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Die Wirkung von Bencyclan, Flunarizin und Naftidrofuryl auf einen experimentell erzeugten DauernystagmusSchmidtmayer, Erich Klaus, January 1979 (has links)
Thesis (doctoral)--Ludwig Maximilians-Universität zu München, 1979.
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Surface-enhanced Raman spectroscopy (SERS) for the qualitative analysis of synthetic piperazinesWard, Jessamyn 02 November 2017 (has links)
Designer drugs are some of the most commonly abused substances in the world. They are synthesized through slight chemical modifications of existing substances, evading the law while maintaining the desired effects of the pharmaceutical or illicit substance. These drugs are often marketed as “herbal” or “natural,” but are fully synthetic. Due to their constant, rapid emergence, there is a need for a rapid method of identification, both in the field as well as in the laboratory.
One group of these designer drugs are synthetic piperazines. Named for the piperazine ring found in their chemical structures, synthetic piperazines are central nervous system stimulants that have the reputation of mimicking the psychoactive effects of the illicit compounds amphetamine and 3, 4-methylenedioxymethampetamine (MDMA). Over the past 10 years, synthetic piperazine cases submitted to forensic laboratories in the United States have greatly increased, including a 30-fold increase between 2007 and 2009 alone.
Surface enhanced Raman spectroscopy (SERS) was investigated as a method for the rapid qualitative analysis of synthetic piperazines. SERS is a type of vibrational spectroscopy, which utilizes the interaction of light and matter to elucidate details of the
chemical structure of a molecule. SERS combines laser spectroscopy with the optical properties of metallic nanostructures, resulting in strongly enhanced signals from the Raman scattering of light. Each chemical structure will give a unique SERS spectrum and this, coupled with the minimal-to-no sample preparation and the portability of a SERS instrument, makes SERS a strong candidate for the identification of not only synthetic piperazines, but all designer drugs.
To evaluate the use of SERS for the qualitative analysis of synthetic piperazines, eight synthetic piperazines were adsorbed onto a SERS substrate. The interaction with the gold nanoparticles enhanced the Raman scattering for all eight of the synthetic piperazines and SERS spectra were obtained. All eight drugs were found to give a robust and reproducible signal, requiring a fewer number of scans, less laser power, and less time for analysis compared with traditional Raman spectroscopy. When compared with traditional Raman spectra, the synthetic piperazines demonstrated sensitivity enhancement factors of up to 10^8 using SERS.
A partial least squares-discriminant analysis (PLS-DA) statistical model was built and used to evaluate the analytical sensitivity and specificity of the SERS method. The PLS-DA model helped determine a limit of detection of 10 μg/mL of BZP. All eight synthetic piperazines could be identified by the statistical model below an error rate of 20% when compared to each other- a strong indication of a method with high specificity.Through this research, it has been demonstrated that SERS can be applied efficiently as a qualitative technique for the analysis of synthetic piperazines.
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Type-5 phosphodiesterase inhibition in the prevention of doxorubicin cardiomyopathyFisher, Patrick William, January 1900 (has links)
Thesis (Ph.D.) -- Virginia Commonwealth University, 2005. / Title from title-page of electronic thesis. Prepared for: Dept. of Physiology. Bibliography: p. 81-91.
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Treatment of experimental hemorrhagic and burn shock with 1-ethanesulfonyl-4-ethyl piperazineJordan, Steven Ernest, January 1954 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1954. / Typescript (carbon copy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 78-85).
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Investigation in stability of eight synthetic piperazines in human whole blood under various storage conditions over timeLau, Timothy Wan Tsun 13 July 2017 (has links)
Over the past decade, synthetic piperazines have been associated with multiple fatalities and was one of the top 25 identified drugs in 2011. While circumventing legislative controls and preventing the detection in standard drug tests, synthetic piperazine derivatives are encountered in forensic casework as “legal” alternatives to ecstasy (3,4-methylenedioxymethamphetamine). These chemically-produced compounds share very similar pharmacological and psychological effects with ecstasy which in turn has led to their popularity as “party pills”. The long-lasting duration of synthetic piperazines, especially when 1-benzylpiperazine (BZP) is mixed with 1-(3-trifluoromethylphenyl)-piperazine (TFMPP), has also made them desirable to drug users to receive enhanced hallucinogenic effects.
Although most methods are optimized to accurately quantify the amount of drugs in biological specimens submitted for forensic toxicology testing, unforeseeable challenges may arise to complicate the analysis such as postmortem redistribution, enzymatic reactions, the presence of bacterial activities, chemical and matrix interferences as well as the lack of reference materials. Thus, the purpose of this research was to investigate the stability of synthetic piperazines in human whole blood under various storage conditions and time ranges. A total of eight synthetic piperazines were assessed on their degrees of degradation using a Shimadzu Ultra-Fast Liquid Chromatography (UFLC) with SCIEX 4000 Q-Trap Electrospray Ionization Tandem Mass Spectrometry in positive ionization mode. These analytes included: 1-benzylpiperazine (BZP), 1-(4-fluorobenzyl)-piperazine (FBZP), 1-(4-methylbenzyl)-piperazine (MBZP), 1-(4-methoxyphenyl)-piperazine (MeOPP), 1-(para-fluorophenyl)-piperazine (pFPP), 1-(3-chlorophenyl)-piperazine (mCPP), 2,3-dichlorophenylpiperazine (DCPP), and 1-(3-trifluoromethylphenyl)-piperazine (TFMPP).
Individual unknown samples were prepared by spiking certified reference standards (Cayman Chemical, Ann Arbor, MI, U.S.A.) of each synthetic piperazine into certified drug-free human whole blood (UTAK Laboratories, Inc., Valencia, CA, U.S.A.) independently at 1000 ng/mL. To closely monitor the stability of each compound and potential drug-drug interactions, mixed samples consisted of all eight piperazines were also stored at room temperature (~20°C), 4°C and -20°C for one, three, six, nine and twelve months in dark sealed containers. Solid phase extraction (SPE) was performed to remove unwanted components prior to the injection into the LC system. Drug of Abuse (DAU) mixed-mode copolymeric columns (Clean Screen®, UCT Inc., Levittown, PA, U.S.A.) were utilized with a positive pressure manifold rack followed by evaporating to dryness with low heat at 65°C. All samples were then reconstituted with 250 µL of 50:50 mixture of methanol and 2mM ammonium formate buffer with 0.2% formic acid (Fisher Scientific, Waltham, MA, U.S.A.).
Analysis was performed in triplicate using a reversed-phase column (Kinetex® F5, Phenomenex®, Torrance, CA, U.S.A.) with a binary gradient of a 2mM ammonium formate buffer with 0.2% formic acid and methanol with 0.1% formic acid. The total run time was 11.5 minutes including equilibration and the flow rate was 0.4 mL/min. Three internal standards including BZP-d7, mCPP-d8 and TFMPP-d4 (Cerilliant, Round Rock, TX, U.S.A) were used to generate calibration curves that were ranged from 20 ng/mL to 2000 ng/mL.
Results revealed that BZP, MBZP and FBZP were more stable than phenyl piperazines over time under all storage conditions, in which MBZP was consistently more stable and still had more than 70% remaining after 12 months. Data showed a smaller degree of degradation when samples were kept frozen or refrigerated; whereas storing at room temperature should be avoided to ensure minimal degradation and detrimental impacts on stability of piperazine compounds. For crime laboratories that are facing backlog situations, case samples with synthetic piperazines should be kept frozen or refrigerated even for time period as short as 30 days or less. However, storing them for too long will clearly affect the quantitation accuracy because phenyl piperazines are more susceptible to degrade completely after six months regardless of storage conditions. Additionally, matrix interference was present due to the outlier of MBZP quantified on Day 270. Drug-drug interaction was also observed in the analyte mixture but the exact stability pattern of phenyl piperazines when mixed together could not be determined from this data set alone due to discrepancies observed on Day 91 and 270.
This research project had shown a solid method to examine how quickly or slowly synthetic piperazines degrade in blood at different storage conditions. To further this study, it would be also important to evaluate the number of freeze-thaw cycles on each specimen in order to minimize the effect of non-metabolic degradation.
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The synthesis, analysis and characterisation of piperazine based drugsKuleya, Chipo January 2014 (has links)
This study developed a GC-MS method for the simultaneous detection of piperazines and congeners in street samples of amphetamine type stimulants. This research investigated the clandestine routes of synthesis and chemical profiles of phenylpiperazines, represented by 1- (4-fluorophenyl)piperazine (4-FPP) and 1-(3-trifluoromethylphenyl)piperazine (3-TFMPP). These drugs are part of the increasingly prevalent illicit new psychoactive substances. The presence of (2, 3, 4) FPP and (2, 3, 4) TFMPP positional isomers has been identified by other researchers as a limitation due to their similar chemical profiles. The method was optimized and confirmed as compliant with the International Conference on Harmonisation and the Center for Drug Evaluation and Research guidelines on validation. 4- FPP and 3-TFMPP were synthesised using potential routes for clandestine laboratories. Simple extraction and analysis of 11 street samples was conducted using the method developed. Furthermore, the stability of 22 drugs during analysis was investigated. Limits of detection were in the range 5 – 1.95ng/mL free base on column. The synthesised samples were identified as 4-FPP and 3-TFMPP. Several impurities were observed in the synthesised samples, which were identified and categorised as residual reactants, isomers of 4-FPP and of 3-TFMPP and by-products of synthesis. The percentage yields of the synthesised samples obtained were up to 82.4% 4-FPP and 78.7% 3-TFMPP. The street samples were found to contain MDMA, 3-TFMPP, BZP, caffeine, ephedrine and other impurities. The analytical method simultaneously separates 19 of the most common drugs found in piperazine samples and achieves for the first time the GC-MS separation of (i) 2-FPP, 3-FPP and 4-FPP and (ii) 2-TFMPP, 3-TFMPP and 4-TFMPP at the same time from a sample matrix containing all the 19 compounds. This method provides operational laboratories with a more effective method for the chemical characterisation of street samples of piperazines and also provides novel stability data.
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Atividade anti-inflamatória e antinociceptiva de 4-((1-fenil-1h-pirazol-4-il) metil) piperazina-1-carboxilato: um novo derivado piperazínico / Antinociceptive and anti-inflamatory activities of 4-[(1-fenil-1h-pirazol-4-il) methyl] piperazine-1-carboxiylic acid ester: a new piperazine derivateSilva, Daiany Priscilla Bueno da 25 February 2015 (has links)
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Previous issue date: 2015-02-25 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The piperazines derivatives are an important class of chemical compounds with a broad spectrum of biological activities such as anti-infectious activity, anti-carcinogenic, anti-nociceptive, anti-hypertensive, anxiolytic and vasorelaxant and are attractive candidates for development of new analgesics and anti-inflammatories drugs. The aim of this study was evaluate the effects of piperazine compound LQFM-008 (4-[(1-phenyl-1H-pyrazol-4-yl) methyl]1-piperazine carboxylic acid ethyl ester) in acute tests of nociception and inflammation and characterize that the mechanisms are involved in the antinociceptive effect. For this study were used male mice weighing between 25 and 35g. In the formalin test, the treatments with LQFM-008 at doses of 48 and 96 μmol/kg (p.o.) reduced the licking time at both neurogenic and inflammatory phases of this test. The anti-inflammatory activity was confirmed, since LQFM-008 at doses of 48 and 96 μmol/kg (p.o.) reduced the formation of paw edema induced by carrageenan at all hours of the test and LQFM-008 in pleurisy test at dose of 96 μmol/kg (p.o.) also reduced leukocyte migration and protein exudation. In the tail-flick and the hot plate tests, the treatment with LQFM-008 at doses of 48 and 96 μmol/kg (p.o.) increased the latency to thermal stimulus, suggesting the involvement of central mechanisms in the antinociceptive effect LQFM-008. The pre-treatment of animals with naloxone (7.5 μmol/kg s.c.) reversed the antinociceptive effect of LQFM-008 only in the first phase of the formalin test, however, the pre-treatment with NAN-190 (1.3 μmol/kg i.p.) and PCPA (500 μmol/kg i.p.) reversed the antinociceptive effect of LQFM-008 in both phases of the test. Thus, the piperazine derivative LQFM-008 exhibit antinociceptive and anti-inflammatory activities in acute test and the antinociceptive effect is resulting from a central action with involvement of opioid receptors and the serotonin pathway. / Os derivados piperazínicos constituem uma importante classe de compostos químicos com largo espectro de atividades biológicas, tais como atividade anti-infecciosa, anti-cancerígena, antinociceptiva, anti-hipertensiva, vasorrelaxante e ansiolítica, tornando-se candidatos atrativos para desenvolvimento de novos fármacos analgésicos e anti-inflamatórios. O objetivo do presente trabalho foi avaliar os efeitos do composto piperazínico LQFM-008 (4-((1-fenil-1H-pirazol-4-il) metil) piperazina-1-carboxilato) em testes agudos de nocicepção e inflamação, buscando caracterizar quais os mecanismos de ação estariam envolvidos no efeito antinociceptivo. Para este estudo foram utilizados camundongos machos, pesando entre 25 e 35g. No teste da formalina os tratamentos com LQFM-008 nas doses de 48 e 96 μmol/kg (v.o.) reduziram o tempo de reatividade à dor tanto na fase neurogênica quanto na fase inflamatória do teste. A atividade anti-inflamatória foi confirmada, uma vez que LQFM-008 nas doses de 48 e 96 μmol/kg (v.o.) reduziu a formação do edema de pata induzido por carragenina em todas as horas deste teste e no teste de pleurisia LQFM-008 na dose de 96 μmol/kg também reduziu a migração de leucócitos e a exsudação proteica. Nos testes de flexão de cauda e da placa quente, o tratamento com LQFM-008 48 e 96 μmol/kg (v.o.) aumentou a latência ao estímulo térmico, sugerindo o envolvimento de mecanismos centrais no efeito antinociceptivo de LQFM-008. O pré-tratamento dos animais com naloxona (7,5 μmol/kg s.c.) reverteu o efeito antinociceptivo de LQFM-008 apenas na primeira fase do teste da formalina, no entanto, os pré-tratamentos com NAN-190 (1,3 μmol/kg i.p.) e PCPA (500 μmol/kg i.p.) reverteram o efeito antinociceptivo de LQFM-008 em ambas as fases do teste. Assim o derivado piperazínico LQFM-008 apresenta atividade antinoceptiva e anti-inflamatória em testes agudos, sendo efeito antinociceptivo decorrente de uma ação central com envolvimento dos receptores opióides e da via serotoninérgica.
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Catalytic transformations of glycerol via hydroxyacetone into nitrogen heterocycles of industrial interestMazarío Santa-Pau, Jaime 17 January 2022 (has links)
[ES] La presente tesis doctoral aborda el desarrollo de nuevos procesos catalíticos centrados en la valorización del glicerol, subproducto principal en la síntesis de biodiesel. El objetivo principal del trabajo consiste en utilizarlo como fuente de carbono para la producción de heterociclos nitrogenados de interés industrial, en concreto, para la producción de 2-metilpiperazina y 2-metilpirazina. Debido a la baja reactividad del glicerol y las drásticas condiciones de reacción que serían necesarias para llevar a cabo las transformaciones a estos heterociclos, se ha planteado como paso previo el estudio de la optimización y el entendimiento del proceso de deshidratación selectiva de glicerol a hidroxiacetona (o acetol). A través de la obtención de este compuesto intermedio, se han podido desarrollar procesos de producción de los heterociclos nitrogenados eficientes y selectivos, en condiciones de reacción moderadas. A este respecto, los precursores de hidrotalcitas del tipo Cu-Mg-Al dan lugar a una familia de materiales basados en óxidos mixtos Cu-Mg-Al capaces de llevar a cabo la deshidratación selectiva de glicerol a acetol en continuo con rendimientos del ¿40%. Además, estos catalizadores son estables durante más de 8 horas, mostrando también excelente capacidad de regeneración y reusabilidad. Del mismo modo, la combinación de centros ácido-base y redox exhibida por estos materiales ha permitido, a través de la combinación de estudios catalíticos y de caracterización, avanzar en el estado del arte en lo que respecta a la comprensión de esta reacción de deshidratación catalítica de glicerol. De esta forma, se ha podido comprobar el papel fundamental de las especies de Cu y, en concreto de las especies Cu(I) presentes en los catalizadores, en la generación de gliceraldehido como intermedio clave para la producción de acetol. Del mismo modo, los centros ácidos del catalizador facilitan la primera adsorción del glicerol, acelerando así la reacción. No obstante, la necesidad de alcanzar productividades de acetol más elevadas para asegurar el éxito de la estrategia global motivó el desarrollo y estudio, en este proceso de deshidratación selectiva de glicerol en continuo, de una segunda familia de catalizadores basados en óxido de cobre soportado sobre diferentes óxidos metálicos (SiO2, Al2O3 y ZrO2), combinando centros ácidos de Lewis y una alta exposición del Cu. La adecuada selección y optimización de estos materiales lleva a lograr, con varios de ellos, rendimientos del 60% a acetol con concentraciones de glicerol en la alimentación mucho más elevadas. Una vez establecidos varios sistemas catalíticos para la producción de acetol, se abordó la producción de los heterociclos nitrogenados de interés a partir de la combinación de esta molécula con etilendiamina. En concreto, el catalizador Pd/TiO2-Al2O3 tiene alta actividad específica hacia la formación de 2-metilpiperazina (80% de rendimiento), gracias a su elevada exposición de centros de Pd insaturados, crítica para activar el doble enlace C=N y así proceder a la hidrogenación de las iminas intermedias. En segundo lugar, el catalizador CuO/Al2O3-npw, muestra rendimientos del 50% a la 2-metilpirazina, siendo posible alcanzar valores cercanos al 60% cuando se usa el método de precipitación-deposición por micelas en fase reversa para incorporar las nanopartículas de CuO. Finalmente, se llevó a cabo una prueba de concepto para la síntesis de 2-metilpirazina a partir de glicerol en un reactor multi-lecho especialmente diseñado para realizar las dos etapas del proceso en "one-pot" con el mismo catalizador basado en CuO-soportado, obteniéndose resultados prometedores. En definitiva, se han establecido dos nuevas rutas catalíticas para la producción de heterociclos nitrogenados con glicerol como la principal fuente de carbono a través de su derivado acetol, abriéndose así nuevas perspectivas en el campo de la valorización sostenible de moléculas derivadas de biomasa. / [CA] La present tesi doctoral aborda el desenvolupament de nous processos catalítics centrats en la valorització del glicerol, subproducte principal en la síntesi de biodièsel, utilitzant-lo com a font de carboni per a la producció d'heterocicles nitrogenats d'interès industrial. En concret, per a la producció de 2-metilpiperazina i 2-metilpirazina. A causa de la baixa reactivitat del glicerol i les dràstiques condicions de reacció que serien necessàries per a dur a terme les transformacions a aquests heterocicles, s'ha plantejat com a pas previ un estudi detallat escometent l'optimització i l'enteniment del procés de deshidratació selectiva de glicerol a hidroxiacetona (o acetol). A través de l'obtenció d'aquest compost intermedi, s'han desenvolupat processos de producció dels heterocicles nitrogenats eficients i selectius, en condicions de reacció moderades. Referent a això, els precursors hidrotalcítics Cu-Mg-Al donen com a resultat una família de materials basats en òxids mixtos Cu-Mg-Al capaços de dur a terme la deshidratació selectiva de glicerol a acetol en continu amb rendiments del 40%. Així mateix, aquests catalitzadors són estables durant més de 8 hores, mostrant a més una excel·lent regenerabilitat i reusabilitat. De la mateixa manera, la combinació de centres àcid-base i redox exhibida per aquests materials ha permès, a través de la combinació d'estudis catalítics i de caracterització, avançar significativament en l'estat de l'art pel que fa a la comprensió d'aquesta reacció catalítica. D'aquesta manera, s'ha pogut comprovar el paper fonamental del Cu i, en concret del Cu(I), en la generació de gliceraldehid com a intermedi de reacció clau. Per altra banda, els centres àcids del catalitzador faciliten la primera adsorció del reactiu, accelerant així la reacció. No obstant això, la necessitat d'aconseguir productivitats de acetol més elevades per a assegurar l'èxit de l'estratègia global va motivar l'ús, en aquest procés de deshidratació selectiva de glicerol en continu, d'una segona família de catalitzadors basats en òxid de coure suportat sobre diferents òxids inorgànics d'alta àrea (SiO2, Al2O3 i ZrO2), combinant centres àcids de Lewis i una alta exposició del Cu. L'adequada selecció i optimització d'aquests materials aconsegueix, amb alguns d'ells, rendiments del 60% a acetol amb concentracions de glicerol en l'alimentació molt més elevades. Una vegada establits diversos sistemes catalítics per a la producció d'acetol, es va abordar la producció dels heterocicles nitrogenats d'interès a partir de la combinació d'aquesta molècula amb etilendiamina. En concret, el catalitzador Pd/TiO2-Al2O3 té una alta activitat específica cap a la formació de 2-metilpiperazina (80% de rendiment), gràcies a la seua elevada exposició de centres de Pd insaturats, crítica per a activar el doble enllaç C=N i així procedir a la hidrogenació de les imines intermèdies. En segon lloc, s'ha pogut comprovar que, en presència d'un catalitzador principalment àcid contenint Cu, és possible realitzar la dehidrociclació d'acetol amb etilendiamina per a obtindre 2-metilpirazina i altres alquilpirazinas. Concretament, el catalitzador CuO/Al2O3-npw, mostra rendiments del 50% a la 2-metilpirazina, sent possible aconseguir valors pròxims al 60% quan s'utilitza el mètode de precipitació-deposició per micel·les en fase revessa per a incorporar les nanopartícules de CuO. Finalment, es va dur a terme una prova de concepte per a la síntesi de 2-metilpirazina a partir de glicerol en un reactor multi-llit especialment dissenyat per realitzar les dues etapes del procés en "one-pot" amb el mateix catalitzador basat en CuO-suportat, amb resultats prometedors. D'aquesta manera, s'han establit dues noves rutes catalítiques per a la producció d'heterocicles nitrogenats amb glicerol com a la principal font de carboni, a través del seu derivat acetol obrint així noves perspectives en l'àmbit de la valorització sostenible de les molècules derivades de la biomassa. / [EN] This doctoral thesis addresses the development of new catalytic processes centered on glycerol valorization, which is the main by-product of biodiesel synthesis. In this sense, the main aim focused on using it as a carbon source to generate nitrogen heterocycles of industrial interest, specifically, to produce 2-methylpiperazine and 2-methylpyrazine.
Due to the low reactivity of glycerol and the severe reaction conditions necessary to carry out the transformations towards these N-heterocycles, previous detailed research to optimize and understand the selective dehydration process of glycerol to hydroxyacetone (or acetol) was undertaken. Through obtaining this intermediate compound, it has been possible to develop efficient and selective nitrogen heterocycles production processes, under moderate reaction conditions.
In this regard, Cu-Mg-Al hydrotalcite precursors give rise to a family of materials based on Cu-Mg-Al mixed oxides capable of carrying out the selective dehydration of glycerol to acetol continuously with yields of 40%. In addition, these catalysts are stable for more than 8 hours under operational conditions, showing excellent regeneration capacity and reusability.
In the same way, through the combination of catalytic and characterization studies, the interesting mix of acid-base and redox centers exhibited by these materials has allowed for advancing significantly in the state of the art regarding understanding this glycerol catalytic dehydration reaction. Hence, it has been possible to verify the fundamental role of Cu species and, specifically, Cu(I) species present in the catalysts, in the generation of glyceraldehyde as a critical reaction intermediate for acetol production. Similarly, the acid centers of the catalyst facilitate the first adsorption of glycerol, thus accelerating the reaction.
However, the need to achieve higher acetol productivities from glycerol to stand a chance to succeed in the overall strategy motivated the development and study of a second family of catalysts based on copper oxide supported on different metal oxides (SiO2, Al2O3 and ZrO2) combining Lewis acid centers and high Cu exposure. The proper selection and optimization of these materials lead to reaching, with several of them, yields of 60% to acetol with much higher glycerol concentrations in the starting feed.
Once several catalytic systems had been established to produce acetol, the generation of the nitrogen heterocycles of interest from the combination of this molecule with ethylenediamine was investigated. Specifically, the Pd/TiO2-Al2O3 catalyst presents high specific activity when forming 2-methylpiperazine (80% yield). These excellent results could be attributed to the enhanced exposure of unsaturated Pd centers observed in this material, critical for activating the C=N double bond and thus proceeding to the hydrogenation of the intermediate imines. Secondly, the CuO/Al2O3-npw catalyst yields 50% to 2-methylpyrazine, reaching values close to 60% when the precipitation-deposition method by micelles in reverse phase is used to incorporate the CuO nanoparticles. Finally, a proof of concept of 2-methylpyrazine synthesis starting from glycerol by using a specially designed multi-bed catalytic reactor to perform the two-steps process in one-pot with the same CuO-supported catalyst was assayed, with promising results.
In summary, two new catalytic routes have been established to produce nitrogen heterocycles with glycerol as the main carbon source through its derivative hydroxyacetone, thus opening new perspectives in the field of sustainable valorization of biomass-derived molecules. / Mazarío Santa-Pau, J. (2021). Catalytic transformations of glycerol via hydroxyacetone into nitrogen heterocycles of industrial interest [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/179915 / TESIS
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STAT3 contributes to resistance towards BCR-ABL inhibitors in a bone marrow microenvironment model of drug resistance in chronic myeloid leukemia cells /Bewry, Nadine N. January 2009 (has links)
Dissertation (Ph.D.)--University of South Florida, 2009. / Includes vita. Includes bibliographical references. Also available online.
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STAT3 contributes to resistance towards BCR-ABL inhibitors in a bone marrow microenvironment model of drug resistance in chronic myeloid leukemia cellsBewry, Nadine N. January 2009 (has links)
Dissertation (Ph.D.)--University of South Florida, 2009. / Title from PDF of title page. Document formatted into pages; contains 149 pages. Includes vita. Includes bibliographical references.
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