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1
Brown, Alec Nathaniel. "Late-Stage Functionalization of 1,2-Dihydro-1,2-Azaborines". Thesis, Boston College, 2015. http://hdl.handle.net/2345/bc-ir:104564.
Testo completoAbstract (sommario):
Thesis advisor: Shih-Yuan LiuDescribed herein are two distinct research projects focused on the development of metal-catalyzed late-stage functionalization strategies for 1,2-dihydro-1,2-azaborines separated into three chapters. The first chapter discusses the development, synthesis, and recent contributions to the field of azaborine chemistry. The second chapter details the development of rhodium catalyzed B-H bond activation for the synthesis of a new class of BN-stilbenes as well as the discovery of a novel B-H to B-Cl transformation that is successful both with B-H azaborines as well as other B-H containing compounds. The third chapter pertains to the development of a B-H and B-Cl tolerant C(3) functionalization strategy through the use of Negishi cross-coupling. Using this methodology, previously unreported isomers of BN-naphthalene and BN-indenyl have been synthesized and characterized
Thesis (PhD) — Boston College, 2015
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
2
Canelli, Tommaso. "Development of tandem C-H borylation/functionalization procedures for late stage functionalization of compounds". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9273/.
Testo completoAbstract (sommario):
The development of procedures for the iridium catalyzed C-H borylation of 1-aryl pyrazolopyrimidines and 1-aryl indazoles is reported. Investigation on the activity of the catalyst revealed the combination of an iridium (I) precursor and tetramethylphenantroline as the best catalytic system. Moreover, the procedures are regioselective resulting in the selective borylation of different C-H bonds within the substrates. The application of C-H borylation to late stage functionalization is demonstrated: a biologically active compound in AstraZeneca's project underwent tandem borylation/oxidation reaction, in order to obtain a functionalized product containing an OH group.
3
Bentley, Sierra Kathleen. "Selective Direct Borylation and Late-Stage Functionalization of 1,2-Azaborines:". Thesis, Boston College, 2020. http://hdl.handle.net/2345/bc-ir:109014.
Testo completoAbstract (sommario):
Thesis advisor: Shih-Yuan LiuDescribed herein is the development of a method to directly borylate the C5-position of monocyclic 1,2-azaborines without the use of a metal catalyst, kinetic resolution or directing group. This method tolerates different substitution on the boron as well as at the C3-position of the azaborine. A new BN-isostere of the drug molecule, felbinac, was synthesized to demonstrate the application of this method
Thesis (MS) — Boston College, 2020
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
4
Kaplaneris, Nikolaos [Verfasser]. "Resource-Economical C–H Activation for Late-Stage Functionalization / Nikolaos Kaplaneris". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2021. http://d-nb.info/1237128854/34.
Testo completo
5
Armand, Jeremy Richard. "Late Stage Functionalization of 1,2-Azaborines for Application in Biomedical Research:". Thesis, Boston College, 2019. http://hdl.handle.net/2345/bc-ir:108646.
Testo completoAbstract (sommario):
Thesis advisor: Shih-Yuan . LiuChapter 1. Use of boron as a pharmacophore is as growing but still underdeveloped strategy for expanding chemical space in biomedical research. In addition to more established methods of incorporating boron in drug development, an attractive and emerging method of introducing boron into biologically active compounds is through boron-nitrogen containing heterocycles. In particular, the Liu group has focused on exploring the interactions of monocyclic 1,2-azaborines in biological space. In order to install complicated chemical functionality needed for further studies, methods for late stage functionalization of 1,2-azaborines must be developed. Described herein is a method for functionalizing 1,2-azaborine at the C3- and C5-positions, with bromine and iodine handles, respectively. Chapter 2. Described is the application of the turbo Grignard reaction to 1,2-azaborines bearing a B–Cl bond. The reaction utilizes iPrMgCl·LiCl to form aryl carbon nucleophiles and is tolerant of sensitive functional groups such as nitriles and esters. Development of the reaction obviates the need to use toxic organotin reagents to install aryl groups at the B-position that bear sensitive, electrophilic functionalities
Thesis (MS) — Boston College, 2019
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
6
Chan, Jessica Zee. "Stereoselective Functionalization of Carbonyl Compounds and N-Alkylamines Promoted by Cooperative Catalysts:". Thesis, Boston College, 2020. http://hdl.handle.net/2345/bc-ir:108940.
Testo completoAbstract (sommario):
Thesis advisor: Masayuki WasaThis dissertation describes the development of cooperative catalyst systems for the functionalization of monocarbonyl compounds and stereoselective transformations of alpha-C–H bonds of N-alkylamines, inspired by the concepts of frustrated Lewis pairs (FLPs). Prior to this dissertation research, practical and broadly applicable C–C and C–heteroatom bond forming reactions involving the FLP complexes that provide synthetically desirable products with high enantioselectivity remained to be developed. Chapter 1 of this dissertation describes the recent advances in the transformations involving FLPs and B(C₆F₅)₃-catalyzed reactions. Inspired by the unique capability of FLP catalysts to activate otherwise unreactive molecules, and circumvent undesirable acid–base complexation, we have developed potent cooperative acid/base catalysts for C–C bond forming reactions of various monocarbonyl compounds and an appropriate electrophile, which will be discussed in Chapter 2. Another reactivity of FLPs to be explored has to do with the catalytic and enantioselective reactions of N-alkylamines, where two Lewis acid catalysts with potentially overlapping functions, work cooperatively to activate alpha-amino C–H bonds and promote the enantioselective C–C bond forming reaction between N-alkylamines and a nucleophilic species. In Chapter 3, B(C₆F₅)₃-catalyzed union of N-alkylamines and silicon enolates followed by the enantioselective B(C₆F₅)₃/Mg–PyBOX-catalyzed alpha-alkylation of N-alkylamines and alpha,beta-unsaturated compounds to form beta-amino carbonyl compounds will be described. In Chapter 4, B(C₆F₅)₃/Cu–PyBOX-catalyzed alpha-C–H alkynylation of N-alkylamines and the applications in late-stage functionalization and stereoselective synthesis will be discussed
Thesis (PhD) — Boston College, 2020
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
7
Schischko, Alexandra. "Late-Stage Peptide Functionalization by Ruthenium-Catalyzed C H Arylations and Alkylations". Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E4F4-0.
Testo completo
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Zhang, Zhuan. "Late Stage Modifications of Phosphines using Transition-Metal-Catalyzed C–H Bond Functionalization". Thesis, Rennes, Ecole nationale supérieure de chimie, 2020. http://www.theses.fr/2020ENCR0067.
Testo completoAbstract (sommario):
L'objectif principal de cette thèse de doctorat porte sur la préparation de phosphines polyfonctionnelles par diversification tardive de ligands commerciaux. Nous avons développé l'alkylation la liaison C–H en position ortho' des biarylphosphines catalysée par le rhodium(I). Cette nouvelle méthodologie permet d'accéder facilement à une vaste bibliothèque de phosphines multifonctionnelles. Certains de ces ligands modifiés ont surpassé les phosphines disponibles dans le commerce dans la carboxylation des bromures d'aryle catalysée par le palladium avec du dioxyde de carbone en présence d'un catalyseur photoredox. Pour améliorer la diversité des biarylphosphines, nous avons également perfectionné l'alcénylation des liaisons C–H dirigées par l’atome de posphore(III) des (dialkyl)- et (diaryl)biarylphosphines à partir d'alcynes internes. Le [Rh(OAc)(COD)]2 sans chlorure est un meilleur catalyseur que le [RhCl(COD)]2. Les conditions ont été développées pour contrôler la mono- et la difonctionnalisation. Une de ces nouvelles (dialkyl)biarylphosphines bisalcénylées a été utilisée pour la préparation d'un complexe de palladium(II), et certains de ces ligands fonctionnalisés ont surpassé leurs phosphines non fonctionnalisées correspondantes dans l'amidation palladocatalysée de chlorures d'aryle encombrés. Enfin, nous avons également exploré un nouveau protocole pour l'alkylation des liaison C-H de phsophines via la formation des intermédiaires phosphine-ruthénium cyclométallé à 5 ou à 7 chaînons. Ces phosphines fonctionnalisées ont le potentiel d'améliorer les réactions de couplage croisé des (pseudo)halogénures d'aryle encombrésThe main objective of this PhD thesis deals with the preparation of polyfunctional phosphines by late-stage diversification of commercially available ligands. We have developed rhodium(I)-catalyzed ortho’- C–H bond alkylation of biarylphosphines. This new methodology provides a straightforward access to a large library of multifunctionalized phosphines. Some of these modified ligands outperformed commercially available phosphines in the Pd-catalyzed carboxylation of aryl bromides with carbon dioxide in the presence of a photoredox catalyst. To improve the diversity of biarylphosphines, we have also perfected the P(III)-directed C−H bond alkenylation of (dialkyl)- and (diaryl)biarylphosphines using internal alkynes. Chloride-free [Rh(OAc)(COD)]2 acts as a better catalyst than [RhCl(COD)]2. Conditions were developed to control the mono- and difunctionalization. One of these novel bisalkenylated (dialkyl)biarylphosphines was employed for the preparation of a palladium(II) complex, and some of these functionalized ligands outperformed their corresponding unfunctionalized phosphines in Pd-catalyzed amidation of sterically hindered aryl chlorides. Finally, we have also explored a novel protocol C–H bond alkylation of phosphines via 5- or 7- membered ring cyclometallated phosphineruthenium intermediates. These functionalized phosphines have potential to improve crosscoupling reactions of sterically hindered aryl (pseudo)halides
9
Poudel, Dhruba P. "Late-Stage Modification of Polyurethane Dendrimers Using Click Chemistry". Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1627490978861964.
Testo completo
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Hanson, Susan Kloek. "Synthesis and reactivity studies of late transition metal complexes relevant to C-H bond activation and functionalization /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/8631.
Testo completo
11
Börgel, Jonas Verfasser], Tobias [Akademischer Betreuer] Ritter e Franziska [Akademischer Betreuer] [Schönebeck. "Late-stage functionalization of arenes: from C-H amination to C-H oxygenation and deoxyfluorination / Jonas Börgel ; Tobias Ritter, Franziska Schoenebeck". Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/121086293X/34.
Testo completo
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Sang, Ruocheng Verfasser], Tobias [Akademischer Betreuer] Ritter e Carsten [Akademischer Betreuer] [Bolm. "Late-stage functionalization of arenes: site-selective C-H oxygenation and fluorination via aryl sulfonium salts / Ruocheng Sang ; Tobias Ritter, Carsten Bolm". Aachen : Universitätsbibliothek der RWTH Aachen, 2020. http://d-nb.info/1221697455/34.
Testo completo
13
Böhm, Marvin Jeldrik. "Synthesis and reactivity of succinylthioimidazolium salts: A unified strategy for the preparation of thioethers". Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-152E-1.
Testo completo
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Zhu, Yingjun. "Sustainable Strategies for Site-Selective C–H Functionalizations of N-Heterocycles". Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://hdl.handle.net/11858/00-1735-0000-0022-5DDA-D.
Testo completo
15
Leroux, Marcel Rainer [Verfasser], e Paul [Akademischer Betreuer] Knochel. "Late-stage functionalization of peptides and cyclopeptides using organozinc reagents and pyrrole protected 2-Aminoalkylzinc reagents for the enantioselective synthesis of amino derivatives / Marcel Rainer Leroux ; Betreuer: Paul Knochel". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2020. http://d-nb.info/1208150057/34.
Testo completo
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Schischko, Alexandra [Verfasser], Lutz [Akademischer Betreuer] Ackermann, Lutz [Gutachter] Ackermann, Dietmar [Gutachter] Stalke, Manuel [Gutachter] Alcarazo, Franziska [Gutachter] Thomas, Shoubhik [Gutachter] Das e Alexander [Gutachter] Breder. "Late-Stage Peptide Functionalization by Ruthenium-Catalyzed C H Arylations and Alkylations / Alexandra Schischko ; Gutachter: Lutz Ackermann, Dietmar Stalke, Manuel Alcarazo, Franziska Thomas, Shoubhik Das, Alexander Breder ; Betreuer: Lutz Ackermann". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1170955819/34.
Testo completo
17
Mamontov, Alexander. "Hydroxylation et halogénation directe et sélective des composés azotés en milieu superacide". Thesis, Poitiers, 2018. http://www.theses.fr/2018POIT2267.
Testo completoAbstract (sommario):
La fonctionnalisation tardive de molécules (Late stage functionalization – LSF) offre l’opportunité d’explorer l’espace chimique plus efficacement, en particulier en considérant les liaisons C-H aromatiques comme des points potentiels de diversification pour générer de nouveaux analogues directement en une seule étape au lieu de faire une synthèse totale dite de novo. La fonctionnalisation directe de composés élaborés peut en particulier se faire en utilisant la technologie superacide comme démontré par les nombreux travaux du professeur Jacquesy. L’un des meilleurs exemples de cette stratégie est certainement la transformation directe de la vinorelbine (Navelbine®) par fluoration en conditions superacides pour conduire à son analogue difluoré (Vinflunine), commercialisé par les laboratoires Pierre Fabre comme agent anticancéreux Javlor®. C’est dans ce contexte que ce travail de thèse a porté sur le développement de nouvelles méthodes de fonctionnalisation directe de composés aromatiques azotés.Il s’agissait effectivement de développer de nouveaux outils de synthèse en conditions superacides afin :1. d’hydroxyler directement des composés aromatiques par voie électrophile;2. d’halogéner des composés aromatiques azotés allant d’anilines simples à des composés élaborés naturels ou de synthèse;3. d’appliquer ces méthodes à la synthèse de molécules marquées par des isotopes stablesLate-stage functionalization can now be considered as a synthetic tool of choice to create molecular diversity, especially in a medicinal chemistry context. For example, aromatic C-H bonds can be regarded as functional groups and points of potential diversification to generate new analogs of a lead structure without resorting to de novo synthesis.The direct functionalization of elaborated compounds can also be done using superacid chemistry as demonstrated by the previous work of professor Jacquesy. One of the best examples of this strategy is certainly the direct transformation of vinorelbine (Navelbine®) by fluorination in superacid conditions to lead to its difluorinated analogue (Vinflunine), marketed by Pierre Fabre laboratories as an anticancer agent Javlor®.In this context, these studies focused on the development of new methods for the direct functionalization of aromatic nitrogen containing compounds.In particular, this work aimed at developing new synthetic tools in superacid for:1. the direct hydroxylation of aromatic compounds;2. the halogenation of aromatic nitrogen compounds from simple anilines to naturally occurring or synthetic compounds;3. the synthesis of labelled compounds with stable isotopes
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Panza, Florian. "Fοnctiοnnalisatiοn directe οrthοgοnale métallο-catalysée des sites carbοne-hydrοgène des platefοrmes pharmacοlοgiques à cοeur imidazοisοindοle". Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMIR11.
Testo completoAbstract (sommario):
Depuis quelques décennies, les chimistes cherchent à toujours repousser les limites des stratégies de synthèse en développant des méthodologies toujours plus efficaces, plus simples et plus économes. Dans ce contexte, la fonctionnalisation directe de liaisons C—H catalysée par des métaux de transition constitue l’un des outils les plus puissants pour construire et fonctionnaliser des molécules simples mais aussi des édifices moléculaires de plus en plus complexes, avec une grande diversité de liaisons C—H, ces stratégies répondant également aux besoins actuels d’ouverture de l’espace chimique de fonctionnalisation de façon orthogonale. L’imidazoisoindole, hétérocycle tricyclique composé d’un noyau imidazole, est une plateforme pharmacologique très intéressante et présente des liaisons C—H avec des propriétés très diverses, mais aucune méthodologie de fonctionnalisation tardive de ces structures n’a encore été répertoriée dans la littérature. Ces travaux de thèse s’inscrivent dans ce contexte et présentent, (I) fort de l’expérience passée du laboratoire, une méthodologie robuste de synthèse à grande échelle d’imidazoisoindoles diversement substitués par activation C—H intramoléculaire pallado-catalysée ; (II) une extension des méthodologies standards de fonctionnalisation directe C2—H régiosélective de la série des 1,3-diazoles aux imidazo[5,1-a]isoindoles par catalyse coopérative palladium(0)-cuivre(I) ; (III) une méthodologie de mono-fonctionnalisation directe C(sp³)—H pallado-catalysée de la position benzylique des imidazo[2,1-a]isoindoles ; (IV) une étude préliminaire de la régiosélectivité observée lors de la borylation directe C(sp²)—H irido-catalysée des imidazo[2,1-a]isoindolesFor several decades, chemists constantly seek to push the limits of synthetic strategies by developing ever more efficient and more economical methodologies. In this context, transition metal-catalyzed direct functionalization of C—H bonds is one of the most powerful tools for constructing and funtionalizing simple molecules and ever more complex moieties, with a great diversity of C—H bonds. These strategies also answer the needs for the opening of the chemical space of functionalization. Imidazoisoindole, tricyclic heterocycle composed of an imidazole core, is a very interesting scaffold for biological activity and presents C—H bonds with very diverse properties, but late-functionalization methodology of these structures has yet to be listed in the literature. This work takes place in this context and presents, (I) based on past laboratory experience, a robust methodology to synthetize diversely substituted imidazoisoindoles at high scale by palladium-catalyzed intramolecular C—H activation ; (II) an extension of standard directC2—H functionalization of 1,3-diazole moieties applied to imidazo[5,1-a]isoindoles with a palladium(0)-copper(I) cooperative catalysis ; (III) a new methodology of direct C(sp³)—H palladium-catalyzed mono-functionalization at benzylic position of imidazo[2,1-a]isoindoles ; (IV) a preliminary study of the observed regioselectivity of iridium-catalyzed direct C(sp²)—H borylation of imidazo[2,1-a]isoindoles
19
Zakis, Janis Mikelis. "Catalyseurs d'iridium cyclométallés pour la borylation ortho-dirigée de C–H". Electronic Thesis or Diss., Strasbourg, 2024. http://www.theses.fr/2024STRAF006.
Testo completoAbstract (sommario):
Au cours des deux dernières décennies, la borylation C–H a continué d'évoluer, passant des premiers exemples de réactions stœchiométriques à la synthèse de blocs de construction à l'échelle du kilogramme.1 Plus récemment, l'accent a été mis sur la borylation dirigée permettant un meilleur contrôle de la régiosélectivité dans des molécules plus complexes (Figure 1B).2,3 Généralement, cela est réalisé par une conception astucieuse du ligand introduisant des groupements chélateurs sur le ligand permettant l'interaction ligand-groupe directeur du matériau de départ (Figure 1A, II). La deuxième approche consiste à concevoir des ligands hétérobidentés qui fonctionnent par la formation d'iridacycles insaturés permettant la coordination du groupe directeur (Figure 1B-III)4-6 Cependant, la comparaison directe entre différents groupes directeurs (GD) est rarement démontrée, ce qui rend difficile la prédiction de la réactivité dans des molécules complexes. Le précurseur métallique le plus utilisé [Ir(COD)OMe]2 est également sensible à l'air et à l'humidité, ce qui complique son utilisation pour le criblage à haut débit. Nous avons cherché à résoudre ces deux problèmes en développant des catalyseurs à base d'iridium hautement sélectifs et stables à l'air. En utilisant ces nouveaux catalyseurs, nous avons criblé une multitude de GD différents et nous avons réussi à fonctionnaliser des molécules complexes de manière prévisibleC–H borylation has continued to evolve from early examples of stoichiometric reactions to a method employed for building block synthesis on a kilogram scale. However, challenges remain for its wider application. We have developed new bis-cyclometallated iridium complexes exhibiting an improved reactivity and air-stability. These complexes have been used for the ortho-directed C–H borylation of arenes, heterocycles, and acrylamides, achieving average to high yields. By combining these new catalysts with high-throughput screening, we rapidly evaluated the reactivity of different directing groups, enabling predictions for the functionalization of substrates with multiple directing groups. Mechanistic studies revealed the details how these new bis-cyclometallated complexes are activated during the reaction. Subsequently, we investigated ligand free borylation and found a wide range of compatible substrates. We then investigated miniaturization of C-H borylation reactions and successfully conducted them on micromolar scale. By integrating our findings with those from the literature, we designed a screening platform comprising eight different reaction conditions. This platform was used to screen a vast array of small molecules, as well as more complex substrates. The results revealed differences between the catalytic systems and allowed us to successfully functionalize complex molecules. These findings highlight the widespread of ligand-free borylation as well as the limitations of the current state-of-the-art methods
20
Jamshaid, Talha. "Synthèse de latex magnétique submicronique et fonctionnalisé pour application en biocapteur". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1061/document.
Testo completoAbstract (sommario):
L'objectif de ce travail est de surmonter tous ces processus long et fastidieux comme la filtration et la centrifugation qui sont utilisées dans l'application in-vitro. En plus, ces particules qui sont appropriés pour une utilisation dans le laboratoire-sur une-puce et les biocapteurs systèmes sont produites. Les particules submicroniques magnétiques de latex (MLPs) avec la morphologie noyaucoque souhaité ont été préparées. L'huile dans eau (h/e) et l'émulsion magnétique (faitmaison) a été utilisé en tant que graine de polymérisation radicalaire en émulsion de styrène (St) en tant que monomère et agent de reticulation divenylbenzene (DVB) en présence de persulfate de potassium qu'initiateur. Les particules de la surface ont été fonctionnalisés avec du sulfate et des groupes carboxyliques en utilisant les initiateurs. Un nouveau biocapteur électrochimique de capacité basé sur de substrat de nitrure de silicium (Si3N4) combiné à des MLPs a été développé. MLPs avec terminaison acide carboxylique ont été liés de manière covalente à Si3N4 à travers des monocouches autoassemblées (SAMs) du silane-amine (3-aminopropyl) triéthoxysilane (APTES). Enfin les anticorps anti-ochratoxine A ont été immobilisés sur les MLPs par liaison amide. Mesures électrochimiques ont été effectuées en utilisant une analyse Mott-Schottky pour la détection de l'ochratoxine A (OTA). L'utilisation de l'application de dosage compétitif grà¢ce à l'immobilisation des quantités fixe d'antigène (SA2BSA) et d'anticorps (Ab 155) a été mesurée respectivement contre différentes concentrations de sulfamides pyridine (SPY), avec et sans utilisation de MLPs avec une fonctionnalité de groupe carboxylique. La sensibilité de Biocapteur a augmenté quand MLPs ont été utilisésObjective of this work is to overcome all those tedious and time consuming processes likefiltration and centrifugation which are used in in-vitro applications. Moreover, suchparticles which are suitable for use in lab-on-a-chip and biosensors systems are produced.Submicron magnetic latex particles (MLPs) with desired core-shell morphology wereprepared. Oil in water (o/w) magnetic emulsion (home-made) was used as seed of radicalemulsion polymerization of Styrene (St.) as a monomer and cross-linker divenylbenzene (DVB ) in the presence of potassium persulfate (KPS) and 4, 4'-azobis cyanopentanoic acid(ACPA) as an initiators. Particles surface was functionalized with sulfate and carboxylicgroups by using the initiators.A novel capacitance electrochemical biosensor based on silicon nitride substrate (Si3N4)combined with MLPs was developed. MLPs with terminated carboxylic acid werecovalently bonded to Si3N4 through a Self-Assembled Monolayers (SAMs) of the silaneamine(3- Aminopropyl) triethoxysilane (APTES). Finally anti-ochratoxin A antibodieswere immobilized on MLPs by amide bonding. Electrochemical measurements werecarried out using Mott-Schottky analysis for ochratoxin A (OTA) detection.Using application of competitive assay through immobilized fixed concentration of antigen (SA2BSA)and antibody (Ab 155) respectively was measured against different concentrations of sulfa pyridine(SPY), with and without use of MLPs with carboxylic group functionality. Biosensor sensitivityincreased, when MLPs were used
21
LENCI, ELENA. "Diversity-Oriented Synthesis of novel glyco- and peptidomimetic scaffolds". Doctoral thesis, 2017. http://hdl.handle.net/2158/1091042.
Testo completoAbstract (sommario):
After an impressive growth at the end of the last century, the number of new molecular entities launched on the market dramatically decreased in recent years. Thus, there is a need for efficient synthetic processes capable of generating an high number of different molecules, which differ not only for the appendages, but also for the molecular skeleton. In this context, Diversity-Oriented Synthesis (DOS) has proved to be very effective in the achievement of high quality small molecules collections for high-throughput screening and phenotypic assays and chemical genetics studies, leading to the discovery of new lead compounds. The aim of this thesis work is to apply the principles of the DOS to obtain densely functionalized molecular scaffolds, with potential glyco- and/or peptidomimetic moieties. In particular, in a first part, the synthesis of six skeletally different compounds starting from D-mannose has been discussed, together with their application in a phenotypic screening. This cell-based assay, combined with follow up synthesis and further biological studies, led to the discovery of the hexahydro-2H-furo[3,2-b][1,4]oxazine structure as an active modulator of MDA-MB-231 cell growth, through cytostatic effect. Then, the synthesis of a dipeptide isoster, the dihydropyrazinone skeleton, through morpholine acetal rearrangement has been developed. Finally, during a secondment activity of this PhD in the group of Prof. Darren J. Dixon at the University of Oxford, the generation of α-amino nitriles from tertiary amides and lactams was studied and applied in the late stage functionalization of drugs and natural products.
22
Zheng, Lei. "Noncovalent Functionalization of Latex Particles using High Molecular Weight Surfactant for High-Performance Coatings". 2019. https://scholarworks.umass.edu/masters_theses_2/813.
Testo completoAbstract (sommario):
The expected outcome of this project is to develop a general strategy to functionalize dispersions, by noncovalent adsorption of HMW surfactants, ultimately for applications such as hydrophobic coatings with high hiding power and hardness, improved mechanical properties via pigment-latex interactions, improved substrate adhesion or improved freeze-thaw stability. So far, we have produced poly (methyl methacrylate-co-butyl acrylate) latexes in the presence of HMW surfactants via emulsion polymerization and demonstrated stronger adsorption of HMW surfactants on particle surface than sodium dodecyl sulfate (SDS). In addition, we have developed surfactant-free latexes, poly (methyl methacrylate-co-butyl acrylate-co-methacrylic acid), as models for post functionalization with high molecular weight surfactants. The successful transfer of surfactants onto particle surface from liquid crystals was indicated by the increase in zeta potential and confirmed via chemical shifts variation in 1H NMR spectra. Additionally, the HMW surfactants were used for dispersing hydrophobic inorganic particles, such as hydrophobic carbon black, in aqueous phase, providing an indication of the general applicability and versatility of our approach.