Thesis (M.S.)--University of Wisconsin--Madison, 1942. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 14).

Thesis (Ph. D.)--Johns Hopkins University, 1915. / Biography.

Thesis (Ph. D.)--Johns Hopkins University, 1915. / Biography.

Les amines biogènes (AB) sont des substances physiologiquement actives résultant de la décarboxylation enzymatique des acides aminés libres. Elles participent, dans le corps, aux processus de transmissions d'informations et de régulation de fonctions physiologiques mais peuvent aussi, à doses élevées, avoir des effets néfastes pour la santé. De nombreuses AB sont répertoriées dans la littérature, telles que l'histamine, la cadavérine et la putrescine. Mais, seul le contrôle d'histamine dans la chair de certains poissons de la famille des scombridés est actuellement réglementée (CE n° 2073/2005). Du fait de cette réglementation, les techniques d'analyses chimiques de l'histamine sont largement documentées. Elles peuvent être semi-quantitatives (chromatographie sur couche mince) ou encore quantitatives (fluorescence moléculaire) mais, la chromatographie liquide haute-performance reste, à ce jour, l'unique méthode homologuée au niveau des instances de santé européenne. En marge de ces méthodes traditionnelles, l'enjeu d'un dispositif rapide, peu onéreux et permettant un contrôle plus systématique des aliments anime à la fois la communauté scientifique et le monde économique. Dans ce contexte, la pertinence à recourir à des Quantum Dots (QD) fonctionnalisés par un dérivé d'ortho-phthalaldéhyde (OPA) (utilisé en tant qu'agent de dérivation en fluorescence moléculaire pour les AB) a été posée. Lors de ce projet, deux éléments clés d'un tel dispositif ont été réalisés et caractérisés. Les premiers correspondent aux dérivés fonctionnalisés de l'OPA (4-Me-OPA et 4-HO-OPA). Ils ont été obtenus avec succès selon trois voies de synthèse. Les premières correspondent à des optimisations de synthèses référencées du 4-HO-OPA à partir d'alcool furfurylique ou du 3,4-diméthylphénol. Enfin, celle issue de l'acide 3-méthoxybenzoïque est une adaptation d'une synthèse référencée du 4-MeO-OPA. Dans un second temps, les propriétés du 4-MeO-OPA en tant qu'agent de dérivation vis-à-vis de l'histamine ont été évaluées et comparées à celles de l'OPA. Pour cela, les conditions optimales de complexation ont été étudiées par spectroscopies Ultra-Violet (UV) et de fluorescence moléculaire. Les seconds composants du dispositif sont des nanostructures fluorescentes (QD) dont les propriétés d'émission de fluorescence sont modulables. Notre choix s'est porté sur les QD hydrosolubles de cadmium et sélénium stabilisés par de l'acide mercaptosuccinique. Ces derniers ont été synthétisés par trois modes d'activation (thermique, micro-ondes, ultrasons) et caractérisés par diffractométrie de rayons X, spectrométrie à plasma à couplage inductif, spectroscopies UV et de fluorescence moléculaire. En conclusion, deux entités, le 4-HO-OPA et des QD possédant des ligants de type mercaptosuccinique, ont été réalisées en vue de la mise en place d'un dispositif innovant d'analyse d'histamine. / The biogenic amines (BA) are physiologically active substances resulting from the enzymatic decarboxylation of free amino acids. In the body, they are involved in the transmission of informations and in regulating physiological functions but, at high levels, they can also have damaging health effects. Many BA are recorded in literature, such as histamine, cadaverine and putrescine. Currently, the control of histamine in fish flesh is only regulated in the case of some Scombridae species (CE N° 2073/2005). As a consequence, histamine chemical analysis techniques are widely documented. They can be semi-quantitative (thin layer chromatography) or quantitative (molecular fluorescence). At present, high-performance liquid chromatography remains the only approved method by public heath authorities. Next to the commonly used methods, the challenge of a fast inexpensive system that allows a more systematic control of food animates both the scientific community and the economic world. In this context, a study of the relevance of using Quantum Dots (QD) functionalized by an ortho-phtalaldehyde (OPA) derivative (OPA), used as molecular fluorescence derivation agent for BA, was undertaken. During this project, two key elements of the system were realized and characterized. The first corresponds to OPA functionalized derivates (4-MeO-OPA and 4-HO-OPA). They have been successfully achieved through three synthesis ways. The first two are optimizations of 4-HO-OPA referenced syntheses from furfuryl alcohol or 3,4-dimethylphenol. Finally, the last one uses 3-methoxybenzoic acid and is a 4-Me-OPA reference synthesis adaptation. In a second part, the 4-MeO-OPA properties as a bypass agent for histamine analysis were evaluated and compared with OPA ones. In this case, optimal complexation conditions were analyzed by ultra-violet (UV) and molecular fluorescence spectroscopies. The second components are QD, which are fluorescent nanostructures with molecular properties. We selected water soluble cadmium and selenium QD which were stabilized by mercaptosuccinic acid. They were synthesized by three activation modes (thermal, microwave, ultrasound) and characterized by X-ray diffractometry, inductively coupled plasma spectrometry, UV spectroscopy and molecular fluorescence. In conclusion, two entities, 4-HO-OPA and QD, both having a mercaptosuccinic-type shell, were created as the innovative set up for histamine analysis.

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N,N-Diethyl-O-sulfamate (OSO2NEt2) has been established as a new directed metalation group (DMG). Its similarity to the established O-carbamate DMG has prompted investigation into its potential as a partner in transition metal-catalyzed cross coupling reactions with aryl organometallics with the intention to develop a new route to contiguously substituted aromatics. Furthermore, aryne formation of ortho-magnesiated O-sulfamates at higher temperatures can be trapped with furan to afford cycloaddition products having substitution patterns difficult to prepare by similar methods. Schumanniophytine is a structurally interesting alkaloid possessing anti-viral activity. Thus far, only a single synthesis has been reported which proceeds in poor yield and offers little opportunity for the synthesis of structurally diverse schumanniophytine derivatives. Herein we report the total synthesis of schumanniophytine by a directed ortho metalation (DoM) – cross coupling strategy using a key directed remote metalation (DreM) step. The synthesis proceeds in 10 steps with 24% overall yield, offering plenty of opportunity for structural variation. Naturally abundant chromone derivatives contain an array of biological activities. The ability to prepare differentially substituted chromones in a rapid manner is of great interest in medicinal chemistry. Reported is a general and divergent synthesis of chromone carboxamides, from easily prepared 2-but-2-ynoyl aryl O-carbamates. The reaction proceeds by carbamoyl translocation and anionic Fries rearrangement followed by Michael addition of the initially generated cumulenolate for which evidence is provided. Further metalation and borylation reactions of the synthesized compounds allow the regioselective construction of polysubstituted chromones. / Thesis (Ph.D, Chemistry) -- Queen's University, 2007-11-30 11:18:51.673

The synthesis of compounds containing α-arylated quaternary stereogenic centres is a significant synthetic challenge. This thesis describes the development of an organocatalytic methodology for the direct construction of this motif through the Michael addition of carbon-centered pro-nucleophiles to highly reactive and unstable ortho-benzoquinones. Proof-of-principle for the base catalysed Michael addition to ortho-quinones was established with stable 1,2-naphthoquinone (Chapter 2), however typical orthobenzoquinones were found to be too unstable to use in this process. Accordingly an oxidative coupling strategy was developed for in-situ generation of the obenzoquinone electrophile (Chapter 3.1). The base catalysed Michael addition followed by aromatisation allows for the direct construction of arylated quaternary stereocentres. An asymmetric variant was also developed by replacing the base catalyst with a cinchona alkaloid derived organocatalyst, up to 82% ee was achieved (Chapter 3.2).The methodology was then applied to the racemic total synthesis of the amaryllidaceae alkaloids powelline and buphanidrine (Chapter 4). The oxidative coupling methodology allowed rapid construction of the sterically congested arylated quaternary stereocentre in the key step of the syntheses, which were then completed in 13 and 14 steps respectively in 6% overall yield. Employing a quinidine derived organocatalyst in the oxidative coupling step gave the arylated product in 57% yield (3 steps) and 70% ee (Chapter 5). However, the enantioselective total synthesis was thwarted by racemisation during the Dieckmann-type cyclisation for the formation of enol ether 212 and an alternative synthetic strategy will berequired to synthesise the enantiopure alkaloid.

Für die Speicherung und den Transport von Wasserstoff ist die Verflüssigung und anschließende Lagerung in flüssiger Form wegen der deutlich vergrößerten Dichte oft die wirtschaftlichste Lösung. Bei Umgebungstemperatur besteht Wasserstoff zu 75% aus Orthowasserstoff und 25% aus Parawasserstoff. Bei der Verflüssigung ist zu beachten, dass es unterhalb von etwa 250 K zu einer exothermen Umwandlung von Ortho- zu Parawasserstoff kommt. Dadurch wird der Energieaufwand zur Verflüssigung vergrößert. Die Entdeckung, dass es die Allotrope Ortho- und Parawasserstoff gibt, spielte eine wichtige Rolle bei der Entwicklung der Quantenphysik in den zwanziger und dreißiger Jahren des 20. Jahrhunderts. Heute sind vor allem die technischen Aspekte bei der Verflüssigung von Bedeutung. Im wissenschaftlichen Schrifttum fehlte bisher eine zusammenfassende Darstellung der physikalischen und technischen Aspekte. Diese Lücke soll mit dieser Arbeit geschlossen werden. Es werden die Aspekte der Theorie der Unterschiede der beiden Wasserstoffallotrope Orthowasserstoff und Parawasserstoff, die Umwandlung von einem Allotrop in das andere, die Auswirkungen der Unterschiede auf die Stoffgrößen, die mögliche Messung der Anteile, die Selbstumwandlung, die gewollte und ungewollte katalytische Umwandlung sowie die großtechnischen Anwendungen behandelt. Im Rahmen der Arbeit wurde insbesondere die Umwandlung an dem kommerziell erhältlichen Katalysatormaterial Eisenoxid sowie die katalytische Umwandlung an Adsorptionsmaterialien zur kryogenen Wasserstoffspeicherung und Wasserstoffreinigung untersucht. Neue Erkenntnisse der Arbeit sind zum einen ein verbessertes Verständnis der Aktivierung des kommerziell erhältlichen und eingesetzten Ortho-Para-Katalysators Eisenoxid, verbunden mit einer kostenoptimierten Möglichkeit der Aktivierung und zum anderen die ersten Messungen der katalytischen Aktivität neuer kryogener Speichermaterialien auf Basis der Wasserstoffadsorption.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

¤@.Pyrolysis of 2-(N,N-dimethylamino)styrylarenes (29a-e) and 2-(N,N- benzylmethylamino)styrylarenes (30a-f) both gave 2-(ar-2-yl)- benzo[b]arenes 35a-f, 39a-e, their isomers 36a-e, 40a-e and the other products. On the other hand, photolysis of 29a-e gave electrocyclic products 2, 57b-e and 22a-e, respectively. However photolysis of 30a-f only gave the complicated and unknown compounds. ¤G.Pyrolysis of benzoic 1,3-dimethyl-2-indolyl anhydride (54) gave (1,3-dimethylindol-2-yl)phenylmethanone (63), 1,3-dimethylindole (65) and bis(1,3-dimethylindol-2-yl)methanone (66) as the main products.