased by changing spectral overlap on cation binding, an enhancement of emission signal ratios can be obtained. A larger range of ratios results in highly improved sensitivity to analyte concentrations. We demonstrate this approach in a de novo design of a novel and highly selective ratiometric chemosensor for Hg(II) ions. In the last part, we synthesized a two-station [2]catenane composed of an &
#960
-electron rich bis-1,5-dihydroxynapthalene[38]-crown-10 (1/5DNPC10) ring interlocked with a second macrocycle containing two &
#960
-electron deficient unit, namely, napthodiimide (NpI) and bipyridinium (BIPY)2+ unit using the Cu(I)-catalyzed Huisgen 1,3-cycloaddition reaction. The resulting bistable [2]catenane is isolated as a single co-conformation which is comprised of the 1/5DNP[38]C10 ring around the NpI unit. Thermal activation of the pure NpI-isomer at 70&
#730
C for 60 h leads to the formation of the BIPY2+-isomer by virtue of the circumrotation of the crown-ether ring along the backbone of the other macrocycle over the steric barrier of the tetra-aryl methane units. The energy barrier for the circumrotation is 28.5±
0.3 kcal/mol. Electrochemistry of a 1:1 mixture of the two possible isomers shows that the [2]catenane cannot be switched mechanically on account of the large steric barriers presented by the tetra-aryl methane groups on the electron-accepting ring.

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Zhang, Dawei. "Hemicryptophanes and Beyond : Synthesis, Recognition, Molecular Machines and Supramolecular Catalysis." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEN011/document.

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Les hémicryptophanes, molécules constituées d’une unité cyclotriveratrylène (CTV) reliée à un autre groupement de symétrie C3, sont des molécules cages qui trouvent de nombreuses applications dans le domaine de la chimie hôte-invité. Dans une première partie, ce manuscrit présente une revue des développements récents de la chimie des hémicryptophanes et définit les objectifs de ce travail de thèse.Nos travaux concernent principalement le design d'hémicryptophanes spécifiquement conçus pour la reconnaissance moléculaire de substrats d'intérêt. Ainsi, des structures variées d'hémicryptophanes ont été conçues comme capteur fluorescent du phosphate de choline, ou pour la reconnaissance de paire d'ions. Des hémicryptophanes hétéroditopiques originaux portant des unités tris(2-pyridylmethyl)amine (TPA) ont été synthétisés et présentent un grand intérêt pour des applications ultérieures en reconnaissance. Nous avons étudié la reconnaissance stéréosélective de saccharides avec des hémicryptophanes énantiopurs qui associent trois types de chiralité sur sept centres stéréogènes. Enfin, nous décrivons le mouvement de "respiration" moléculaire de cages énantiopures, enrichissant ainsi les rares applications des hémicryptophanes comme machines moléculaires.Des complexes du vanadium(V) des hémicryptophanes ont été développés comme catalyseurs efficaces dans des réactions de sulfoxydation et pour l'oxydation catalytique de lignines. Des dérivés azaphosphatrane d’hémicryptohanes ont été développés comme organocatalyseurs de la réaction de polymérisation par ouverture du lactide. La dernière partie de ce manuscript est consacrée à des développements nouveaux dans le domaine de la formation de cages par auto-assemblage. Nous avons réussi à former par coordination des tétraèdres dont les quatre faces comportent une sous-unité azaphosphatrane. Nous montrons pour la première fois que dans ce type de cage l’unité azaphosphatrane joue un rôle prépondérant dans la complexation d’anions
In the wide area of host-guest chemistry, hemicryptophanes, a type of molecular cages combining a cyclotriveratrylene (CTV) unit with another different C3 symmetrical moiety, have received increasing attention. In a first part of this work, the advances in hemicryptophane chemistry have been thoroughly reviewed and the objectives of the thesis have been postulated. Our work mainly concerns the targeted molecular recognition by rational design of hemicryptophanes. Various hemicryptophane structures have been designed as fluorescent sensors for choline phosphate, or for ion-pairs recognition. Original heteroditopic hemicryptophanes bearing tris(2-pyridylmethyl)amine (TPA) units have been synthesized that present a great interest for further applications in molecular recognition. We investigated the stereoselective recognition of carbohydrates using enantiopure hemicryptophanes combining three classes of chirality on seven stereogenic units. At last, we described the breathing motion of a series of enantiopure cages, complementing the rare application of hemicryptophanes as molecular machines.Hemicryptophane vanadium(V) complexes, have been developed as efficient supramolecular catalysts for sulfoxidation and for the catalytic lignin oxidation. Azaphosphatrane-functionalized hemicryptophanes were developed as hydrogen-bonding organocatalysts for the ring-opening polymerization of lactide. Finally, my attention has opened to a more prospective view focusing on cages constructed by self-assembly, and we have demonstrated the feasibility of introducing azaphosphatrane moieties into tetrahedron capsules using subcomponent self-assembly, and also proved for the first time the utility of azaphosphatranes as anion binding moieties

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Vidonne, Annick. "Integrating replication processes with mechanically interlocked molecules." Thesis, St Andrews, 2009. http://hdl.handle.net/10023/913.

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Forbes, Safiyyah. "Hydrogen-bond driven supramolecular chemistry for modulating physical properties of pharmaceutical compounds." Diss., Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/3756.

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Ioup, Sarah E. "Water-Soluble Deep-Cavity Cavitands: Synthesis, Molecular Recognition, and Interactions with Phospholipid Membranes." ScholarWorks@UNO, 2012. http://scholarworks.uno.edu/td/1572.

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Water-soluble deep-cavity cavitands provide a rare opportunity to study self-assembly driven by the hydrophobic effect. These molecular hosts dimerize in the presence of certain guest molecules to form water-soluble molecular capsules. These systems have given rise to numerous novel chemical phenomena and have potential use in drug delivery. The host octaacid (OA) has been particularly well-characterized, but studies are limited to basic pH because of limited host solubility. Herein we report an improved synthesis of OA and the syntheses of three new water-soluble deep-cavity cavitands. The new hosts are soluble at neutral pH, increasing relevance for biological studies. The new syntheses are versatile enough to apply to the synthesis of additional water- soluble cavitands in the future. We also describe preliminary characterization of the molecular recognition properties of the new hosts. Binding of organic guest molecules to form 1:1 host:guest complexes and 2:1 host:guest capsules was qualitatively similar to that of OA. However, binding of anions spanning the Hofmeister series revealed interesting new behavior. The new hosts bound a wider range of anions inside the hydrophobic pocket with much higher association constants. Moreover, external binding of several anions to the cavitand pendant feet was observed. Looking towards biological applications, we desired to learn how these molecules interact with phospholipid membranes. Six water-soluble cavitands were tested for their ability to permeabilize liposomal POPC membranes. One host showed very high potency in permeabilizing membranes, while three other hosts showed moderate activity. Host binding of POPC was found to be at least one factor in host-induced permeabilization. A requenching assay to determine leakage mechanism strongly supported all-or-none leakage, whereby some vesicles lose all contents while others lose none. These results suggest that these cavitands induce partial transient leakage of vesicles by the formation of transient membrane pores. These findings show potential for the use of these hosts as drug delivery carriers, antimicrobial compounds, and tools in membrane alteration studies.

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Wood, Evan Alexander. "Designing hypercyclic replicating networks /." St Andrews, 2007. http://hdl.handle.net/10023/360.

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Spence, Graeme T. "Imidazolium- and triazolium-based interlocked structures for anion recognition and sensing." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:3de31ccf-db32-402c-b2b4-fca475500080.

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This thesis describes the synthesis and investigation of novel anion templated interlocked structures which incorporate the positively charged imidazolium and triazolium binding motifs for applications in anion recognition and sensing. Chapter One introduces the fields of anion supramolecular chemistry and mechanically interlocked structures, focusing on topics of particular relevance to this thesis, including anion recognition, anion sensing and the templated synthesis of interlocked architectures. Chapter Two details the incorporation of the imidazolium motif into the axle components of anion templated rotaxane hosts to achieve selective anion recognition by virtue of their interlocked binding cavities. The effects of exploiting imidazolium motifs with contrasting hydrogen bond donor arrangements and reducing the macrocycle size on the anion recognition properties of such systems were investigated using 1H NMR spectroscopy. Chapter Three reports the work undertaken to utilise fluorescent reporter groups as stoppers in the synthesis of anion sensing rotaxanes. Imidazolium- and triazolium based systems containing either luminescent ruthenium(II) bipyridyl complexes or the organic fluorophore anthracene were prepared and their anion sensing behaviours explored using fluorescence spectroscopy. Synthetic efforts to construct suitable photo-active rotaxanes are detailed. Chapter Four describes investigations of the novel naphthalimide triazolium motif both for use in interlocked molecular motion systems, and for fluorescence sensing applications. The preparation of a naphthalimide triazolium rotaxane, capable of selective, anion-induced, uni-directional shuttling which was investigated extensively using 1H NMR spectroscopy and optically signalled by perturbations in the UV/Vis spectrum, is detailed. Preliminary research studies into the potential to exploit this motif for surface based fluorescence sensing devices are also included. Chapter Five presents research into the utilisation of acyclic receptors displaying considerable binding induced conformational changes for fluorescence anion sensing. The recognition properties of a series of imidazolium-based receptors were studied, whilst the ability of a pyrene appended analogue to signal anion complexation via changes in excimer emission is reported. The control of interpenetrated assembly formation using anion-induced conformational changes within the threading component of a pseudorotaxane is also discussed. Chapter Six provides the experimental procedures and characterisation details for the compounds synthesised in this thesis. Chapter Seven is a summary of conclusions from Chapters Two, Three, Four and Five. Supplementary information relating to titration protocols, crystallographic data and surface studies is provided in the Appendices.

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Blom, Magnus. "Light-Triggered Conformational Switches for Modulation of Molecular Recognition : Applications for Peptidomimetics and Supramolecular Systems." Doctoral thesis, Uppsala universitet, Syntetisk organisk kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-267845.

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The main focus of this thesis is on photochemical modulation of molecular recognition in various host-guest systems. This involves the design, synthesis and integration of light-triggered conformational switches into peptidomimetic guests and molecular tweezer hosts. The impact of the switches on guest and host structures has been assessed by spectroscopic and computational conformational analysis. Effects of photochemical structure modulation on molecular recognition in protein-ligand and supramolecular host-guest systems are discussed. Phototriggerable peptidomimetic inhibitors of the enzyme M. tuberculosis ribonucleotide reductase (RNR) were obtained by incorporation of a stilbene based amino acid moiety into oligopeptides between 3-9 residues long (Paper I). Interstrand hydrogen bond probability in the E and Z forms of the peptidomimetics was used as a tool for predicting conformational preferences. Considerable differences in inhibitory potency for the E and Z photoisomers were demonstrated in a binding assay. In order to advance the concept of photomodulable inhibitors, synthetic routes towards amino acid derivatives based on the more rigid stiff-stilbene chromophore were developed (Paper II). The effect of E-Z isomerization on the conformational properties of peptidomimetic inhibitors incorporating the stiff-stilbene chromophore was also assessed computationally (Paper III). It was indicated that inhibitors with the more rigid amino acid derivative should display larger conformational divergence between photoisomers than corresponding stilbene derivatives. Bisporphyrin tweezers with enediyne and stiff-stilbene spacers have been synthesized, and the conformational characteristics imposed by the spacers have been studied and compared to a glycoluril linked tweezer. The effects of spacers on tweezer binding of diamine guests and helicity induction by chiral guests have been investigated (Paper IV). Connections between spacer flexibility and host-guest binding strength have been established. The structural properties of the stiff-stilbene spaced tweezer made it particularly susceptible to helicity induction by both monotopic and bitopic chiral guests. Finally, the possibility of photochemical bite-size variation of tweezers with photoswitchable spacers has been assessed. Initial studies have shown that photoisomerization of the tweezers is possible without photochemical decomposition. Conformational analyses indicate that isomerization should impact binding characteristics of the tweezers to a significant extent (Paper V).

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Persil, Cetinkol Ozgul. "Small molecule recognition of homopurine." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/29739.

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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009.
Committee Chair: Hud, Nicholas; Committee Member: Doyle, Donald; Committee Member: Lobachev, Kirill; Committee Member: Oyelere, Adegboyega; Committee Member: Wartell, Roger. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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Cougnon, Fabien B. L. "Dynamic combinatorial synthesis of donor-acceptor catenanes." Thesis, University of Cambridge, 2012. https://www.repository.cam.ac.uk/handle/1810/241659.

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Dynamic combinatorial chemistry (DCC) is a powerful method for synthesising complex molecules and identifying unexpected receptors. Chapter 1 gives an overview of the concept of DCC and its applications, and discusses its evolution to date. Chapter 2 describes the discovery of a new generation of donor-acceptor [2]catenanes in aqueous dynamic combinatorial systems. The assembly of these [2]catenanes is promoted by a high salt concentration (1 M NaNO3), which raises the ionic strength and encourages hydrophobic association. More importantly, a mechanism that explains and predicts the structures formed is proposed, giving a fundamental insight into the role played by hydrophobic effect and donor-acceptor interactions in this process. Building on these results, Chapter 3 describes the assembly in high salt aqueous libraries of a larger structure: a [3]catenane. Remarkably, the [3]catenane exhibits strong binding interactions with a biologically relevant target - spermine - in water under near-physiological conditions. Its synthesis is improved if the salt is replaced by a sub-mM concentration of spermine, acting as a template. Chapter 4 explores in further detail how subtle variations in the building block design influence the selective formation of either [2] or [3]catenanes. This last section underlines both the advantages and the limitations of the method developed in Chapter 3. After a short conclusion (Chapter 5), Chapter 6 gives experimental details.

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Mateus, Pedro Miguel Veríssimo. "Ditopic molecular architectures for the recognition of anionic species." Doctoral thesis, Universidade Nova de Lisboa. Instituto de Tecnologia Química e Biológica, 2011. http://hdl.handle.net/10362/6859.

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Dissertation presented to obtain the Ph.D degree in Chemistry
Anions are ubiquitous and very important species in biological, medicinal, industrial and environmental processes. In biology, anions are essential for normal metabolic functions, where their specific recognition, transport and detection play a very important role. On the other hand, the uncontrolled release of anions into the environment poses a significant threat. The development of synthetic receptors capable of sequestering anions should, therefore, provide solutions to a number of problems of current interest. To be suitable for real-life applications, as for instance the detection and quantification of biologically active anions in clinical laboratories or the environmental monitoring and/or removal of pollutants, synthetic receptors need to be able to function in aqueous solution. However, due to the high dielectric constant and good hydrogen bond donor and acceptor capabilities, water is the most challenging medium for anion recognition.(...)
The work described in this thesis was entirely carried out in Instituto de Tecnologia Química e Biológica, Oeiras, Portugal. Pedro Mateus has received financial support from Fundação para a Ciência e Tecnologia, ref. SFRH/BD/36159/2007.

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Peñuelas, Haro Guillem. "Towards Recognition of Polar Molecules in Water Using Calix[4]pyrrole Based Receptors." Doctoral thesis, Universitat Rovira i Virgili, 2020. http://hdl.handle.net/10803/670758.

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Aquesta tesi s’ocupa del disseny, síntesi i estudis d’unió de receptors amfifílics solubles en aigua per a la unió selectiva de molècules o residus polars neutres relacionats amb la salut humana. Amb aquesta finalitat, es van seleccionar receptors basats en calix[4]pirrol aril-estesos. Aquests andamis presenten una cavitat còncava tancada en un extrem per quatre grups polars (NHs de pirrol) i oberta al seu extrem oposat. Aquestes característiques permeten que les interaccions polars i no polars operin en sinergia per obtenir alts nivells d’afinitat i selectivitat. Específicament, es descriu el disseny, la síntesi i els estudis d’unió de tres generacions d’una nova família d’andamis calix[4]pirrols aril-estesos cavitats mitjançant grups fosfonat per a la unió selectiva de creatinina. Es descriuen les modificacions estructurals i les conclusions extretes de cada generació. Tot i que no es va aconseguir la selectivitat esperada, es van obtenir valors rellevants de constants d’unió per a alguns dels receptors estudiats (Ka ≈ 1000 M-1). Per a comprendre millor com funcionen aquests tipus de receptors en aigua, es va realitzar un estudi exhaustiu de les seves propietats d'unió utilitzant una sèrie d’hostes polars neutres. Els resultats derivats d’aquests estudis mostren que els receptors calix[4]pirrol son excel·lents amfitrions d’amides, urees i N-òxids de piridina en aigua, obtenint valors de constant d’unió majors que 100000 M-1. Es va demostrar que els receptors calix[4]pirrol són millors donadors d’enllaç d’hidrogen que l’aigua. També es descriu el disseny i la síntesi de dos nous receptors calix[4]pirrol amb tirants que presenten terminacions dendrítiques ionitzables per a la unió selectiva de monosacàrids. L’estratègia sintètica optimitzada es discuteix en detall. Es van realitzar estudis d’unió amb un dels receptors sintetitzats amb octil-D-glucòsid en medi orgànic. Els resultats extres d’aquests experiments representen un bon auguri per a la seva transferència a solució aquosa.
Esta tesis se ocupa del diseño, síntesis y estudios de unión de receptores anfifílicos solubles en agua para la unión selectiva de moléculas o residuos polares neutros relacionados con la salud humana. Con este fin, se seleccionaron receptores basados calix[4]pirrol aril-extendido. Estos andamios presentan una cavidad cóncava cerrada en un extremo por cuatro grupos polares (NHs de pirrol) y abiertos en su extremo opuesto. Estas características permiten que las interacciones polares y no polares operen sinérgicamente para obtener altos niveles de afinidad y selectividad. Específicamente, describimos el diseño, síntesis y estudios de unión de tres generaciones de una nueva familia de andamios calix[4]pirroles aril-extendidos cavitados mediante grupos fosfonato para la unión selectiva de creatinina. Se describen las modificaciones estructurales y las conclusiones extraídas de cada generación. Aunque no se logró la selectividad esperada, se obtuvieron valores relevantes de constantes de unión para algunos de los receptores estudiados (Ka ≈ 1000 M-1). Para comprender mejor cómo funcionan estos tipos de receptores en el agua, realizamos un estudio exhaustivo de sus propiedades de unión utilizando una serie de huéspedes neutros polares. Los resultados derivados de estos estudios mostraron que los receptores calix[4]pirrol son excelentes anfitriones de amidas, ureas y N-óxidos en agua, obteniendo valores de constante de unión mayores de 100000 M-1. Pudimos demostrar que los receptores calix[4]pirrol son mejores dadores de enlaces de hidrógeno que el agua. También describimos el diseño y la síntesis de dos nuevos receptores calix[4]pirrol con tirantes que presentan terminaciones dendríticas ionizables para la unión selectiva de monosacáridos. La estrategia sintética optimizada se discute en detalle. Realizamos estudios de unión con uno de los receptores sintetizados en medio orgánico con octil-D-glucósido. Los resultados extraídos de estos experimentos representan un buen augurio para su transferencia a solución acuosa.
This thesis deals with the design, synthesis and binding studies of water-soluble amphiphilic receptors for the selective binding of polar neutral molecules or residues related to human health. To do so, we selected aryl-extended calix[4]pyrrole based receptors. These scaffolds deliver a concave cavity closed at one end by four polar groups (pyrrole NHs) and opened at their opposite end. These features allow polar and non-polar interactions to operate synergistically to obtain high levels of affinity and selectivity. Specifically, we describe the design, synthesis and binding studies of three generations of a novel family of phosphonate cavitands based on aryl-extended calix[4]pyrrole scaffolds for the selective binding of creatinine. The structural modifications and the conclusions extracted from each generation are described. Although the expected selectivity was not accomplished, large binding constants were obtained for some of the studied receptors (Ka ≈ 1000 M-1). In order to better understand how these types of receptors function in water, we performed a thorough study of their binding properties using a series of polar neutral guests. The results derived from this studies showed that calix[4]pyrroles are excellent hosts for amides, ureas and N-oxides in water, reaching binding constant values larger than 100000 M-1. We could demonstrate that calix[4]pyrrole receptors are better hydrogen bonding donors than bulk water. We also report the design and synthesis of two novel strapped calix[4]pyrroles featuring ionizable dendritic terminations for the selective binding of mono-saccharides. The optimized synthetic strategy is discussed in detail. We performed binding studies with one of the synthesized receptors in organic media with octyl-D-glucoside. The extracted results from these experiments augur well for its transfer to aqueous solution.

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Thom, James Andrew. "Self-assembly and anion recognition with binuclear lanthanide complexes." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:20de876d-0a52-4f11-82b7-922fc3e2ee45.

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This work describes an investigation into the solution-phase binding of anionic guests by bimacrocyclic lanthanide complexes. It outlines the preparation of different classes of complexes bearing two metallic domains, and the effects of association on both the complex and the guest. Chapter one provides a cursory introduction to the fundamental properties of the lanthanides with a focus on luminescence. A brief literature review is given on the use of emissive lanthanide probes for the sensing of analytes. Chapter two concerns the preparation and properties of a series of binuclear complexes in which the two centres are linked with a short spacer group, with the aim of selectively sequestering small anions such as the halides in solution. The concept of luminescence titration will be introduced and then used to assess the binding parameters of a selection of guests. Chapter three describes a related class of ditopic lanthanide complexes in which the two metal centres are separated by a semi-rigid butyne linking group. Luminescence studies are again used to evaluate the binding constants of homologous series of dianions to ascertain how the size, geometry and functionalization of the anionic guest impacts on binding. Chapter four explores the coordination of phosphate species and assesses the ability to bind biologically significant phosphates of some of the complexes from Chapter 3. Chapter five details an investigation into the effects on guest-selectivity of further lengthening the linking unit which separates the two macrocyclic binding domains. Chapter six summarises the work done throughout the thesis and draws some overarching conclusions, as well as highlighting areas for further study. Chapter seven describes the experimental procedures.

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Evans, Nicholas Henley. "Redox-active rotaxanes and catenanes for anion sensing." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:6c1565b7-9ce9-46ec-97c5-3b2e3ed3b98a.

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This thesis is concerned with the synthesis and study of novel anion templated rotaxanes and catenanes for electrochemical anion sensing, as well as interlocked structures that possess different anion binding properties, higher-order topologies and the ability to undergo molecular motion. Chapter One provides an introduction to anion recognition and the preparation of interlocked structures. A short summary of fundamental aspects of supramolecular chemistry is followed by detailed surveys of current approaches to anion binding and sensing, as well as the templated synthesis of rotaxanes and catenanes. Chapter Two describes the preparation of rotaxanes and catenanes appended with ferrocene to allow for electrochemical anion sensing. The anion recognition properties of a [2]rotaxane and a [2]catenane, as investigated by ¹H NMR spectroscopy and electrochemical methods, are presented. The utilization of a ferrocene-appended macrocycle in the construction of surface confined anion templated rotaxanes and catenanes is also discussed. Chapter Three reports the work carried out to achieve electrochemical anion sensing by the incorporation of redox-active groups into the integral structures of interlocked structures. The syntheses of a bis-stoppered 1, 2, 3, 4, 5-pentaphenylferrocene [2]rotaxane and a ferrocene containing [3]rotaxane are presented, along with their subsequent anion recognition studies. In addition, attempts to incorporate ferrocene into the macrocyclic components of rotaxanes and catenanes are outlined. Chapter Four details further investigations into the use of interlocked structures to achieve anion recognition. Doubly-charged [2]catenanes able to bind anions in aqueous solvent media, as well as the incorporation of alternative anion binding motifs into interlocked architectures are reported. The exploitation of anion templated synthesis to allow for the construction of higher order structures (including [3]catenanes, a “handcuff” catenane and a Janus [2]rotaxane), as well as a [2]catenane system with anion controlled molecular motion is also described. Chapter Five presents the experimental procedures and characterization data relating to the compounds prepared in Chapters Two, Three and Four. Chapter Six summarizes the main conclusions of the work contained within this thesis. Supplementary experimental information relating to titration protocols, investigations into self-assembled monolayers (SAMs) and crystallographic data are provided in Appendices I, II and III.

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Berryman, Orion Boyd 1981. "Anions and electron-deficient aromatic rings." Thesis, University of Oregon, 2008. http://hdl.handle.net/1794/8159.

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xx, 281 p. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.
More than two-thirds of all enzyme substrates and cofactors are anionic, emphasizing the essential role that anions play in biological processes. Moreover, anions can have detrimental effects on the environment by causing ground water contamination when anions such as perchlorate, phosphate and nitrate develop in intolerable levels. Owing to the prevalent nature of anions, traditional strategies employed to target anions--including hydrogen bonding, metal ion coordination and electrostatic interactions--have been extensively studied. An alternative approach to anion binding would complement the powerful array of existing techniques. Recently, in the supramolecular chemistry community, new insight has been cast on how anions attractively interact with electron-deficient arenes, suggesting that aromatic rings are a viable anion binding strategy to balance existing methods. Chapter I provides a historical perspective of anions interacting with electron- deficient arenes. This outlook has its origins in the late 1800s with the discovery of colored charge-transfer complexes between donor and acceptor molecules and continues with the progression of the field leading up to the recent supramolecular fascination. Chapter II represents our initial efforts at measuring anion/arene interactions in solution. In particular, sulfonamide based hydrogen bonding receptors were developed with pendant aromatic rings to test the strength of anion/arene interactions in solution. Complementary computational chemistry and crystallography were utilized to supplement the solution studies. Chapter III describes our quantum calculations and crystallographic efforts at using only electron-deficient arenes to bind halides. A Cambridge Structure Database survey supports our emphasis of understanding multiple anion/arene interactions. Chapter IV illustrates how tripodal anion receptors can be developed to bind anions using only electron-deficient aromatic rings. Furthermore, subtle changes in anion binding geometries are observed with isomeric receptors and corroborated with Density Functional Theory calculations. Chapter V is dedicated to the preparation of electron-deficient anion receptors that are conformationally stabilized by hydrogen bonds. Chapter VI is committed to using our knowledge of anion binding to study a series of ethynyl-pyridine sulfonamides capable of hydrogen bonding to small molecules and anions. In conclusion, Chapter VII is a summary and future prospective for the field of anion/arene interactions. This dissertation includes previously published and co-authored material.
Adviser: Darren W. Johnson

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Wood, Evan A. "Designing hypercyclic replicating networks." Thesis, University of St Andrews, 2007. http://hdl.handle.net/10023/360.

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In the last 20 years there has been a number of synthetic and natural product based molecular replicators published in the literature. The majority of these systems have focused on the minimal model with only a few examples of cross-catalytic or reciprocal replication. Of the cross-catalytic systems investigated the majority focus around the use of natural products, oligonucleotides, peptides etc. This thesis will investigate the design, synthesis and kinetic analysis of both synthetic minimal and reciprocal replicating systems, and how these two forms of replication interact in a complex hypercyclic network. Chapter 1 introduces key concepts such as molecular recognition, intramolecularity/ enzyme kinetic, bisubstrate systems and the work conducted into replication systems to date. Chapter 2 describes the design, synthesis and kinetic analysis of a reciprocal replicating system, based on Diels-Alder and 1,3-dipolar cycloadditions, before going on to discuss what we have learned and how this system can be improved. Chapter 3 focuses on the design, synthesis and kinetic analysis of a replicating network (minimal and reciprocal replication), based on 1,3-dipolar cycloadditions. Initial individual systems are examined in isolation to determine their behavior and nature. After which the systems are combined to observe how each species interacts in a potential complex hypercyclic network. Chapter 4 investigates the redesign of the replicating network in Chapter 3 in order to overcome the problems identified from its kinetic analysis. Chapter 5 introduces the shift in direction away from kinetically controlled replicating networks towards systems in thermodynamic equilibrium.

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Langton, Matthew J. "Interlocked host structures for anion recognition and sensing in aqueous solutions." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:11bd6ac1-f340-47af-9081-5598c0036861.

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This thesis describes the synthesis of interlocked anion host systems which exploit hydrogen bonding, halogen bonding, and lanthanide-coordination for anion recognition and sensing in aqueous solution. Chapter 1 introduces the field of anion supramolecular chemistry, with particular focus on areas of particular relevance to this thesis, namely anion recognition and sensing, anion templation and the synthesis of interlocked structures. Chapter 2 describes the synthesis of hydrogen bonding rotaxane and catenane hosts for recognising and sensing oxoanions in aqueous solvent media. The novel use of nitrate anion templation for the synthesis of interlocked molecules is reported, and the unprecedented selective recognition of nitrate in aqueous solvent media is demonstrated. Chapter 3 details the preparation of water soluble permethylated β-cyclodextrin-stoppered rotaxane hosts that utilise halogen bonding and hydrogen bonding interactions to bind anions in pure water. The first thermodynamic investigation into halogen bonding in water is reported, and the relative capabilities of halogen and hydrogen bonding for anion recognition in water are compared. Chapter 4 investigates the incorporation of lanthanide cations into rotaxane hosts for optical anion sensing. The seminal use of lanthanide cation templation for interlocked molecule synthesis is described, before anion templation approaches towards the synthesis of lanthanide-based rotaxanes are discussed. The luminescence anion sensing capabilities of these interlocked hosts are investigated. Chapter 5 describes the experimental procedures used in this work, and details the characterisation of compounds presented in Chapters 2–4. Chapter 6 summarises the conclusions of this thesis.

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Llorens, Palomo Lluís. "Preparation of CBs immobilized on different types of magnetic nanoparticles for application in selective complexation and catalysis." Doctoral thesis, Universitat de Barcelona, 2019. http://hdl.handle.net/10803/667877.

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Cucurbiturils are known to present potential applications in molecular recognition, self- assembly, and nanotechnology. The discovery of ultra-high affinity CB–guest complexes with binding constant values similar than those found in natural complexes beckoned the attention of many groups, that focused their research in the functionalization of cucurbiturils in order to modify their structure and properties, to enhance their solubility, and to provide different functional groups for further transformations. In fact, cucurbiturils have been supported onto different solid surfaces such as gold surface, polymer beads, or nanoparticles. Iron is a bioactive metal with magnetic properties and low toxicity to mammalian cells. The formation of 10 nm magnetic nanoparticles (MNPs) of iron oxide (Fe3O4) can be achieved in an affordable and easily reproducible manner by thermal decomposition. This small size of nanoparticles provides a double advantage: first, biodegradability, because particles up to 100 nm can be phagocytosed through liver cells; second, superparamagnetic behavior, so that they become magnetized upon exposure to a magnetic field but have no permanent magnetization once the field is turned off. Prompted by the breadth of possible applications provided by cucurbiturils and our previous experience immobilizing organic molecules on MNPs of Fe3O4 and polystyrene resin (PR) (generally, to covalently immobilize catalysts for the preparation of easily recoverable and recyclable catalysts), we speculated that covalently attached cucurbiturils onto MNPs could open up new routes concerning drug delivery and biocatalysis, enable applications in many areas including sensor, transport, separation, and nanomaterials. Hence, the first research project included in this dissertation (chapter II), unveils the development of polystyrene and magnetic nanoparticles coated with a cucurbituril layer. The intrinsic properties of these compounds have been tested on the extraction of selected molecules (guests that bind to cucurbiturils). Also, in this chapter, the preparation and characterization of a library of these novel compounds—that exhibit a potential use in molecular recognition, transport, and separation—is described. The second project, described in chapter III, illustrates the synthesis of catalysts tagged with an adamantyl moiety to enhance their affinity towards cucurbiturils—for their selective extraction from the reaction media. This is achieved by covalent linking of the cucurbituril receptor to the superparamagnetic Fe3O4 nanoparticles to allow magnetic decantation. These compounds were prepared, and their catalytic activity and reusability were tested: first, on the model aldol reaction between ketones and benzaldehydes; secondly, on the enantioselective Robinson annulation with the well-established Wieland-Miescher ketone. Chapter IV showcases the preparation of a quaternary amino derivatizing reagent decorated with an adamantyl moiety. This reagent reacts with ketone-containing steroids such as testosterone. Upon reaction, the resulting derivative can be selectively extracted from the solution mixture and driven away by the magnetically powered nanoparticles. Finally, chapter V provides some computational insights on the nature and the strength of the cucurbit[7]uril interactions with some adamantyl-based guests. The studies are built on novel and unprecedented computational models able to reproduce experimental procedures on the determination of enthalpic and entropic changes. Therefore, the main goal of the present thesis is the development of novel magnetically powered nanodevices for the efficient and selective extraction of chemical cargos. Supramolecular chemistry—especial emphasis on cucurbiturils—will play a central lead in this manuscript due to the endogenous chemical properties of the supramolecules, and the robust and modulable nature of their guests. Moreover, we will cover the entire manufacture of the nanodevices or chemical shuttles, their potential use in asymmetric catalysis, and their applicability in molecular recognition and enrichment.
El primer projecte de recerca, inclòs al capítol II, revela el desenvolupament de poliestirè i nanopartícules magnètiques recobertes amb una capa de cucurbituril. Durant aquesta secció, s’han provat les propietats intrínseques d’aquests compostos per a l’extracció de molècules seleccionades (hostes) que s’uneixen als cucurbiturils. A més, en aquest capítol, s’ha fet un esforç per caracteritzar amb precisió una varietat d’aquests nous compostos que presenten un potencial ús en el reconeixement molecular, el transport i la separació. El segon projecte, descrit al capítol III, il·lustra la síntesi de catalitzadors etiquetats amb un fragment adamantil per millorar la seva afinitat cap als cucurbiturils, i promoure la seva extracció selectiva. Això s’aconsegueix per mitjà de l’enllaç covalent entre el receptor de cucurbituril i les nanopartícules superparamagnètiques (Fe3O4), que permetent la decantació magnètica del sistema format. Una varietat d’aquests compostos s’ha preparat, i la seva activitat catalítica així com la reutilitzabilitat s’han posat també a prova: primer, en la reacció aldòlica entre cetones i benzaldehids; després, en la reacció enantioselectiva de Robinson, amb la ben consolidada cetona de Wieland i Miescher. Al capítol IV es mostra la preparació d’un reactiu derivatitzant que inclou una amina quaternària i un grup adamantil. Aquesta molècula presenta reactivitat amb esteroides que contenen cetones com la testosterona. Després de reaccionar, el derivat resultant es pot extreure selectivament de la barreja de solució i desplaçar-lo a parer, fent ús de les propietats magnètiques de les nanopartícules. Finalment, el capítol V aporta unes idees sobre la naturalesa i força de les interaccions entre els cucurbiturils i uns determinats hostes, basant-nos en uns models computacionals innovadors i sense precedents que són capaços de reproduir resultats experimentals per a la determinació de canvis entàlpics i entròpics.

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Chu, Cheng-Che. "Hydrogen-bonded supramolecular materials for organic photovoltaic applications." Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13866/document.

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Dans ce manuscrit est décrite l'utilisation d'interactions supramoléculaires pour diriger l'auto-assemblage de composés donneurs et accepteurs d'électrons au sein de dispositifs photovoltaïques organiques. Dans ce but, des matériaux de type oligo-3-hexylthiophène et fullerène ont été fonctionnalisés avec des groupements de reconnaissance complémentaires mélamine – acide barbiturique. La présence de élements solubilisants confère à ces composés une bonne mise en oeuvre permettant la fabrication de dispositifs photovoltaïques à hétérojonction volumique. L'effet de la composition et du post-traitement de la couche active sur la performance de ces dispositifs ont été explorés. Les études de mobilité de charge et des mécanismes de recombinaison au sein de ces matériaux indiquent que l'équilibre entre auto-association et séparation de phases est crucial pour l'efficacité en conversion photovoltaïque
This research aims to elucidate the use of supramolecular interaction to guide the formation of well-defined nanoscale self-assembled architecture in photovoltaic solar cells as a means to improve device efficiency. Complementary molecular recognition sites based on melamine and barbituric acid were used to obtain functionalized fullerene and oligothiophene materials with superior processibility thanks to the presence of specific solubilizing groups. The efficiency of solid-state devices fabricated using the bulk heterojunction design was studied with respect to device morphology and composition. Experiments on recombination mechanism and field effect mobilities suggest that the balance between hydrogen-bonding interactions induce self-assembly and p-p interactions to promote phase segregation is crucial to the micro-structure of the active layer. The investigated of the relationship between the oligothiophene chain size and various complementary hydrogen-bonding motifs is envisaged

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Cornut, Damien. "Synthèse et étude des propriétés hôte-invité de récepteurs hétéroditopiques de type calix[6]crypt-(thio)urée." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209159.

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La chimie supramoléculaire est un domaine qui porte sur l’étude des interactions

faibles entre molécules. Ces interactions sont très répandues dans les systèmes naturels et de

nombreux récepteurs moléculaires synthétiques ont été développés, soit pour un apport

théorique à la compréhension de ces processus de reconnaissance, soit pour d’éventuelles

applications en biologie ou en chimie analytique par exemple.

Les calix[6]arènes sont des composés intéressants pour la reconnaissance moléculaire.

Ils possèdent une cavité idéale pour l’inclusion de petites molécules et peuvent être modifiés

par l’ajout de divers motifs de reconnaissance. Le premier calix[6]crypturée préalablement

étudié au sein du Laboratoire de Chimie Organique est un récepteur dont la cavité aromatique

est juxtaposée à un motif de reconnaissance pour anions. Ce dernier est composé d’un

chapeau à base de tren (tris(2-aminoéthyl)amine) portant trois groupes urée. Ce récepteur

possède notamment une forte sélectivité pour le chlorure et une forte affinité pour les paires

d’ions organiques de type chlorure d’ammonium, dans un solvant apolaire (CDCl3).

Cependant, ces propriétés de reconnaissance sont beaucoup plus limitées dans un solvant

protique (CD3OD), ce qui restreint les éventuelles applications. L’objectif de ces travaux a été

de synthétiser de nouveaux dérivés avec une modification autour du site tris-urée pour

renforcer les propriétés de reconnaissance, notamment en milieu protique.

La première stratégie a consisté à agrandir le chapeau cryptant reliant les trois groupes

urée. Trois modes différents de complexation d’ammonium intra-cavitaire ont été mis en

évidence dans un solvant apolaire, dont deux sont remarquables. Avec un anion peu

coordinant (le picrate), le récepteur protoné inclut l’ammonium selon un processus

allostérique pour donner un complexe dicationique. Avec la protonation du récepteur et un

anion dichargé (SO4

2-), l’inclusion de l’ammonium constitue un complexe cascade, stable en

milieu protique.

La deuxième stratégie a consisté à supprimer les groupes méthyle du petit col

calixarénique via une réaction de déméthylation sélective pour obtenir le calix[6]crypturée

1,3,5-trishydroxyle. Dans un solvant apolaire, ce récepteur a montré une plus forte sélectivité

pour la complexation de paires d’ions par rapport à la complexation d’anions, permettant par

exemple de complexer le chlorhydrate de O,O-diméthyldopamine.

La troisième stratégie a été de synthétiser le calix[6]cryptothiourée, un récepteur dont

le chapeau comporte trois groupes thiourée. Cette modification structurale a fortement

renforcé la complexation d’anions mais n’a pas favorisé la complexation de paires d’ions dans

un solvant protique.

Enfin, la complexation de zwittérions a été testée sur l’ensemble de ces récepteurs et le

calix[6]cryptothiourée s’est avéré être un remarquable complexant de la B-alanine bétaïne.

Dans un mélange protique (CD3OD/CDCl3 1:1) la constante d’association est élevée (K ≈ 104

M-1) et supérieure d’au moins trois ordres de grandeur par rapport aux autres zwittérions

testés. C’est à notre connaissance un des rares récepteurs de bétaïnes et le premier à être

sélectif pour la B-alanine bétaïne. Enfin, le biomimétisme du mode de reconnaissance a été

montré par comparaison avec une protéine transporteur de bétaïne (Corynebacterium

glutamicum).
Doctorat en sciences, Spécialisation chimie
info:eu-repo/semantics/nonPublished

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El, Sayed Shehata Nasr Sameh. "Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules." Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/52598.

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[EN] Abstract The present PhD thesis entitled "Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules" is based on the application of supramolecular chemistry and material science principles for the development of optical chemosensors for anions and neutral molecules detection. The second chapter of this PhD thesis is devoted to the preparation of chemodosimeters for the chromo-fluorogenic detection of fluoride, diisopropyl fluorophosphates (DFP) and hydrogen sulfide. The optical detection of fluoride anion was achieved by using a pyridine derivative containing a t-butyldimethylsilyl ether group. Aqueous solutions of the chemodosimeter were colorless but turned yellow upon addition of fluoride anion. Also a remarkable enhancement in emission was observed only upon the addition of fluoride. The optical changes were ascribed to a fluoride-induced hydrolysis of the silyl ether moiety. Also a chemodosimeter for the optical recognition of DFP, a nerve agent simulant, was prepared. In this case, the chemodosimeter was based on a stilbene pyridinium derivative functionalized with hydroxyl and silyl ether moieties. Aqueous solutions of the chemodosimeter were colorless changing to yellow upon DFP addition. The optical changes were ascribed to a hydroxyl phosphorylation followed by a fluoride-induced hydrolysis of the silyl ether group. Besides, that probe was implemented in test strips and DFP detection in gas phase was accomplished. Finally, the fluorogenic recognition of hydrogen sulfide anion was explored. For this purpose different fluorophores were selected and fucntionalized with 2,4-dinitrophenyl ether groups. The prepared probes were neraly non-emissive but remarkable emission enhancements upon addition of hydrogen sulfide were observed. The emission enhancements observed were due to a selective sulfide-induced hydrolysis of the 2,4-dinitrophenyl ether moiety that yielded the free fluorophores. Another set of chemodosimeters equipped with azide and sulfonylazide moieties were prepared. Again these probes were non-fluorescent but upon addition of hydrogen sulfide an important enhancement in emission was found. The selective response was ascribed to a reduction of the azide and sulfonylazide moieties to amine and sulfonylamide induced by hydrogen sulfide anion. Besides, the viability assays showed that these dosimeters were essentially non-toxic and real-time fluorescence imaging measurements confirmed their ability to detect intracellular hydrogen sulfide at micromolar concentrations. The third chapter of this PhD thesis was devoted to the preparation of nanoscopic gated materials and their use in sensing protocols. In a first step a gated material for the optical detection of glutathione (GSH) was prepared. For this purpose MCM-41 mesoporous silca nanoparticles were selected as inorganic scaffold. The pores were loaded with safranine O and the external surface was functionalized with disulfide-containing oligo(ethylene glycol) moieties. Dye delivery from aqueous suspensions of the sensory material was only observed in the presence of GSH. The signalling paradigm was ascribed to the selective reduction of the disulfide bond by GSH which induced pore opening and dye release. Also capped organic-inorganic hybrid materials for the selective detection of hydrogen sulfide were prepared and characterized. In this case the same MCM-41 support was used and charged with [Ru(bipy)3]2+ dye. Then, the external surface was functionalized with Cu(II)-macorcyclic complexes and finally, the pores were capped by the addition of the bulky anion hexametaphosphate. Aqueous suspensions of this material showed negligible dye release whereas in the presence of hydrogen sulfide anion a remarkable colour change was observed. This optical response was ascribed to a demetallation process of the Cu(II) complex induced by hydrogen sulfide.
[ES] Resumen La presente tesis doctoral titulada "Química supramolecular: Nuevos dosímetros químicos y materiales híbridos para la detección cromo-fluorogénica de aniones y moléculas neutras." está basada en la aplicación de principios básicos de la química supramolecular y de la ciencia de materiales en el desarrollo de sensores ópticos para aniones y moléculas neutras. El segundo capítulo de esta tesis doctoral está dedicado a la preparación de dosímetros químicos para la detección cromo-fluorogénica de fluoruro, diisopropil fluorofosfato (DFP) y sulfuro de hidrógeno. Para la detección óptica del anión fluoruro se sintetizó un derivado de piridina funcionalizado con un t-butildimetilsilil éter. En este capítulo también se describe la preparación de un dosímetro químico para la detección de DFP, que es un simulante de agentes nerviosos. Este dosímetro está basado en un estilbeno funcionalizado con una sal de piridinio que contiene grupos hidroxilo y silil éter en su estructura. Finalmente se prepararon dos familias de sensores para la detección óptica de hidrógeno sulfuro. La primera familia de sensores consiste en fluoróforos comunes funcionalizados con 2,4-dinitrofenil éteres. Los sensores preparados no presentaron una emisión de fluorescencia importante mientras que, en presencia del anión hidrógeno sulfuro, se observó un aumento significativo. La segunda familia de dosímetros también estaba compuesta por ciertos fluorofóros pero, en este caso, funcionalizados con grupos azida y sulfonilazida. Los dosimétros preparados, siguiendo esta segunda aproximación, tampoco dieron una fluorescencia significativa observándose un aumento de la misma al añadir el anión hidrógeno sulfuro. El tercer capítulo de esta tesis doctoral está dedicado a la preparación de materiales híbridos nanoscópicos funcionalizados con puertas moleculares y su aplicación en protocolos de reconocimiento. En primer lugar se preparó un material para la detección óptica de glutatión (GSH). Para ello se emplearon nanopartículas de MCM-41 mesoporosas como soporte inorgánico. Los poros del soporte fueron cargados con el colorante safranina O y la superficie externa funcionalizada con oligo(etilenglicol) conteniendo enlaces disulfuro. También se prepararon y caracterizaron varios materiales híbridos para la detección selectiva del anión hidrógeno sulfuro. En este caso también se empleó, como soporte inorgánico, sílice mesoporosa MCM-41. Los poros del soporte inorgánico fueron cargados con [Ru(bipy)3]2+ y la superficie externa funcionalizada con varios complejos macrocíclicos de Cu(II). El material sensor final fue obtenido al añadir el anion hexametafosfato, que compleja con los complejos de Cu(II), produciendo un bloqueo de los poros.
[CAT] Resum La present tesi doctoral titulada "Química supramolecular: Nous dosímetres químics i materials híbrids per a la detecció cromo-fluorogènica d'anions i molècules neutres." està basada en l'aplicació dels principis bàsics de la química supramolecular i de la ciència dels materials en el desenvolupament de sensors òptics per a anions i molècules neutres. El segon capítol d'aquesta tesi doctoral està dedicat a la preparació de dosímetres químics per a la detecció cromo-fluorogènica de fluorur, diisopropil fluorofosfat (DFP) i sulfur d'hidrogen. Per a la detecció òptica de l'anió fluorur es va sintetitzar un derivat de piridina funcionalitzat amb un t-dibutildimetilsilil èter. En aquest capítol també es descriu la preparació d'un dosímetre químic per a la detecció de DFP, que és un simulant d'agents nerviosos. Aquest dosímetre està basat en un estilbè funcionalitzat amb una sal de piridina que conté grups hidroxil i silis èter en la seua estructura. Finalment varen ser preparades dues famílies de sensors per a la detecció òptica de sulfur d'hidrogen. La primera família consisteix en fluoròfors comuns funcionalitzats amb 2,4-dinitrofenil èters. Els sensors preparats no presentaren una emissió de fluorescència significativa mentre que, en presencia de l'anió hidrogen sulfur, es va observar un augment significatiu. La segona família de dosímetres també estava composada per certs fluròfors però, en aquest cas, funcionalitzats amb grups azida i sulfonilazida. Els dosímetres preparats, seguint aquesta segona aproximació, tampoc donaren una fluorescència significativa observant-se un augment de la mateixa al afegir l'anió hidrogen sulfur. El tercer capítol d'aquesta tesi doctoral està dedicat a la preparació de materials híbrids nanoscòpics funcionalitzats amb portes moleculars i la seua aplicació en protocols de reconeixement. En primer lloc es va preparar un material per a la detecció òptica de glutatió (GSH). Per a aquest propòsit es varen emprar nanopartícules MCM-41 mesoporoses com a suport inorgànic. Els porus del suport varen ser carregats amb el colorant safranina O i la superfície externa funcionalitzada amb oligo(etilenglicol) que contenia enllaços disulfurs. També varen ser preparats i caracteritzats diversos materials híbrids per a la detecció selectiva de l'anió hidrogen sulfur. En aquest cas també es va emprar, com a suport inorgànic, sílice mesoporosa MCM-41. Els porus del suport inorgànic varen ser carregats amb [Ru(bipy)3]2+ i la superfície externa funcionalitzada amb diversos complexos macrocíclics de Cu(II). El material sensor final es va obtindre al afegir l'anió hexametafosfat, que es complexa amb macrocicles de Cu(II), produint un bloqueig dels porus.
El Sayed Shehata Nasr, S. (2015). Supramolecular Chemistry: New chemodosimeters and hybrid materials for the chromo-fluorogenic detection of anions and neutral molecules [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/52598
TESIS

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32

Valderrey, Berciano Virginia. "Calix[4]pyrrole and porphyrin-based molecular assemblies." Doctoral thesis, Universitat Rovira i Virgili, 2013. http://hdl.handle.net/10803/284092.

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Esta tesis se centra en el estudio de ensamblajes moleculares de calix[4]pirroles y porfirinas. Las propiedades de interacción y la topología de un bis-calix[4]pirrol macrotriciclo homoditópico han sido empleadas en el desarrollo de tres estrategias generales para el ensamblaje cuantitativo de pseudorotaxanos. En una de estas estrategias, el anión poliatómico de un par iónico es reconocido por el complejo supramolecular que resulta cuando una molécula lineal y neutra enhebra el macrotriciclo. Además, se describe la formación de complejos de dímeros de pares de iones y cuartetes de iones reconocidos por el macrotriciclo a través de un proceso altamente cooperativo. También, se estudia el reconocimiento de sales de tetrabutilamonio derivadas de fullerenos utilizando pinzas moleculares de porfirinas. Finalmente, se describe la formación de un macrociclo formado por la interacción de bisporfirinas de rodio y bispiridinas. Este macrociclo es usado en la formación de complejos con topología de rotaxano y pseudorotaxano.
This thesis is focused on the study of molecular assemblies based on calix[4]pyrroles and porphyrins. The topology and the binding properties of a homoditopic biscalix[4]pyrrole macrotricycle are used to develop three general strategies for the quantitative self-assembly of pseudorotaxane-like complexes. In one strategy, the polyatomic anion of an ion pair is recognized by the supramolecular complex that results when a neutral linear molecule threads the homoditopic macrotricycle. Additionally, the formation of highly stable complexes of ion-pair dimers and quartets of ions by the bis-calix[4]pyrrole receptor through a highly cooperative process is described. Nickel metallated porphyrin tweezers containing calix[4]pyrrole spacers are used in the recognition of the tetrabutylammonium salt of the [6,6]-phenyl-C61-butyric carboxylic acid. Finally, the quantitative self-assembly of a macrocycle formed by the interaction between a rhodium bisporphyrin and a bispyridyl ligand is described. This macrocycle was used in the formation of complexes with [2]pseudorotaxane and [2]rotaxane-like topologies.

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33

Lascaux, Angélique. "Synthèse et étude de nouveaux récepteurs ditopiques fonctionnalisés dérivés de calix[6]arènes: des calix[6]cryptamides aux calix[6]trens." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209473.

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Ce travail s'inscrit dans le cadre de la chimie supramoléculaire, domaine s'intéressant à l'étude d'édifices moléculaires liés par des interactions non-covalentes, fréquemment rencontrés dans le monde du vivant. Afin de mieux comprendre les phénomènes de complexation, de nombreux récepteurs moléculaires synthétiques ont été développés depuis ces cinquante dernières années. Dans le cadre de la reconnaissance moléculaire, les calix[6]arènes s'avèrent être des plateformes idéales puisqu'ils sont aisément fonctionnalisables et possèdent une cavité hydrophobe propice à l'inclusion de petites molécules organiques. D'ailleurs de nombreux récepteurs calix[6]aréniques ont déjà été développés et ont été étudiés pour leur aptitude à complexer des molécules neutres, des anions, des paires d'ions ou des ions métalliques. Cependant, ils souffrent de certaines limitations puisqu'ils ne sont pas hydrosolubles et sont difficilement post-fonctionnalisables limitant de ce fait leur applicabilité. Nous nous sommes donc intéressés à la synthèse de récepteurs calix[6]aréniques fonctionnalisés ainsi qu'à l'étude de leurs propriétés réceptrices vis-à-vis d'entités chargées ou de molécules neutres. Les études de ces systèmes ont été réalisées essentiellement par spectroscopie de Résonance Magnétique Nucléaire (RMN).

Dans le cadre de ce travail, des récepteurs ditopiques mono- et trisfonctionnalisés de type calix[6]cryptamide ont tout d'abord été développés. Ces récepteurs présentent un motif trenamide qui constitue un second site de reconnaissance, distinct mais proche du premier formé par la cavité calix[6]arénique. Ces récepteurs se sont révélés capables de complexer les molécules neutres polaires ainsi que des entités chargées avec une grande sélectivité en milieu aprotique mais également en présence d'un solvant protique. Le chapeau trenamide étant relativement contraint et bien préorganisé, il assure un fort effet chélate et permet une sélectivité de taille pour l'anion fluorure. La proximité des deux sites de reconnaissance ainsi que la sélectivité pour l'anion fluorure permettent à ces récepteurs de reconnaître des ammoniums sous forme de paires d'ions de contact uniquement avec le fluorure comme partenaire anionique. Les résultats obtenus ont démontré que l'introduction de fonctionnalisations soit au niveau du chapeau trenamide, à proximité du site de reconnaissance, soit au niveau du petit col du calix[6]arène n'inhibait pas les propriétés de complexation de ces récepteurs. Les premiers essais d'introduction de groupes hydrosolubilisants ont alors été réalisés et se sont révélés très prometteurs. En effet, l'introduction de groupements PEG sur un calix[6]cryptamide trisfonctionnalisé a permis de démontrer l'aptitude de ce récepteur à complexer des molécules neutres en milieu aqueux (CD3OD/D2O).

Dans un second temps, des récepteurs mono- et trisfonctionnalisés de type calix[6]tren ont été développés. Les études préliminaires réalisées ont permis de mettre en évidence que, comme le calix[6]tren non fonctionnalisé, ces récepteurs étaient capable de complexer de petites molécules organiques lorsqu'ils sont polarisés, soit sous leur forme per-protonnée soit sous la forme d'un complexe métallique (Zn2+ ou Cun+).

L'ensemble de ces travaux a ainsi permis de valider la stratégie de synthèse visant à introduire des bras fonctionnels sur des récepteurs ditopiques calix[6]aréniques et de démontrer que ces nouveaux récepteurs fonctionnalisés conservaient des propriétés de reconnaissance. Ces travaux permettent donc d'envisager de multiples applications pour ce type de récepteurs.

This work falls within the field of supramolecular chemistry, a field concerned with the study of molecular structures linked by non-covalent interactions. Such weak interactions are frequently encountered in the living world and in particular in molecular recognition processes. In order to better understand and exploit these recognition processes, many synthetic molecular receptors have been developed over the last fifty years. In this regard, calix[6]arenes have proved to be ideal platforms because they can be easily functionalized and they possess a hydrophobic cavity suitable for the inclusion of small organic molecules. Hence, many calix[6]arene based receptors have been studied for their ability to complex neutral molecules, anions, ion pairs or metal ions. However, most of these receptors suffer from major limitations that limit their applicability: they are not water soluble and hardly post-functionalizable. In the frame of this thesis, we were therefore interested in the synthesis of functionalized calix[6]arene based receptors and in the study of their host-guest properties toward charged species or neutral molecules. Studies of these host-guest systems have been carried out mainly by Nuclear Magnetic Resonance spectroscopy (NMR).

First, mono- and trisfunctionalized ditopic receptors based on a calix[6]cryptamide skeleton were synthesized. These receptors possess two binding sites in close proximity: a trenamide subunit and the calix[6]arene cavity. They have proved to be capable of complexing neutral polar molecules as well as charged species with high selectivity in aprotic solvents but also in a protic environment. The trenamide cap being relatively constrained and well pre-organized, it provides a strong chelate effect and allows a selectivity of size for the fluoride anion. Remarkably, the proximity of the two recognition sites allow these receptors to recognize ammonium ions in the form of contact ion pairs but only with a fluoride anion as the partner. The results have shown that the introduction of functionalizations at the trenamide cap or at the narrow rim of the calix[6]arene do not inhibit the complexation properties of these receptors. First attempts in order to introduce water-solubilizing groups have been undertaken and promising results have been obtained. Indeed, the introduction of PEG groups on a trisfunctionalized calix[6]cryptamide has led to a receptor able to complex neutral molecules in an aqueous environment (CD3OD/D2O).

In a second step, mono- and trisfunctionalized receptors derived from calix[6]tren have been synthesized. Preliminary studies have highlighted that, similarly to the parent calix[6]tren, these receptors are able to complex small organic molecules when they are polarized either in their per-protonated form or in the form of a metal complex (Zn2+ or Cun+).

All this work validates the synthetic strategy that consists of introducing functional arms on ditopic calix[6]arene based receptors and opens new perspectives for the elaboration and study of molecular receptors in an aqueous environment.

Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Romuald, Camille. "Des Muscles Moléculaires dans tous leurs Etats aux Noeuds Moléculaires inédits à Cavité Modulable." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20167.

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Cette thèse est dédiée à la conception de machines moléculaires pH-sensibles inédites de type muscles et nœuds moléculaires. Le premier muscle moléculaire pH-sensible a été synthétisé de manière très directe, et publié en 2008, en utilisant une stratégie en deux étapes: 1) fermeture des axes encapsulés par cycloaddition 1,3-dipolaire de type Huisgen catalysée par le cuivre (I), 2) méthylation des triazoles formés en triazoliums, capables d'être reconnus par les macrocycles DB24C8. Deux états étirés ou contractés, déclenchés par simple variation de pH, permettent le contrôle de l'orientation et de la distance entre les deux « stoppeurs » glucidiques non reliés de manière covalente. Des stations pyridiniums amides mono ou disubstitués inédites ont également été utilisées pour la synthèse de muscles moléculaires de plus large amplitude à effets co-conformationnels induits. Lors de la contraction du muscle par carbamoylation des ammoniums, la différence de localisation des macrocycles autour des stations pyridiniums amides, dépendante de la substitution des amides, engendre deux effets très différents : rôle de frein moléculaire de la DB24C8 ou basculement conformationnel impressionnant des chaises des mannopyranoses. Une étude méthodologique a été menée afin de classer les stations moléculaires rencontrées dans ce manuscrit, selon leurs affinités respectives pour la DB24C8, et a conduit à la conception d'un muscle moléculaire oscillant dont l'état varie continuellement entre contracté et semi-contracté en fonction de la température et de la nature du solvant. Enfin, différentes stratégies de synthèse ont été explorées pour obtenir des nœuds moléculaires inédits en forme de double lasso par cyclisation de synthons dimères de rotaxanes. Un double lasso dont la vitesse de rotation et la taille de la cavité peuvent être modulées en fonction du pH a ainsi été obtenu
This thesis is devoted to the synthesis of pH-sensitive molecular muscles and knots. The first molecular muscle has been readily synthesized and published in 2008, using a two-step strategy: 1) end-capping of the interlocked axles by copper(I)-catalyzed Huisgen alkyne-azide 1,3-dipolar cycloaddition, 2) methylation of triazoles to triazoliums, which are able to interact with the macrocycle DB24C8. Two stretched and contracted states, triggered by variation of pH, allow the control of the distance and of the orientation of the two glucidic ends, which are not covalently linked. Novel mono- and disubstituted pyridinium amide stations have been used for the synthesis of large-amplitude molecular muscles, whose translation of the macrocycles trigger a second co-conformational induced effect. In fact, upon contraction of the molecular muscle, using carbamoylation of the ammoniums, the slight different localizations of the macrocycles around the pyridinium amides (depending on their mono- or disubstitution) trigger two very different effects. The first one is a molecular break played by the DB24C8, whereas the second one is a flipping of the chair-like conformation of the mannopyranosyl ends. A methodologic study was then carried out with the aim to determine the relative affinity of the new described molecular stations for the DB24C8, and led to the synthesis of a molecular muscle which oscillates from the contracted to the semi-contracted co-conformation, depending on solvent and temperature. Eventually, different routes to very new double-lasso molecular knots were investigated from a molecular muscle building-block. One molecular knotted machine has been obtained, and has a double-lasso structure, whose rotation and size of its cavity can both been modulated by variation of pH

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35

Estarellas, Martín Carolina. "Theoretical and Experimental Study of Cooperativity Effects in Noncovalent Interactions." Doctoral thesis, Universitat de les Illes Balears, 2012. http://hdl.handle.net/10803/97288.

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L’any 2002 tres grups de recerca, entre ells el nostre grup, van demostrar teòricament que la interacció entre anions i anells aromàtics electrodeficients, anomenada interacció anió–, era favorable. Des de llavors s’ha dut a terme un intens estudi de la seva naturalesa física fins la total comprensió. Aquesta tesi es basa amb l’estudi de la interacció anió– des de tres punts de vista. Primerament, la investigació es basa en el disseny teòric de motius estructurals per donar lloc a un receptor on la interacció anió– siga molt favorable, per posteriorment avaluar la força de la interacció experimentalment en dissolució. A continuació, es va analitzar la interrelació entre un gran nombre de combinacions d’interaccions no covalents. A partir d’aquest estudi es defineixen nous conceptes i es proposen diferents formules per calcular efectes de cooperativitat. Finalment, hem anat un pas més enllà en l’estudi de la interacció analitzant: 1) l’impacte de la interacció anió– a sistemes biològics; 2) la influència de modificacions a l’anió sobre la naturalesa física de la interacció
In 2002 three research groups, among them our research group, theoretically demonstrated that the interaction between anions and electron-deficient aromatic rings, named anion– interaction, was favourable. Since then, an intense study of its physical nature has been performed to understand it completely. This thesis is based on the study of the anion– interaction from three points of view. Firstly, theoretical design of binding units to build a receptor and to obtain the most favourable binding based on anion– interactions. The binding properties of these receptors have been experimentally assessed in solution. Secondly, we have studied the interplay between a great combination of noncovalent interactions. From this study, new concepts and formula to calculate cooperativity effects have been described. Finally, we have study one step further the anion– interaction analysing: 1) the impact of anion– interaction in biological systems; 2) how the modifications in the anion influence the physical nature of the interaction.

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36

Perraud, Olivier. "Les hémicryptophanes : de la reconnaissance moléculaire à la catalyse supramoléculaire." Thesis, Lyon, École normale supérieure, 2012. http://www.theses.fr/2012ENSL0722.

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La synthèse de molécules possédant une cavité présente un grand intérêt car ces dernières peuvent agir comme récepteurs moléculaires ou comme catalyseurs supramoléculaires et ainsi mimer l'activité des enzymes. Les hémicryptophanes possèdent ainsi des cavités dissymétriques complexes formées à partir d'une unité cyclotrivératrylène et d'une seconde unité de symétrie C3 et présentent des propriétés catalytiques et de reconnaissance particulièrement intéressantes.Les travaux effectués au cours de cette thèse reposent donc sur la synthèse de nouveaux hémicryptophanes et sur leur utilisation pour la reconnaissance moléculaire de composés biologiquement actifs et pour la catalyse supramoléculaire. A ce titre, différentes voies de synthèse ont été abordées et ont permis d'obtenir un panel de nouveaux récepteurs. Ces composés ont alors été appliqués dans un premier temps à la reconnaissance sélective de paires d'ions et de neurotransmetteurs zwitterioniques puis à la reconnaissance stéréosélective de sucres. Les propriétés complexantes de ces composés ont principalement été étudiées par spectroscopie RMN et à l'aide de calculs quantiques. Enfin, la synthèse de complexes supramoléculaires cuivre-hémicryptophane nous a permis de développer l'utilisation de ces composés pour la catalyse biomimétique d'oxydation des alcanes
Molecular containers are very attractive as they can act as molecular receptors or supramolecular catalysts and so mimic biological entities such as enzymes. Hemicryptophanes are heteroditopic host molecules created from the association of a cyclotriveratrylene unit with another C3-symmetric moiety and which present interesting catalytic and recognition properties. During this thesis, we based our work on the synthesis of new hemicryptophanes and their application, first in molecular recognition of bioactive molecules and then in supramolecular catalysis. Different synthetic paths have been developed to obtain several new receptors. Their binding abilities have then been studied in selective recognition of ion pairs and neurotransmitters and in stereoselective recognition of carbohydrates. These works have been performed mainly thanks to NMR spectroscopy and quantum calculations. Finally, copper-hemicryptophane complexes have been synthesized and used as supramolecular catalysts in C-H oxidation of alkanes

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Long, Augustin. "Hémicryptophanes polytopiques énantiopurs : reconnaissance de molécules d'intérêt biologique et influence de la chiralité inhérente sur leurs structures." Electronic Thesis or Diss., Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0265.

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Les hémicryptophanes sont des molécules cages chirales combinant une unité CTV (cyclotrivératrylène) et une autre unité de symétrie C₃. Ces molécules ont trouvé de nombreuses applications allant de la reconnaissance moléculaire à la catalyse supramoléculaire, en passant par les machines moléculaires. En reconnaissance, ils sont capables de complexer efficacement et sélectivement certaines molécules d‘intérêt biologique comme les sucres ou les neurotransmetteurs. Leur activité catalytique remarquable est liée à la possibilité de fonctionnaliser de façon endohédrale l’intérieur de leur cavité pour permettre une augmentation de la stabilité du catalyseur, de sa sélectivité ou de son activité. De plus, la chiralité inhérente de ces récepteurs est utilisée pour la reconnaissance stéréosélective de substrats chiraux. Les travaux effectués dans cette thèse portent sur la synthèse, la fonctionnalisation et le dédoublement de nouveaux hémicryptophanes énantiopurs utilisés pour la reconnaissance de composés d’intérêt biologique. L’étude de la chiralité de ces récepteurs y est menée à la suite des dédoublements par HPLC chirale. Ces composés ont été appliqués à la complexation stéréosélective de sucres, puis leur fonctionnalisation a été réalisée pour obtenir des récepteurs fluorescents qui montrent de bonnes sélectivités pour la détection de neurotransmetteurs. L’influence de la chiralité du CTV sur la structure des hémicryptophanes a ensuite été étudiée. Enfin, de nouveaux CTV dissymétriques énantiopurs, obtenus par modification spatiale de l’arrangement des bras, ont été synthétisés pour de nouvelles applications en reconnaissance stéréosélective et catalyse asymétrique
Hemicryptophanes are chiral cage molecules combining both a CTV unit (cyclotriveratrylene) and another C₃ symmetrical unit. They were found to be efficient as receptor, in supramolecular catalysis, and can also act as molecular machines. Indeed, they display interesting recognition properties, and depending on the shape and size of their cavity, they can efficiently and selectively complex molecules of biological interest, such as carbohydrates or neurotransmitters. Their remarkable catalytic activities are related to the ability to obtain endohedral functionalization of their cavity. An increase of the catalyst stability, selectivity or activity has been observed after encapsulation of a catalytic site. Moreover, the inherent chirality of these receptors is used for stereoselective recognition of chiral substrates. The work of this thesis focuses on the synthesis, functionalization and resolution of new enantiopure hemicryptophanes for recognition of compounds of biological interest. The chirality of these receptors has been analyzed after their resolution by chiral HPLC. These compounds have been applied to the stereoselective complexation of carbohydrates and their functionalization was performed to obtain fluorescent receptors which show good selectivities for the detection of neurotransmitters. Then, the chirality-structure relationship has been studied. Finally, new enantiopure dissymmetric CTV, obtained by the modification of the spatial arrangement of the substituents, have been synthetized for new applications in stereoselective recognition and asymmetric catalysis

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Ibáñez, Jiménez Anna. "Sistemes basats en sals d’imidazoli: Plataforma pel desenvolupament de compostos d’interès químic i farmacèutic." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/108183.

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La Tesi Doctoral s’emmarca dins del projecte de recerca adreçat al estudi de la química de sistemes moleculars basats en sals d’imidazoli, que ve desenvolupant el nostre grup en els darrers anys. En concret la present Tesi Doctoral s’ha proposat una alternativa als mètodes clàssics, poc estudiada fins ara en líquids iònics, pel procés de bescanvi d’anió. La metodologia desenvolupada és senzilla d’aplicar i eficient donat que millora els rendiments descrits en la literatura, a vegades de forma substancial, proporcionant parells iònics lliures d’halur. El mètode basat en l’ús de reïnes de bescanvi iònic, permet obtenir sals de cations orgànics amb l’anió objectiu seguint un procés on es poden diferenciar dues parts. La primera correspon a la carrega de la reïna amb l’anió seleccionat [AER (forma A¯)], on s’han estudiat diferents vies com a font de l’anió i diversos solvents de càrrega segons el seu caràcter més o menys hidròfil. La segona correspon al bescanvi de l’anió halur examinant diferents solvents i mescles segons les característiques dels productes. A la senzillesa del protocol, s’hi afegeix el fet de que es minimitza la formació de productes secundaris tòxics, i la reïna utilitzada pel bescanvi és reciclable, amb el conseqüent benefici medi ambiental, entrant dins l’àrea de la química sostenible. El mètode ha estat aplicat amb èxit al bescanvi del contraanió en sals d’imidazoli, benzimidazoli, piridini i triazoli, així com en sals d’amoni quaternàries, amb propietats com a líquids iònics. La selecció de l’anió permet modular les seves propietats fisico-químiques, obtenir ILs per tasques especifiques, i disminuir la seva ecotoxicitat, entre altres possibilitats. La metodologia s’ha estès amb resultats excel•lents a sensors i receptors d’anions basats en sals d’imidazoli, monocatiònics i dicatiònics de forma que es facilita l’accés a compostos que podran ser útils per a l’estudi de propietats en l’àrea del reconeixement molecular d’anions, el que obre noves perspectives per a l’estudi d’aquests sistemes. Per altre part poden preparar-se sals d’ingredients farmacèutics actius (APIs), estratègia que pot permetre la modulació de les seves propietats proporcionant millores que incloguin el control de la solubilitat, la biodisponibilitat o bioactivitat, l’estabilitat, l'eliminació de polimorfisme, noves formes d’alliberament, o fins i tot permetre l’administració de còctels de fàrmacs personalitzats. Així, el mètode s’ha aplicat en la preparació de sals àcids arilpropiònics amb propietats antiinflamatòries en forma de líquids iònics, accedint als corresponents arilpropionats d’1-butil-3-metilimidazoli amb els que s’ha iniciat l’estudi del perfil d’alliberament del fàrmac. En la darrera part de la tesi, i dins de l’àrea del reconeixement molecular s’ha estudiat el comportament com a receptor abiòtic d’anions de [14]heterofans mitjançant estudis de complexació de RMN de 1H, observant que en CD3CN presenta afinitat pels anions clorur i acetat segons un model d’estequiometria 1:1 amb un valor de Ka (constant d’associació) proper al 104 mol–1 per l’anió acetat. A més a més, els resultats obtinguts en DMSO d6 indiquen una considerable afinitat pel anió H2PO4¯ si bé l’estudi resta pendent de completar
The PhD thesis is part of a research project aimed at studying the chemistry of imidazolium molecular systems, which our group has been developing in recent years. Initially, the current work was focused on the development of a simple and efficient protocol to obtain a halide exchange with a broad range of organic and inorganic anions in imidazolium ionic liquids (ILs) using an anion exchange resin (AER) as an alternative to the classical methods. This approach involves two steps: a) loading the anion in the AER, with different anions of variable hydrophilic character exploring sources and solvents and b) performing the halide exchange with the most suitable solvent mixture to obtain the new halide-free ion pair. Besides the advantage of this simplicity, this protocol minimized the formation of toxic byproducts, essential for sustainable chemistry, as well as featuring a recyclable AER. The AER (A¯ form) method has been applied to swap halides for assorted anions in several quaternary heteroaromatic salts that include imidazolium, benzimidazolium, pyridinium and triazolium salts, and quaternary ammonium salts, providing the halide-free ion pairs in excellent to quantitative yields. The methodology has been extended with excellent results to anion receptors and sensors based on monocationic and dicationic imidazolium salts. Thus, access has been facilitated to potentially useful compounds in the area of anion molecular recognition, which opens new perspectives for the study of these systems. Additionally, the developed protocol was successfully extended to prepare salts from active pharmaceutical ingredients (APIs), modifying their properties. An imidazolium cation was combined with the anion of an anti-inflamatory arylpropionic acid to obtain the ionic liquid salt. A study of the release of API from hyaluronan-based hydrogels as drug delivery system is currently underway. In the final part of the thesis, specifically in the area of molecular recognition, we have explored the behaviour of [14]heterophanes as abiotic receptors using 1H-NMR techniques to study their anion binding properties. As an example, in CD3CN, the acetate anion showed a Ka value of nearly 104 mol–1. The results obtained open perspectives for further work in this field.

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Mokhtar, Mohd Noriznan. "Biocatalytic Production, Preparation and Characterization of Large-ring Cyclodextrins." Doctoral thesis, Universitätsbibliothek Chemnitz, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200900431.

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Cyclodextrins (CD) are cyclic oligosaccharides composed of six to more than sixty glucose units. Large-ring cyclodextrins (LR-CD) are novel CD comprised of more than eight glucose units with cavity structures and sizes different from that of commercially available CD₆ – CD₈. LR-CD may offer unique molecular recognition properties and can be produced biocatalytically from starch using cyclodextrin glucanotransferase (CGTase, E.C. 2.4.1.19) in a short reaction time. LR-CD were isolated from glucose, CD₆ – CD₈ and other compounds by complexation of CD₆ – CD₈ as well as precipitation techniques. The yield of LR-CD (degree of polymerization from 9 to 21) was optimized using central composite design. Addition of polar organic solvents to the synthesis resulted in higher yields of LR-CD. LR-CD composed of 9 to 21 glucose units were successfully separated using reversed-phase of ODS-AQ chromatography and normal-phase of polyamine II chromatography. Maintaining optimized reaction conditions aided in a high yield of CD₉; it could be separated with reasonable yield using a single step of polyamine II chromatography. A co-grinding method helped to obtain higher solubilization levels of glibenclamide, vitamin A acetate and vitamin D₃ in CD₁₃, CD₁₀ and CD₁₁, respectively when compared to other CD. Vitamin K₁ was solubilized in distilled water with CD₆ – CD₁₃ using a co-precipitation method. When compared with other CD, CD₉ was seen to be the best solubilizer. The analysis of complexes using ESI MS showed spironolactone and glibenclamide complexed with CD₉ and CD₁₃, respectively.

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Santos, Figueroa Luis Enrique. "New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest." Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/43216.

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El presente proyecto de investigación está enfocado al desarrollo de sensores químicos fluoro-cromogénicos, para la detección y determinación de especies químicas de interés biológico, industrial y medioambiental de forma selectiva y con alta sensibilidad. En forma general, se busca el diseñar nuevos sistemas sensores basados en compuestos (receptores) formados por dos unidades: una unidad coordinante que interacciona con el anión a determinar y una unidad generadora de señal que alerta del reconocimiento molecular efectuado. Durante este estudio se están preparando diversas moléculas receptoras funcionalizandas con grupos modificadores de estructura para evaluar su influencia sobre las capacidades de detección y selectividad como receptores de especies específicas en diferentes condiciones y medios. Las diferentes aproximaciones en prueba implican a su vez el diseño y síntesis molecular, así como el análisis de las diferentes señales ópticas producidas en el reconocimiento, con el fin de diseñar sistemas de alta eficacia y eficiencia, y con posibilidades reales de aplicación.
Santos Figueroa, LE. (2014). New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/43216
TESIS
Premiado

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Larpent, Patrick. "Tectonique moléculaire : conception et formation de polymères de coordination chiraux." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAF044/document.

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La formation de polymères de coordination poreux et chiraux ainsi que leur utilisation pour des processus énantiosélectifs est actuellement un des domaines de grand intérêt en chimie. La formation de ces matériaux est rendue possible par le biais des concepts développés dans le domaine de la tectonique moléculaire. Les travaux présentés dans cette thèse s’inscriventdirectement dans cette thématique. Les synthèses de tectons organiques chiraux sont présentées. Leur combinaison avec divers centres métalliques, via différentes méthodes de cristallisation, a permis l’obtention de monocristaux qui ont été étudiés par diffraction des rayons X sur monocristal. Dans un premier temps, des polymères de coordination homochiraux, obtenus par l’utilisation de tectons dotés de sites coordinants neutres sont présentés. Des réseaux de type cuboïde présentant des canaux monodimensionnels au sein de leur architecture sont notamment décrits. Par la suite, des édifices mono- et bi-dimensionnels de géométries diverses sont discutés. Pour certains de ces cristaux, des interactions de plus faible énergie que la liaison de coordination permettent la formation de réseaux moléculaires de plus haute dimensionnalité. Enfin, dans une dernière partie, l’utilisation de tectons dotés de sites coordinants chargés est discutée. Des réseaux tridimensionnels homochiraux poreux et robustes sont décrits. Ces derniers sont des candidats de choix pour des procédés énantiosélectifs de séparation. Leur propension à encapsuler des gaz (N2 et CO2) est présentée
The synthesis and the use of porous chiral coordination polymers for enantioselective processes are of current interest and prime importance in chemistry. These crystalline materials are mainly obtained by combinations of well-designed organic tectons and properly chosen metallic components. This thesis deals with the synthesis of organic chiral building blocks and their combinations with a variety of metallic salts leading to chiral coordination networks. In a first part, the use of tectons bearing neutral coordinating sites is described. Homochiral cuboid architectures displaying monodimensional channels are presented. In the second part, mono- and bi-dimensional networks of various geometries are described. In some cases, within crystals, interactions lower in energy than the coordination bond are observed and are responsible for the formation of molecular networks of higher dimensionality. Finally, the use of organic tectons displaying charged interaction sites is presented. Their combination with metallatectons under thermal treatments affords robust tridimensional homochiralarchitectures displaying cavities. These materials are interesting candidates for enantioselective recognition and separation. Their gas adsorption propensity (N2 and CO2) is briefly discussed

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Schmitt, Aline. "Reconnaissance de molécules d'intérêt biologique par les hémicryptophanes - stéréosélectivité, reconnaissance dans l'eau et fluorescence." Thesis, Lyon, École normale supérieure, 2014. http://www.theses.fr/2014ENSL0916.

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La reconnaissance moléculaire est un phénomène omniprésent dans les systèmes vivants et intervient dans de nombreux processus biologiques comme la reconnaissance cellulaire ou encore la transmission de signaux par les neurotransmetteurs. L’élaboration de molécules synthétiques capables de mimer l’action des récepteurs naturels en complexant sélectivement un substrat cible est, à l’heure actuelle, très recherchée pour la détection ou le diagnostic en biologie et médecine. Parmi l’ensemble des récepteurs synthétiques, les hémicryptophanes sont des molécules cages composées d’un cyclotribenzylène connecté à une autre unité moléculaire par trois bras espaceurs. Les travaux de cette thèse reposent sur l’élaboration de nouveaux hémicryptophanes et l’étude de leurs propriétés de complexation vis-à-vis de molécules d’intérêt biologique. Dans un premier temps, la chiralité de ces récepteurs a été utilisée pour étudier leurs propriétés de reconnaissance stéréosélective face à différents sucres et analogues de neurotransmetteurs. De bonnes diastéréosélectivités et énantiosélectivités ont ainsi pu être observées en milieu organique pour les substrats étudiés. En parallèle, plusieurs hémicryptophanes hydrosolubles ont été synthétisés et ont permis de reconnaitre sélectivement des neurotransmetteurs comme la choline dans l’eau. Enfin, une dernière partie de cette thèse à été consacrée à la mise en place d’une voie de synthèse pour rendre ces récepteurs fluorescents, dans le but d’élaborer par la suite des sondes moléculaires capables de détecter et de suivre spatio-temporellement des molécules d’intérêt biologique dans les systèmes vivants par fluorescence
Molecular recognition is a very important phenomenon for living systems as it occurs in many biological processes like cell-cell recognition or transmission of signals by neurotransmitters. Nowadays, the design of synthetic host molecules able to mimic natural receptors by complexing selectively a target substrate, is much sought-after for detection or diagnostic in biology and medicine. Among all the different synthetic receptors, hemicryptophanes are cage-shape molecules which are composed of a cyclotribenzylene moiety connected to another molecular unit by three spacer arms. This thesis is about the synthesis of new hemicryptophanes and the study of their complexation properties toward biologically important molecules. First, the stereoselective recognition of carbohydrates and neurotransmitter analogues by these chiral receptors was investigated in organic solvents and revealed good enantioselectivities and diastereoselectivities. In parallel, several water-soluble hemicryptophanes were synthesized and showed an aptitude for recognizing selectively ammonium substrates like choline in water. The last part was devoted to the development of a synthetic pathway to make hemicryptophanes fluorescent, in order to design molecular probes able to track biologically important molecules in living systems by fluorescence

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Mirabaud, Anaïs. "Développement d'une chimie hôte-invité pour la valorisation du CO2 via une catalyse éco-compatible." Thesis, Lyon, École normale supérieure, 2015. http://www.theses.fr/2015ENSL1052/document.

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Le développement de procédés catalytiques pour la valorisation chimique du dioxyde de carbone (CO2), suscite un intérêt grandissant en termes de chimie du carbone et de développement durable. Les travaux de cette thèse portent sur l’étude de la synthèse de carbonates cycliques à partir du couplage du CO2 avec des époxydes. De nombreux catalyseurs ont été développés dont les sels d’ammoniums fournissant le nucléophile nécessaire pour initier la réaction par ouverture de l’époxyde. Notre projet propose une nouvelle approche qui consiste à augmenter la nucléophilicité du catalyseur via une chimie hôte-invité dans laquelle des récepteurs moléculaires de type cavitands viennent sélectivement encapsuler les cations ammoniums, libérant ainsi l’anion nucléophile pour une meilleure réactivité. Notre système catalytique, testé à 1 bar de CO2, a notamment démontré tout son potentiel par l’activation accrue de sels de tétraméthylammonium initialement inactifs. Des expériences effectuées sous une pression de CO2 de 10 bar, ont permis d'étudier l’influence de la structure des cavitands et de montrer qu’une double activation était possible grâce à la conception de cavitands comportant des fonctions acides de Brönsted et des propriétés d’encapsulation optimales. Une application à la catalyse hétérogène a finalement été initiée par l’immobilisation des ammoniums ou des cavitands sur des supports à base de silice pour profiter des avantages de tels procédés
The utilization of carbon dioxide (CO2) as a key component in organic transformations has recently drawn much attention as a greener alternative to fossil fuel based resources. The objectives of this work aim at studying the synthesis of cyclic carbonates from the coupling of CO2 with epoxide. Numerous catalysts have been proposed for this reaction among which the ammonium halides providing the nucleophile to initiate the reaction by opening the epoxide. Herein, we propose a new approach based on host-guest chemistry, to improve catalytic reactivity by increasing the nucleophilicity of the halide anion. For this purpose, cavitand molecular receptors able to bind quaternary ammonium ions are used, releasing the anionic nucleophile for the initial epoxide ring-opening reaction. At CO2 atmospheric pressure, our catalytic systems demonstrated a great potential by the dramatic activation of tetramethylammonium halides, whereas when used alone, these catalysts had never shown any activity. The influence of the cavitand structure was investigated through experiments run under 10 bar of CO2 pressure, and revealed that a double activation was possible with cavitand bearing Brönsted acidic hydroxyl functions and optimal recognition properties. The heterogeneization of such catalytic systems was finally studied with the grafting of either ammoniums or cavitands on silica based materials

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Lefèvre, Sara. "Synthèse de récepteurs cyclotribenzylènes et hémicryptophanes : propriétés chiroptiques, reconnaissance moléculaire et fluorescence." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEN016.

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Une grande partie des chimistes puisent leur inspiration auprès de la biologie. C’est le cas des chercheurs en chimie supramoléculaire, qui travaillent sur l’élaboration de récepteurs moléculaires synthétiques capables d’effectuer des reconnaissances moléculaires envers des substrats d’intérêt biologiques. Le but est ainsi de mimer l’activité des protéines naturelles, en vue d’applications cliniques.L’unité cyclotribenzylène (CTB) est une structure de symétrie C3 qui possède des propriétés complexantes intéressantes. Un CTB relié à une deuxième unité complexante par trois bras espaceurs constitue la famille des hémicryptophanes. Au cours de cette thèse, nous avons travaillé sur l’élaboration de récepteurs moléculaires basés sur cette unité CTB. Dans un premier temps nous avons développé une nouvelle méthode de synthèse d’hémicryptophane énantiopurs à l’échelle du gramme en vue d’effectuer des reconnaissances stéréosélectives de neurotransmetteurs chiraux. Nous avons ensuite développé des récepteurs CTB et hémicryptophanes combinant la chiralité du CTB et du groupement binaphtol. La configuration absolue des unités chirales ont été déterminées par une méthode de corrélation chimique. Ces récepteurs ont été utilisés pour réaliser des expériences de reconnaissance stéréosélective de saccharide et de bonnes diastéréosélectivités ont été obtenues. Enfin, nous avons travaillé sur l’élaboration d’une voie de synthèse d’hémicryptophanes fluorescents capables de subir des excitations bi-photoniques dans le but d’effectuer des expériences de suivi dans l’espace et dans le temps de substrats d’intérêt biologiques en milieu in-vivo
Biology is an inspiration for chemists. Especially for the field of supramolecular chemistry, which one of the aim is to develop synthetic molecular receptors capable of molecular recognition to biological substrates, to mimic the activity of natural proteins for clinical applications.Cyclotribenzylene unit (CTB) is a C3-symmetry structure which present interesting recognition properties. When a CTB is connecting to another molecular unit by three spacers arms, it forms an hemicryptophane receptor. During this thesis, we worked on elaboration receptors based on CTB unit. First, a new way of enantiopure hemicryptophane synthesis on gram scale has been developed for stereoselective recognition of chiral neurotransmitters. Then receptors based on chirality of CTB and binaphthol unit has been developed. Assignment of absolute configuration of chiral unit was determined by a chemical correlation. Stereoselective recognition of carbohydrates by these receptors revealed good diastereoselectivity. Finally, a synthetic pathway leading to fluorescent hemicryptophanes was developed for bi-photonic excitation in order to realize in-vivo experiments of tracking biological substrates

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Lock, Julia. "Cyclodextrins : molecular wheels for supramolecular chemistry /." Title page, table of contents and abstract only, 2004. http://web4.library.adelaide.edu.au/theses/09PH/09phl8131.pdf.

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Thesis (Ph.D.)--University of Adelaide, School of Chemistry and Physics, Discipline of Chemistry, 2005?
"July 2004" Includes copies of publications by the author as appendix. Includes bibliographical references.

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Edwards, William. "Molecular recognition and component selection in supramolecular gels." Thesis, University of York, 2013. http://etheses.whiterose.ac.uk/4664/.

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This thesis will cover aspects of molecular recognition and component selection in supramolecular gels. In the first section a bola-shape alkene appended organogelator is tested for its response to a number of cations. The gelator was found to undergo a gel-sol transition upon addition of Li+ and Ag+ and not when either Na+ or K+ was added. The response to Li+ was caused by the higher charge density of the ion compared to the other group I metals, allowing it to disrupt the intermolecular hydrogen bonding between the gelator molecules. The response to Ag+ was shown to be due to an interaction between this ion and the alkene groups of the gelator. This demonstrated that the silver(I)-alkene interaction can be utilised in the gel phase. The second part of this thesis will investigate the formation of multi-component gels based on 1:1 complexes formed between a lysine based, carboxylic acid bearing dendron and a monoamine. The forces underpinning gelation as well as the effect of changing the solvent and changing the amine used are all investigated. This section then explores component selection, where a number of possible amines are added to a starting mixture but the dendron will form a gel with predominately one of the amines in preference to the others. The amines that are not incorporated into the network were easily viewed by NMR spectroscopy. A number of different amines were tested which all formed gels of different thermal stabilities with the dendron and also had different pKa values. Both of these factors were shown to be important in driving the preferential selection of a certain amine as they described the amines ability to form a complex with the dendron (pKa) and assemble as part of a gel network (thermal stability). The thesis then describes the effect of using chiral amines, enantiomers of which form complexes with the chiral dendron which are diastereomeric. The effect of using different enantiomers of an amine was studied and found to dramatically alter the structure of the gelator network and the behaviour of the gel formed. These effects could be tuned by mixing different amounts of each enantiomer into the sample. As the gels formed with different enantiomers had different thermal stabilities they were able to be used in a number of experiments to test for component selection. These did indeed show this effect to be taking place, with the enantiomer which formed the most stable gel preferentially incorporated into the gelator network. The final section of this thesis reverses the concept in the previous section and investigates the effect of changing the chirality of the lysine based dendron when mixing it with non-chiral amines, or a single enantiomer of a chiral amine. When mixed with non-chiral amines, as expected, changing the chirality of the dendron changed the structure of the gelator network and the properties of the gel formed and this could be tuned by mixing different amounts of the dendron enantiomers. Unexpectedly, this resulted in more thermally stable gels being formed with the racemic mixtures rather than their enantiopure equivalents, a very rare occurrence. When chiral amines were used the results were very similar to the previous section, with different enantiomers of the dendron changing the nano-scale structure of the network and the properties of the gels formed. Again this effect could be tuned by using different amounts of the dendron enantiomers to form the gel. Finally these systems were also tested to see if they could exhibit component selection but this study was inconclusive, partly down to the disruptive effect excess dendron had on the gel network formed.

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Huxley, Allen John McAllister. "Switches based on molecular recognition processes." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322948.

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Corso, Romain. "Conception et étude des propriétés physico-chimiques de réseaux de coordination." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF019/document.

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L’essor de la chimie supramoléculaire et plus particulièrement de la tectonique moléculaire a rendu la formation de matériaux poreux hautement organisés possible. La fonctionnalisation de tels composés favorise leur utilisation pour de nombreuses applications. Les travaux présentés dans cette thèse ont été consacrés aux réseaux moléculaires poreux homochiraux ainsi que leur utilisation pour le stockage de gaz, la reconnaissance et la séparation d’énantiomères.Le premier chapitre décrit la synthèse de divers ligands organiques optiquement purs et leur assemblage avec des sels de cuivre pour l’obtention de monocristaux. Les isothermes d’adsorption de chacun de ces composés cristallins ont été mesurés via des analyses BET et le stockage de N2,CO2 et CH4 ont été évalué.Le second chapitre s’intéresse à l’utilisation de ces mêmes composés chiraux pour la reconnaissance des énantiomères (L)- et (D)-tryptophane. Des tests de séparation énantiosélective de molécules aminées ou dérivées d’amides sont également exposés.Le dernier chapitre décrit la formation de réseaux moléculaire mono- et tridimensionnels par l’association de ligands organiques avec des sels métalliques variés. Leurs structures cristallines ont pu être déterminées par diffraction des rayons X sur monocristal
The development in supramolecular chemistry and more particularly in molecular tectonics has madepossible the formation of porous and highly organized materials. The functionalization of suchcompounds favored their use for various applications. This PhD work is about the application ofporous homochiral coordination networks for storage, enantioselective recognition or separation.The first chapter deals with the synthesis of chiral ligands and their combinations with copper salts toenable the formation of single crystals. Their adsorption isotherms were evaluated by BETmeasurements. Storage of N2, CO2 and CH4 by these crystalline architectures was also evaluated.The second part describes the use of these chiral compounds for enantioselective recognition of (L)-and (D)-tryptophan. Tests of enantioselective separation of amines or amides were also carried out.The last part of this work deals with the formation of mono- or tridimensional coordination polymersby combinations of organic ligands and a variety of metallic salts. Their structures were determinedby X-ray diffraction on single crystal

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Chatelet, Bastien. "Aspects non usuels de la chimie des azaphosphatranes et proazaphosphatranes : application en organocatalyse." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2013. http://tel.archives-ouvertes.fr/tel-01070639.

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Abstract:

Les proazaphosphatranes sont des entités phosphorées bicycliques superbasiques également connues sous le nom de superbases de Verkade et les azaphosphatranes constituent leurs acides conjugués. Les travaux de cette thèse porte sur l'étude des propriétés de ces molécules en milieu confiné. Premièrement, le confinement des superbases a été étudié au sein de structure de type hémicryptophane (molécules possédant des cavités dissymétriques formées à partir d'une unité cyclotrivératrylène et d'une seconde unité de symétrie C3). Une modulation de la basicité a pu être notamment observée dans les différentes structures étudiées possédant des tailles de cavité différentes par comparaison avec les superbases modèles dépourvues de cavité. L'activité catalytique d'une superbase encagée a pu être testée dans deux réactions de catalyse nucléophile et basique. Puis les azaphosphatranes, acides faibles aux stuctures robustes, jusque-là peu utilisés en organocatalyse ont été valorisés pour la synthèse de carbonates cycliques à partir d'époxydes et de dioxyde de carbone (CO2). Un effet sur la stabilité des catalyseurs encagés a pu être démontré. Enfin un catalyseur hétérogène a pu être mis au point par immobilisation d'un azaphosphatrane sur silice mésoporeuse de type SBA-15.

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Eryazici, Ibrahim. "SUPRAMOLECULAR CHEMISTRY OF FUNCTIONALIZED TERPYRIDINES." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1195677178.

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Dissertations / Theses on the topic 'Supramolecular chemistry; Molecular recognition'

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