Dissertations / Theses on the topic 'Amines'
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Sandford, Graham. "Some amine hydrofluorides and amines in organofluorine chemistry." Thesis, Durham University, 1991. http://etheses.dur.ac.uk/6209/.
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Kargina, Irina. "Topochemical reactions of amines and amides with titanium and vanadium oxychlorides." Thesis, University of Ottawa (Canada), 1995. http://hdl.handle.net/10393/10109.
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The intercalation of primary, secondary, tertiary, and aromatic amines into layered TiOCl have been investigated by a variety of methods. The intercalation reaction does not appear to be a redox process. A key step for intercalation of amines into host TiOCl is proposed to be a coordination via nitrogen lone electron pair to Ti$\sp{3+}$ metal centres. Subsequent substitution of the interlayer chloride ions of TiOCl by the amine molecules is strongly dependent on the properties of the organic compounds and their ability to form ammonium salts. Based on X-ray diffraction, fluorescence, elemental analysis and thermal analysis, a model for the interaction of amines with TiOCl is proposed. The intercalation of primary, secondary, and tertiary amides into TiOCl and VOCl have been studied. A redox intercalation process is ruled out by using variety of amides with a range of redox potentials. The proposed interaction of intercalated amides with the host is different from that of amines and may dominated by formation of hydrogen bonds between the amides protons and Cl ions of the host.
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Abrahamson, Michael J. "Development of an amine dehydrogenase." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/50138.
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Biocatalysts are increasingly prevalent in the large-scale synthesis of enantiomerically pure compounds. However, many sought-after reactions lack a suitable enzymatic production route. This work describes the development of a novel amine dehydrogenase through the application of directed evolution altering the substrate specificity of an existing leucine dehydrogenase scaffold. Eleven rounds of directed evolution completely altered the enzyme’s specificity and successfully created amination activity. The resulting amine dehydrogenase asymmetrically catalyzes methyl isobutyl ketone and free ammonia to 1, 3-dimethyl butyl amine. The enantioselectivity of the wild-type enzyme was maintained despite the drastic changes to the binding pocket and yielded (R)-1,3-DMBA with nearly complete conversion making it an attractive catalyst in the synthesis of chiral amines. This was the first example of a cofactor-dependent amine dehydrogenase capable of selectively synthesizing chiral amines from a prochiral ketone and free ammonia. Additionally, knowledge gained altering the specificity of the leucine dehydrogenase scaffold was applied to an analogous phenylalanine dehydrogenase scaffold allowing for rapid evolution of novel activity. A single mutational library resulted in a second amine dehydrogenase with enhanced activity toward significantly different substrates, while maintaining comparable conversion and enantioselectivity. These two scaffolds provide examples of the broad applicability of the identified mutations in creating amine dehydrogenase activity.
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Ghislieri, Diego. "Application of engineered amine oxidases for the synthesis of chiral amines." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/application-of-engineered-amine-oxidases-for-the-synthesis-of-chiral-amines(de93d851-97f8-4422-8dc4-0f7402488021).html.
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The development of cost-effective and sustainable catalytic methods for the production of enantiomerically pure chiral amines is a key challenge facing the pharmaceutical and fine chemical industries. There is an increasing demand for broadly applicable synthetic methods which deliver the desired amine product in high yield and enantiomeric excess (e.e.). Previously we have described the development of variants of monoamine oxidase from Aspergillus niger (MAO-N) which are able to mediate the complete conversion of racemic amines to the corresponding enantiomerically pure products in a single step. In this thesis we report a panel of MAO-N variants (D5, D9 and D11) developed in our laboratory, which are able to mediate the deracemisation of primary, secondary and tertiary amines with broad structural features. In particular, we have synthesized and subjected to deracemisation a broad range of tetrahydroisoquinolines and tetrahydro-β-carbolines checking enantioselectivity and enantiopreference of our biocatalysts. A relation between lipophilicity of the substituents and enantiopreference of the enzyme has been identified. We have also engineered a new MAO-N variant (D11) with a greatly increased substrate scope and enhanced tolerance for bulky substrates. Application of this engineered biocatalyst is highlighted by the asymmetric synthesis of the generic drugs Solifenacin and Levocetirizine as well as a number of important classes of biologically active alkaloid natural products. We also report a novel MAO-N mediated asymmetric oxidative Pictet-Spengler approach to the synthesis of (R)-harmicine.Another challenge facing the chemist in the new millennium is the development of cleaner and more efficient chemical processes. To this aim the combination of two or more catalytic systems to complete a series of cascade reactions is considered particularly appealing. We have reported a concurrent redox cascade for the deracemisation of pyrrolidines and tetrahydroisoquinolines using our monoamine oxidase-N with a biotinylated Ir-complex within streptavidin (SAV). To achieve the final goal it is necessary to shield the metal inside a host to avoid the mutual inactivation of the two catalysts. We have also described the combination of MAO-N with berberine bridge enzyme (BBE) for the synthesis of berbines (tetrahydroprotoberberines), which represent a sub-class of tetrahydro-isoquinoline alkaloids found in various plants. This bi-enzymatic cascade allows the synthesis of these structures achieving a theoretical 100% yield instead of the 50% given by the kinetic resolution using BBE itself.
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Rofouei, Mohammad Kazem. "The preparation, characterisation and reactivity of derivatives of a novel sterically demanding amido ligand." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361401.
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Johansen, Maren Teresa. "Degradation of Amines." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for kjemi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23201.
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In view of the rising amounts of greenhouse gases in the atmosphere, preventing CO2 emissions has become increasingly important. The combustion of fossil fuels for energy production and transportation is a large contributor to the problem. One of the ways to reduce the amounts of CO2 being released from combustion is carbon capture and storage (CCS). Post-combustion is the capturing method which has been deemed the easiest to apply to existing power plants in a short period of time. Absorption of CO2 by MEA is the most common method used in post-combustion carbon capture, but there are still many aspects of the process that are not fully understood. Understanding the absorption mechanisms will make it easier to make more economical and environmentally friendly choices in the future. In this thesis the oxidative degradation of monoethanolamine (MEA) has been studied using an open batch setup. The stability of MEA has been studied under different temperatures and concentrations of oxygen in the gas stream. These experiments give a matrix of experiments performed at 55, 65 and 75 °C, with oxygen concentrations of 6, 21, 50 and 98% in the gas stream. To monitor how well the experimental results could be trusted, the water balance was maintained throughout the experiments, and the pH was measured in the flasks capturing volatile degradation compounds.To get a detailed picture of the degradation, the weight percent of nitrogen and the CO2 concentration has been found in the end samples, and the alkalinity and MEA concentration was found for all the samples.11 known degradation compounds have been monitored for the different experiments, and the conditions these compounds are formed at have been compared with the suggested reaction mechanisms. 4 of the products were analyzed as anions using Ion chromatography (IC), and 7 secondary reaction products were analyzed as part of a degradation mix in LC-MS. The dependency of these compounds to temperature and oxygen conditions has been discussed. The primary degradation compounds seems to show a more direct correlation to oxygen flow or temperature, while the secondary degradation reaction shows a bigger variation of temperature and oxygen dependency relative to the conditions of the experiments. Various analytical methods for determination of the known compounds were used to determine the concentration of the degradation compounds in the experiments. The accuracy of these methods was investigated, and the results investigated for both LC-MS, GC-MS and IC-EC, showed large variations. Mixing experiments were performed to investigate the unknown mechanism of N-(2-hydroxyethyl) glycine.
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Heuson, Egon. "Recherche de nouvelles transaminases pour la synthèse d'amines chirales." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22659/document.
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Slatter, John Gregory. "Metabolism of tertiary arylaliphatic amines and formamides in rats." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/29392.
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The metabolites of the basic tertiary arylaliphatic amine N,N,α-trimethyl-7-phenylbenzenepropanamine (RecipavrinR) from male Wistar rats were characterized by gas chromatography-mass spectrometry (GCMS). The work was undertaken in an attempt to determine the source of a novel metabolite, N-(1-methyl-3,3-diphenylpropyl) formamide. The formamide metabolite was isolated from the bile of recipavrin dosed rats only after hydrolysis with the enzyme β-glucuronidase, suggesting that it arose from a glucuronide conjugated precursor. Recipavrin was chosen for the study based on structural similarity to the narcotic analgesic methadone which was shown to give rise to a similar metabolite, 6-formamido-4,4-diphenyl-3-heptanone.
The secondary formamide was not a plausible candidate for a β-glucuronidase liberated metabolite of recipavrin, suggesting that a labile aglycone was responsible for the GCMS observation of the formamide metabolite. Labile isomeric compounds, α-methyl-(N-methylene)-7-phenylbenzenepropanamine N-oxide, N-(α-methyl-7-phenylbenzenpropylidene) methylamine N-oxide, and 2-(4',4'-diphenyl-but-2'-yl) oxaziridine were synthesized as possible precursors of the formamide. N-hydroxy-a-methyl-7-phenylbenzenepropanamine, and N-hydroxy-N,α-dimethyl-7-phenylbenzenepropanamine were synthesized as candidates for labile β-glucuronidase liberated aglycone precursors of the nitrones.
The biliary nonconjugated and conjugated metabolites of recipavrin were characterized in detail. In addition to the formamide, 15 different metabolites representing the N- dealkylation, oxidative deamination, N-oxidation and phenyl ring oxidation pathways were identified by GCMS. To determine if thermal decomposition of the methylene nitrone in the GC inlet was responsible for the GCMS observation of the formamide metabolite, liquid chromatography-mass spectrometry (LCMS) was used to show that the formamide and not the isomeric methylene nitrone was present in bile prior to GCMS analysis. Although the synthetic methylene nitrone was shown to degrade in the GC inlet to the formamide, the LCMS experiment ruled out the thermal generation of the biliary formamide from a nitrone precursor.
The nonconjugated and conjugated metabolites of the recipavrin metabolite, norrecipavrin were characterized in detail by GCMS. Since the secondary formamide metabolite was observed in the β-glucuronidase hydrolyzed bile extract, norrecipavrin was implicated as an intermediate in the biotransformation of recipavrin to the formamide.
The possibility of solvent mediated formylation or free radical oxidation of desalkyl metabolites to afford the formamides was ruled out.
The methylene nitrone was shown to afford the formamide metabolite under simulated workup conditions. An alkali catalyzed Beckmann rearrangement of nitrone to amide was used to account for this transformation.
The secondary hydroxylamine was shown to give rise to the methylene nitrone under simulated workup conditions.
It was concluded that the oxidation of a β-glucuronidase liberated secondary hydroxylamine metabolite to the methylene nitrone followed by Beckmann rearrangement of the nitrone to the formamide was the probable source of the formamide observed by GCMS in extracts of bile from recipavrin dosed rats.
The metabolism of N-methyl-N-(1-methyl-3,3-
diphenylpropyl) formamide was investigated in detail to determine whether the carbinolamide, N-hydroxymethyl-N-(1-methyl-3,3-diphenylpropyl) formamide was involved in the genesis of the formamide metabolite of recipavrin. The above carbinolamide and N-(1-hydroxy-1-methyl-3,3-diphenylpropyl) formamide were identified by GCMS along with 16 other metabolites representing the metabolic pathways N-deformylation, N-dealkylation, N-oxidation and phenyl ring oxidation. The carbinolamides were not found in bile from recipavrin dosed rats, ruling out the possibility of a carbinolamide glucuronide precursor of the recipavrin formamide metabolite. This was the first report of the isolation of stable dealkylation intermediates of a high molecular weight formamide. The hepatotoxicity of the anticancer agent N-methyl formamide and the solvent dimethylformamide, suggests that the recipavrin formamides could also be metabolized to toxic carbinolamide or glutathione related metabolites.Pharmaceutical Sciences, Faculty of
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Li, Haiying. "A study on grafting poly(p-phenylene terephthalamide) with aliphatic amines and amides." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/8594.
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Lizier, Thiago Mescoloto [UNESP]. "Análise de aminas aromáticas em amostras de interesse ambiental por cromatografia líquida de alta eficiência acoplada a detectores de arranjo de diodo, eletroquímico e espectrometria de massas: Thiago Mescoloto Lizier. -." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/110706.
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000775008.pdf: 2574132 bytes, checksum: 055efec6156da665a55258df247b05c5 (MD5)O presente trabalho investiga novos métodos analíticos para análise de aminas aromáticas selecionadas em virtude de suas proprideades toxicológicas e/ou mutagênicas em amostras de interesse ambiental usando técnicas cromatográficas com diversos detectores. Após otimização das condições cromatográficas as aminas aromáticas: 4,4'-oxidianilina, anilina, 2,4- diaminotoluidina, 4,4'-diaminobifenila, 4,4'-metileno-bis-(2-cloroanilina), 3,3'-diclorobenzidina, 2- aminonaftaleno, 2-metilanilina, 2-metoxianilina, 4,4'-diaminodifenilmetano, 2-cloro-4-nitroanilina, 4-aminobifenila, 2-metoxi-5-metilanilina, 3,3'-dimetoxibenzidina, 4-cloroanilina e 3,3'- diclorobenzidina apresentaram picos bem DEfinidos em fase móvel metanol/água 70:30 (v/v) e vazão de 0,8 ml min-1 classificadas como grupo I. As aminas 1,4-diaminobenzeno, 4,4'- metilbenzeno-1,4-diamina, p-aminofenol, N-monoacetil-1,4-diaminobenzeno, 2,5-dimetilanilina, 4,4'-metileno-bis-2-metilanilina e 4-cloro-2-metilanilina foram agrupadas no grupo II, melhor separadas em fase móvel acetonitrila/água 60:40 (v/v), vazão 0,8 ml min-1 e T= 40 C. A comparação entre os detectores de arranjo de diodos (DAD) e eletroquímico (ED) foram conduzidos nestas condições otimizadas e curvas analíticas lineares foram construídas para todas estas aminas entre 1 a 250 mg L-1 (detector DAD = 230 nm) e 0,5 a 250 mg L-1 (detector ED - Ep = +1,0V)), utilizando para isto a adição de 30 x 10-3 Mol L-1 do líquido iônico BMIm-NTf2 (1-butil-3-metilimidazólio de bis(trifluorometilsulfonil)imida). A adição do líquido iônico promoveu melhor separação e aumento na intensidade dos picos cromatográficos em ambos os detectores. O limite de detecção das aminas por HPLC-DAD e HPLC-ED mostraram valores entre 1,27 a 10,2 mg L-1 e 1,33 a 6,04 mg L-1, respectivamente. O limite de quantificação das aminas por HPLC-DAD e HPLC-ED mostraram valores entre 4,24 a 34,0 mg L-1 e 4,44 a 20,1 mg L-1, ...
This work investigates new analytical methods for analysis of aromatic amines selected because of their toxicological and/or mutagenic properties in samples of environmental interest using chromatographic techniques with various detectors. After optimization of chromatographic conditions as aromatic amines: 4,4'-oxydianiline, aniline, 2,4-diaminotoluidina, 4,4'- diaminobifenila, 4,4'-methylenebis-(2-chloroaniline), 3,3'-dichlorobenzidine, 2- aminonaphthalene, 2-methylaniline, 2-methoxyaniline, 4,4'-diaminodiphenylmethame, 2-chloro- 4-nitroaniline, 4-aminobifenila, 2-methoxy-5-methylaniline, 3,3'-dimethoxybenzidine, 4- chloroaniline and 3,3'-dichlorobenzidine showed well defined peaks in the mobile phase methanol/water 70:30 (v/v) and a flow rate of 0.8 mL min-1 classified as group I. The amines 1,4- diaminobenzene, 4,4'-methylbenzene-1,4-diamine, p-aminophenol, N-monoacethyl-1,4- diaminobenzene, 2,5-dimethylaniline, 4,4'-methylene-bis-2-methylaniline and 4-chloro-2- methylaniline were grouped in group II, best separated in the mobile phase acetonitrile/water 60:40 (v/v), flow rate 0.8 mL min-1 and T = 40°C. The comparison between the diode array detector (DAD) and electrochemical (ED) were conducted on these optimized conditions, linear calibration curves were constructed for all these amines from 1 to 250 mg L-1 (DAD detector = 230 nm) and 0.5 to 250 mg L-1 (detector ED - Ep = +1.0 V), using for this purpose the addition of 30 x 10-3 mol L-1 of BMIm-NTf2 ionic liquid (1-butyl-3-methylimidazolium-bis- (trifluoromethylsulfonyl)imide). The addition of ionic liquid promoted better separation and increase in the intensity of the chromatographic peaks in both detectors. The HPLC-DAD and HPLC-ED detection limit of the amines showed values between 1.27 to 10.2 mg L-1 and 1.33 to 6.04 mg L-1, respectively. The HPLC-DAD and HPLC-ED limit of quantification of the amines showed values between 4.24 to 34.0 mg L-1 and from 4.44 to 20.1 mg L-1,...
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Machado, Margarete Oliveira. "Fosfato de bario, intercalação e termoquimica." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250040.
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Orientador: Claudio AiroldiDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Mestrado
Quimica Inorganica
Mestre em Química
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Lizier, Thiago Mescoloto. "Análise de aminas aromáticas em amostras de interesse ambiental por cromatografia líquida de alta eficiência acoplada a detectores de arranjo de diodo, eletroquímico e espectrometria de massas / Thiago Mescoloto Lizier. -." Araraquara, 2014. http://hdl.handle.net/11449/110706.
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Orientador: Maria Valnice Boldrin ZanoniBanca: Manoel Lima de Menezes
Banca: Sônia Maria Alves Jorge
Banca: Nivia Maria Melo Coelho
Banca: Teresa Cristina Rodrigues dos Santos Franco
Resumo: O presente trabalho investiga novos métodos analíticos para análise de aminas aromáticas selecionadas em virtude de suas proprideades toxicológicas e/ou mutagênicas em amostras de interesse ambiental usando técnicas cromatográficas com diversos detectores. Após otimização das condições cromatográficas as aminas aromáticas: 4,4'-oxidianilina, anilina, 2,4- diaminotoluidina, 4,4'-diaminobifenila, 4,4'-metileno-bis-(2-cloroanilina), 3,3'-diclorobenzidina, 2- aminonaftaleno, 2-metilanilina, 2-metoxianilina, 4,4'-diaminodifenilmetano, 2-cloro-4-nitroanilina, 4-aminobifenila, 2-metoxi-5-metilanilina, 3,3'-dimetoxibenzidina, 4-cloroanilina e 3,3'- diclorobenzidina apresentaram picos bem DEfinidos em fase móvel metanol/água 70:30 (v/v) e vazão de 0,8 ml min-1 classificadas como grupo I. As aminas 1,4-diaminobenzeno, 4,4'- metilbenzeno-1,4-diamina, p-aminofenol, N-monoacetil-1,4-diaminobenzeno, 2,5-dimetilanilina, 4,4'-metileno-bis-2-metilanilina e 4-cloro-2-metilanilina foram agrupadas no grupo II, melhor separadas em fase móvel acetonitrila/água 60:40 (v/v), vazão 0,8 ml min-1 e T= 40 C. A comparação entre os detectores de arranjo de diodos (DAD) e eletroquímico (ED) foram conduzidos nestas condições otimizadas e curvas analíticas lineares foram construídas para todas estas aminas entre 1 a 250 mg L-1 (detector DAD = 230 nm) e 0,5 a 250 mg L-1 (detector ED - Ep = +1,0V)), utilizando para isto a adição de 30 x 10-3 Mol L-1 do líquido iônico BMIm-NTf2 (1-butil-3-metilimidazólio de bis(trifluorometilsulfonil)imida). A adição do líquido iônico promoveu melhor separação e aumento na intensidade dos picos cromatográficos em ambos os detectores. O limite de detecção das aminas por HPLC-DAD e HPLC-ED mostraram valores entre 1,27 a 10,2 mg L-1 e 1,33 a 6,04 mg L-1, respectivamente. O limite de quantificação das aminas por HPLC-DAD e HPLC-ED mostraram valores entre 4,24 a 34,0 mg L-1 e 4,44 a 20,1 mg L-1, ...
Abstract: This work investigates new analytical methods for analysis of aromatic amines selected because of their toxicological and/or mutagenic properties in samples of environmental interest using chromatographic techniques with various detectors. After optimization of chromatographic conditions as aromatic amines: 4,4'-oxydianiline, aniline, 2,4-diaminotoluidina, 4,4'- diaminobifenila, 4,4'-methylenebis-(2-chloroaniline), 3,3'-dichlorobenzidine, 2- aminonaphthalene, 2-methylaniline, 2-methoxyaniline, 4,4'-diaminodiphenylmethame, 2-chloro- 4-nitroaniline, 4-aminobifenila, 2-methoxy-5-methylaniline, 3,3'-dimethoxybenzidine, 4- chloroaniline and 3,3'-dichlorobenzidine showed well defined peaks in the mobile phase methanol/water 70:30 (v/v) and a flow rate of 0.8 mL min-1 classified as group I. The amines 1,4- diaminobenzene, 4,4'-methylbenzene-1,4-diamine, p-aminophenol, N-monoacethyl-1,4- diaminobenzene, 2,5-dimethylaniline, 4,4'-methylene-bis-2-methylaniline and 4-chloro-2- methylaniline were grouped in group II, best separated in the mobile phase acetonitrile/water 60:40 (v/v), flow rate 0.8 mL min-1 and T = 40°C. The comparison between the diode array detector (DAD) and electrochemical (ED) were conducted on these optimized conditions, linear calibration curves were constructed for all these amines from 1 to 250 mg L-1 (DAD detector = 230 nm) and 0.5 to 250 mg L-1 (detector ED - Ep = +1.0 V), using for this purpose the addition of 30 x 10-3 mol L-1 of BMIm-NTf2 ionic liquid (1-butyl-3-methylimidazolium-bis- (trifluoromethylsulfonyl)imide). The addition of ionic liquid promoted better separation and increase in the intensity of the chromatographic peaks in both detectors. The HPLC-DAD and HPLC-ED detection limit of the amines showed values between 1.27 to 10.2 mg L-1 and 1.33 to 6.04 mg L-1, respectively. The HPLC-DAD and HPLC-ED limit of quantification of the amines showed values between 4.24 to 34.0 mg L-1 and from 4.44 to 20.1 mg L-1,...
Doutor
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Marczylo, Timothy Hywel. "Bioactivation of aromatic amines." Thesis, University of Surrey, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336523.
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Bourne, I. A. "Medium-ring bicyclic amines." Thesis, University of Bristol, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375000.
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Nealon, Gareth L. "Substituted cage amines : towards new functional metalloassemblies." University of Western Australia. School of Biomedical and Chemical Sciences, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0215.
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FEREY, VINCENT. "Utilisation de complexes amine-borane dans la synthese stereoselective de derives d'acides alpha-amines." Paris 11, 1996. http://www.theses.fr/1996PA112084.
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Ce memoire concerne l'etude de nouvelles methodes stereoselectives d'acces a des derives d'acides alpha-amines, precurseurs d'acides alpha-amines non proteinogeniques. Dans la premiere partie, nous decrivons des tentatives d'utilisation d'heterocycles comportant une fonction amidine ou iminoester. Cependant, ces composes, utilises comme substrats dans des reactions d'alkylation pouvant nous mener aux derives desires, se sont reveles inertes vis-a-vis de bases fortes. Ainsi, malgre de nombreuses variantes synthetiques explorees, cette etude n'a pas donne les resultats escomptes. Une approche plus generale utilisant comme substrats des complexes amine-borane a ensuite ete mise au point. Nous presentons successivement: - dans la deuxieme partie, une revue bibliographique sur la synthese de ces complexes et leur utilisation en synthese organique. - dans la troisieme partie, une etude de l'influence de la complexation par le borane d'un aminoester sur sa reactivite dans la reaction d'aldolisation: elle nous permet, suivant les conditions, de preparer selectivement des alpha-amino-beta-hydroxyesters de configuration syn ou anti. - dans la quatrieme partie, une methode enantioselective d'acces a des acides alpha-amines alpha-substitues, derives de l'alanine et de la proline. Cette methode repose sur une preparation efficace et diastereoselective de complexes amine-borane chiraux, et sur une procedure d'alkylation conduisant a des composes enantiomeriquement enrichis (purete enantiomerique: jusqu'a 92%)
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Despeyroux, Pierre. "Réactivité des amines et des dérivés organométalliques en série 3-déshydroquinique : Modélisation d'activités 3-déshydroquinate hydrolyase." Toulouse 3, 1990. http://www.theses.fr/1990TOU30048.
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Ce travail a pour objectif la comprehension et a terme le controle du mode d'action d'enzymes de la voie de l'acide shikimique. Cette voie de biosynthese est specifique des microorganismes et des vegetaux, elle conduit aux acides amines aromatiques ainsi qu'a d'autres metabolites essentiels. Nous nous sommes interesses a la modelisation du mecanisme enzymatique de la 3-deshydroquinate hydrolyase (dhqase) et a la reactivite de son substrat: l'acide 3-deshydroquinique. Le premier chapitre constitue une mise au point bibliographique des resultats recents de la voie de l'acide shikimique. Le deuxieme chapitre concerne la modelisation par voie chimique du mecanisme de la 3-deshydroquinate hydrolyase, qui fait intervenir dans une premiere etape la formation d'une base de schiff. Le troisieme chapitre concerne la synthese de composes analogues du premier intermediaire reactionnel gem-aminoalcool intervenant dans le processus catalytique de la dhqase. Ces composes sont obtenus apres attaque nucleophile par differents reactifs organometalliques sur la fonction carbonyle du 3-deshydroquinate de methyle trisilyle. La determination des structures de ces derives et les essais d'assignation de la configuration de carbone asymetrique cree sont rapportes dans le quatrieme chapitre. La stereoselectivite des additions est discutee dans le dernier chapitre
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Branquet, Éric. "Synthese d'amino sucres et d'acides alpha-amines exotiques a partir d'acides alpha-amines naturels." Paris 6, 1993. http://www.theses.fr/1993PA066521.
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Le pool chiral que represente les acides alpha-amines en synthese organique a fait l'objet de nombreuses applications dans la synthese d'acides amines non usuels, mais peu d'applications dans la synthese des amino sucres ont ete decrites. Sont decrites dans ce rapport: a) une nouvelle approche de synthese de trois-amino-trois-desoxy tetro ou pentofuranosides diversement substitues en position deux et de trois-amino-trois-desoxy, thiofuranosides, a partir de beta-hydroxy ou de beta-thio amino acides naturels. Ces sucres sont des analogues de la partie glycosidique de molecules naturelles tels que les antibiotiques nucleosidiques, les macrolides, les anthracyclines. Une extension a la synthese de quatre-amino-quatre-desoxy hexoses a aussi ete etudiee; b) la synthese enantioselective de l'ethynyl glycine en utilisant un equivalent de l'acide penaldique: le n-terbutyloxycarbonyl serinal acetonide. Parallelement, cette voie de synthese a permis d'acceder a de nouveaux deux-amino-un, trois-dienes diversement substitues en position quatre selon un rearrangement de type klemer-rodemeyer a partir de un, trois-(n, o)-oxazolidines; c) la synthese d'un dipeptide l-phe/acide alpha-amine-beta-gamma-ether d'enol par une isomerisation de type schollkopf
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ROUSSELET, GUILHEM. "Nouvelles reactions cupro-catalysees des amines. Transformation des amines tertiaires et des n-oxydes en ions iminiums, epoxydation intramoleculaire. Synthese et utilisation synthetique des amidines." Paris 6, 1996. http://www.theses.fr/1996PA066368.
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Les sels cuivriques ainsi que l'oxygene moleculaire en presence de sels cuivreux oxydent la trimethylamine en ion n,n-dimethyliminium. Ce resultat conduit a la description d'un modele biomimetique de l'oxydation des amines tertiaires par les cupro-enzymes laccase et ceruloplasmine humaine. L'etude de la transformation des n-oxydes d'amines par les sels de cuivre a permis la mise au point d'une nouvelle voie d'acces aux ions iminiums. L'oxydation des 1-methyltetrahydropyridines resultant de l'interaction de l'oxygene moleculaire sur les sels cuivreux, et la transformation de leurs n-oxydes par les sels de cuivre conduisent a la formation d'epoxydes. Une meme espece active du cuivre, formellement de degre d'oxydation 3, est responsable de ces deux reactions. Les sels cuivreux catalysent la formation des amidines par condensation directe des amines sur les nitriles. La mesure de la constante de complexation des sels cuivreux par les amidines a permis de rationaliser le role du cuivre dans cette premiere synthese generale des amidines en une etape. Nous presentons de nouvelles reactions qui valorisent les amidines comme intermediaires de synthese, en particulier par reduction (synthese d'amines tertiaires par n-alkylation reductrice des nitriles) et par oxydation (heterocycles polyazotes, derives fonctionnalises 1,2)
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Said, Sadri A. "Stereoselective Transformations of Chiral Amines." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, 2002. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-97.
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Enantiomerically pure amines and alcohols are particularly important synthons for the preparation of pharmaceuticals and agrochemicals. Notwithstanding the advances that have been achieved in asymmetric synthesis, resolution of racemates is probably the most current approach for the preparation of pure enantiomers. On the other hand, resolution processes suffer from disadvantages of low yields caused by the loss of at least 50% of the undesired isomer. Among the attractive methods for avoiding the drawbacks of resolution processes is inversion of configuration of the unwanted isomer. Although there are several existing methodologies for inversion and stereoselective transformations of chiral alcohols, corresponding methods for inversion of chiral amines has received less attention. The main objective of the project “Stereoselective transformations of chiral amines” was therefore to develop effective methods for inversion and stereoselective transformations of chiral amines.
This thesis discuss the utility of three nucleophilic substitution methods in stereoselective transformations of chiral amines.
The first investigation towards this goal was carried out using cyclic aryldisulfonylimide leaving group. Substitution of a chiral amine via N,Nnaphthalene- 1,2-disulfonylimide intermediate gave azide and alcohol products with 60-73% inversion of configuration, which was 20-25% lower compared to the previously studied relative disulfonylimides. Displacement of this group using aroxide anions afforded chiral aryl ethers with 70-87% inversion of stereochemistry. Chiral analysis of the ether products required synthesis of authentic reference compounds. This was achieved via benzyne route and by nucleophilic substitution on the derivatives of chiral alcohols. The benzyne route gave chiral phenyl ether from enantiopure alcohols with complete retention of configuration while the trifluoroacetate derivatives of chiral alcohols produced chiral aryl ethers with complete inversion of stereochemistry.
The 2,4,6-triphenylpyridinium cations were the next intermediates investigated in this study. These derivatives were synthesized from 2,4,6-triphenylpyrylium tetrafluoroborate in 84-90% yields using procedures described by Katritzky. Nucleophilic substitution on pyridinium salts of aliphatic chiral amines using azide and hydroxide anions gave products with 96 to 100% inversion of configuration.
The utility of diazonium salts for inversion of chiral amines was also investigated in the present study. This method was only focused on stereoselective transformations of α-amino acids as diazotization-dediazoniation of other aliphatic amines is of little interest for organic synthesis. Diazotization of L-alanine and L-phenylalanine ethyl esters hydrochlorides using alkyl nitrites in aprotic solvents, in the presence of azide anion, yielded optically active chloro substituents as the only products, instead of the intended azide compounds. Attempts to avoid counterion substitution by using ammonium tosylate to replace the ammonium chlorides was not useful and a tosyl product was isolated instead. Proposals to rectify this problem have been suggested. These include the use of much more inert counterions such as tetrafluoroborate or replacing the hydrochlorides with hydroazides. An alternative which could deliver the nucleophile in an intramolecular fashion has also been postulated. Investigations of these hypotheses are currently conducted.
Parallel to diazotization reactions was an investigation on inversion of α-amino acids via N,N-disulfonylimides and 2,4,6-triphenylpyridinium cation leaving groups. Studies with N,N-disulfonylimide derivatives showed that this leaving group is not useful for inversion of α-amino acids. Nucleophilic substitution on the 2,4,6-triphenylpyridinium salts of amino acids afforded partial racemized substitution products. The drawback in the utility of the pyridinium salts has been identified and efforts are underway to remove this impediment.
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Walsh, Kelly Ann. "The alkylation of aromatic amines." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7659.
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N-alkylated anilines can be obtained in moderate yields from aniline and methyl formate in the presence of Rh$\sb6$(CO)$\sb $ and KI after 72 hours at 180-200$\sp\circ$C. Ru$\sb3$(CO)$\sb $ gave similar results to the unpromoted rhodium carbonyl system. Formanilide and N-methylformanilide were also formed in the reaction. The (HCr(CO)$\sb5$) -anion in the form of its PPN$\sp+$ and Et$\sb4$N$\sp+$ salts also catalysed this reaction (under hydrogen) but was selective to the formanilide products. The presence of an electron donating group on the aromatic ring favoured the formation of alkylated products in the presence of bis(triphenylphosphine)iminium (PPN$\sp+$) hydridochromiumpenta-carbonyl. Several possible mechanisms were tested and the nature of the polynuclear catalysts investigated.
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Smethurst, Chris. "Asymmetric synthesis of cyclic amines." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298718.
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Harrison, Michael John. "Asymmetric synthesis using chiral amines." Thesis, University of York, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280371.
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Houlsby, Ian. "Asymmetric syntheses of polycyclic amines." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:7c73384d-da09-41ee-b1fc-4509dd20aaf8.
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This thesis centers on the asymmetric synthesis of polycyclic amines, focussing on three distinct classes of polycyclic alkaloid natural products. The work aims to use common methodology of lithium amide conjugate additions as the source of asymmetry in all cases, and for each product class a single strategy is used to synthesise a variety compounds. Chapter 1 describes the importance of the synthesis of polycyclic alkaloids, highlighting three classes of compounds and documenting prior synthetic strategies. The classes discussed are: the Hancock alkaloids, hydroxymethyl-substituted azabicycles, and the tetraponerine alkaloids. Chapter 2 describes two separate synthetic strategies towards the Hancock alkaloid (-)-cuspareine, one using a benzyne mediated cyclisation and one a Buchwald-Hartwig cyclisation. The Buchwald-Hartwig methodology was also applied in the synthesis of two more Hancock alkaloids (-)-galipinine and (-)-galipeine; the synthesis of (-)-galipeine led to a reassignment of the structure of the natural product. Chapter 3 describes work in the synthesis of four [x.y.0]-azabicycles with differing in ring sizes (x, y = 3, 4). The strategy employs sequential SN2-like ring-closing reactions to form the bicyclic structures where pyrrolizidine, indolizidine and quinolizidine scaffolds can be accessed. Amongst the products are two natural alkaloids, (-)-lupinine and (+)-isoretronecanol. Chapter 4 describes the synthesis of all eight tetraponerine alkaloids T1-8. Two sequential lithium amide conjugate addition reactions allow for the synthesis of the differing ring-sizes and diastereoisomers displayed by the eight alkaloids. Ring-closing metathesis and diamine condensation with 4-bromobutanal provide the ring-closing steps in the syntheses. Chapter 5 contains full experimental procedures and characterisation data for all compounds synthesised in Chapters 2-4.
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CHAROY, LAURENT. "Acides amines et peptides bores." Paris 6, 1995. http://www.theses.fr/1995PA066049.
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La synthese d'analogues d'acides amines dont le carbone alpha est remplace par un bore a ete etudiee. Les proprietes de ces analogues ouvrent un large domaine d'applications biologiques et medicales (i. R. M. , b. N. C. T. , inhibition enzymatique), en particulier en tant qu'inhibiteurs potentiels de la biosynthese du pentapeptide du peptidoglycane. Dans un premier temps, la synthese des analogues de la glycine, de l'alanine et de la phenylalanine sous forme d'acide carboxylique a ete envisagee, a partir des derives nitriles correspondants. Les intermediaires amides, imidates et parfois esters ont ete obtenus, mais seule la glycine a pu etre hydrolysee en acide. Aucun test biochimique n'a ete effectue a l'heure actuelle. En revanche, cette etude a permis de mettre en evidence la chiralite du bore dans ces composes, et de separer et de caracteriser les enantiomeres des derives nitriles de l'analogue de la phenylalanine. Dans un deuxieme temps, la synthese directe de dipeptides contenant un analogue bore en position n-terminale a ete etudiee. Celle-ci a pu etre realisee a partir des derives nitriles des analogues bores, par alkylation grace a un ester triflique judicieusement choisi, suivie d'une hydrolyse. Cette methode simple et originale permet de s'affranchir du passage par l'acide carboxylique. Enfin, l'etude par rmn du pseudo-dipeptide borophe-ala a permis d'attribuer les configurations relatives du bore et du carbone asymetrique du residu c-terminal
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PONSINET, RACHEL. "Synthese diastereoselective d'acides beta-amines." Paris 6, 1999. http://www.theses.fr/1999PA066411.
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Si de nombreuses publications decrivent la synthese enantioselective d'acides -amines substitues en de la fonction acide (acides 3-amines) ou disubstitues en et , peu en revanche, concernent la synthese d'acides -amines uniquement substitues en (acides 2-amines). La plus grande partie du travail decrit dans cette these est axee sur une nouvelle voie de synthese diastereoselective d'acides 2-amines. Pour cela, deux strategies ont ete etudiees : la premiere correspond a une carboxylation enantioselective en d'une fonction nitrile (precurseur de la fonction amine). Elle est basee sur l'utilisation d'un electrophile chiral, obtenu par action du triphosgene sur le sultame d'oppolzer, et a conduit a la 2-phenylglycine enantiomeriquement pure. Mais elle n'est pas applicable a la synthese d'autres acides 2-amines a chaines laterales carbonees. La deuxieme strategie est basee sur l'alkylation d'un precurseur chiral derive de la -alanine. L'introduction de la chaine laterale de l'acide amine souhaite se fait avec une stereochimie induite par l'auxiliaire chiral : le sultame d'oppolzer. Cette strategie a permis d'obtenir la 2-phenylalanine, la 2-alanine et la 2-leucine avec d'excellents exces enantiomeriques. Elle necessite l'utilisation d'agents alkylants reactifs a basse temperature pour eviter l'elimination de l'enolate. Des etudes preliminaires portant sur l'introduction de chaines laterales fonctionnalisees (telles que celles de la lysine, de la methionine ou de l'acide aspartique) ont ete engagees, elles seront poursuivies. Les acides 2-amines aromatiques obtenus suivant ces deux strategies ont ete introduits dans la sequence de la substance p. Ces premiers analogues se sont averes etre peu affins et peu actifs. Une autre partie de ce travail a porte sur la mise au point d'une voie de synthese d'acides 3-amines (en particulier la 3-alanine) a partir de l'acide aspartique, en vue d'une application a grande echelle.
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Jie, Yuanping Livant Peter D. "Tris(1,3-dihydroxy-2-propyl)amine, a planar trialkylamine synthesis, structure, and properties ; a potential precursor to hypervalent nitrogen /." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Spring/doctoral/JIE_YUANPING_0.pdf.
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Cooper, Cindy L. "Neuropeptides, amines and amine receptors in the human spinal cord : the effects of Parkinson's disease." Thesis, University of Nottingham, 1989. http://eprints.nottingham.ac.uk/13218/.
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The aims of this study were to investigate (i) the levels of catecholamines, indoleamines, substance P and thyrotrophin-releasing hormone (TRH) in the post-mortem spinal cord of subjects who had died with Parkinson's disease and to compare them with those of control subjects (ii) adrenergic and serotonergic receptors in the post-mortem Parkinsonian and control spinal cord and (iii) the effects of subject age and sex and the interval between death and post-mortem (PMI) on the levels of neurotransmitters and neuropeptides and on receptor binding in post-mortem tissue. To perform these investigations (i) a sensitive radioimmunoassay which is specific for substance P and has low cross-reactivity with other similar peptides and (ii) a common extraction medium for the concomitant extraction of catecholamines, indoleamines, substance P and TRH from CNS tissue were developed. The main findings were: There were significant correlations between the levels of 5HT, TRH and α2-adrenoceptor binding and both subject age and the PMI. In Parkinson's disease compared with control subjects: (i) the levels of noradrenaline were significantly reduced in the thoracic ventral region of the spinal cord,(ii) dopamine levels were higher in the thoracic ventral and dorsal spinal cord,(iii) in the lumbar spinal cord 5HT levels were significantly reduced in the dorsal horn with an increase in the ratio of 5HIAA/5HT, (iv) noradrenaline levels were reduced in both dorsal and ventral horns of the lumbar spinal cord and (v) there were no differences between the levels of substance P and TRH in any spinal cord region. There were no measurable 5HT1A or 5HT2 binding sites in the human spinal cord under the conditions used. However, specific α2-adrenoceptor binding was defined in terms of binding affinity and number of receptors in the spinal cord.
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Wang, Xuan. "Studies on preparation of aromatic amines and their synthetic and biological applications /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202005%20WANG.
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Oliveira, Margarete 1955. "O biopolímero quitosana, modificado quimicamente ou reticulado com metais, em forma de pó ou esfera, aplicado no estudo termiquímico da interação com cobre e aminas alifáticas." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250070.
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Orientador: Claudio AiroldiTese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
Made available in DSpace on 2018-08-20T16:49:01Z (GMT). No. of bitstreams: 1 Oliveira_Margarete_D.pdf: 1553747 bytes, checksum: be6468e728bf6f82ae6cb1e127a8f600 (MD5) Previous issue date: 2011
Resumo: O biopolímero quitosana foi sintetizado através da desacetilação alcalina do polissacarídeo precursor quitina, mediante reação com hidróxido de sódio e o seu grau de desacetilação foi determinado a partir da espectroscopia de absorção na região do infravermelho. A quitosana foi quimicamente modificada através de reações com acetilacetona, epicloridrina e glutaraldeído, explorando-se a reatividade dos grupos hidroxila e amino livres da estrutura polimérica original. Os derivados na forma de pó foram usados como sorventes para o cátion cobre em solução aquosa. Esferas de quitosana reticulada com Cu foram obtidas através de uma única etapa de reação, o que foi possível devido à grande habilidade do biopolímero em se coordenar ao cátion, através da disponibilidade da função amina na estrutura polimérica. Por adaptação dessa nova metodologia foram obtidas também esferas com Ni e Co. Os novos biopolímeros sintetizados contendo cobre e níquel atuaram com sucesso na remoção de monoaminas de soluções aquosas. Os dados termodinâmicos calculados a partir da titulação calorimétrica mostram que, na sorção do cátion cobre com quitosanas quimicamente modificadas ou de aminas com esferas reticuladas, os efeitos interativos são favoráveis e espontâneos, refletindo em entalpias exotérmicas e valores negativos de energias de Gibbs. Os valores positivos das entropias refletem um aumento de espécies livres em solução, após o efeito interativo, decorrentes da liberação de moléculas do solvente, com dessolvatação tanto do biopolímero, como do cátion ou das moléculas de aminas ligadas ao solvente
Abstract: The biopolymer chitosan was synthesized by alkaline deacetylation of the precursor polysaccharide chitin by reaction with sodium hydroxide, which degree of deacetilation was determined from absorption spectroscopy in the infrared region. Chitosan were chemically modified by reactions with acetylacetone, glutaraldehyde and epichlorohydrin, exploring the reactivity of hydroxyl and amino free pendant groups linked to original polymeric structure. The derivatives in powder form were used as sorbents for copper cation in aqueous solution. Beads of chitosan crosslinked with Cu were obtained from one step reaction, due to the fact that the biopolymer has high ability in cation coordination, through the availability of the amine functions in the polymeric structure. Based on this methodology other spheres containing Ni and Co were also synthesized. The new biopolymers crosslinked with copper and nickel act with success in monoamine removal from aqueous solution. Thermodynamic data calculated from calorimetric titration show that the copper cation sorption on chitosan chemically modified or amines with crosslinked beads at the solid/liquid interface, gave exothermic enthalpies and negative Gibbs energy values, demonstrating that the interactive effects are thermodynamically favorable and spontaneous. The entropic positive values reflect an increase in free species in solution, after interactive effect due to the solvent molecules released, with biopolymer desolvation, as well as, from cation in solution or solvent molecules bonded to aliphatic amines
Doutorado
Quimica Inorganica
Doutor em Ciências
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Alcover, Fortuny Natàlia. "Asymmetric synthesis of chiral amines using transaminases: a multienzymatic approach by pyruvate decarboxylase coupling." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/671815.
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La present tesi es centra en el desenvolupament i optimització d’una estratègia basada en la biocatàlisi per a la síntesi d’amines quirals, les quals són compostos òpticament actius de gran valor que poden ésser utilitzats per a la síntesi de nombrosos productes, especialment en les indústries farmacèutica i agroquímica. Més concretament, es pretén sintetitzar 3-amino-1-fenilbutà (3-APB) i 1-feniletilamina (1-PEA) a través de la reacció en cascada de la transaminasa (TA) i la piruvat decarboxilasa (PDC). Aquesta cascada es basa en una síntesi asimètrica que parteix de les seves corresponents cetones proquirals i l’alanina, i és catalitzada per omega-transaminases, les quals presenten un equilibri desfavorable. Per tal de solucionar aquest problema, la PDC actua com un sistema d’eliminació de producte secundari, a través de la transformació del piruvat a acetaldehid i CO2, la qual cosa provoca un desplaçament de l’equilibri. Amb l’objectiu de superar les limitacions comercials de la PDC, la qual només es pot obtenir en petites quantitats a un cost alt, es va desenvolupar un procés sencer de producció d’aquest enzim. Es va clonar i sobreexpressar el gen de la PDC de Zymobacter palmae (ZpPDC) en Escherichia coli. Posteriorment, es va obtenir l’enzim recombinant en grans quantitats a través del desenvolupament d’un procés de cultiu d’alta densitat cel·lular en bioreactor. Pel que fa a les TAs, es disposava de quatre enzims diferents, procedents de Chromobacterium violaceum (Cvi-TA), Vibrio fluvialis (Vfl-TA) i Aspergillus terreus (Ate-TA i Ate-TA_T247S). Es va caracteritzar tant la PDC com les quatre transaminases per tal de trobar les condicions de compromís adequades per a la construcció de la cascada enzimàtica. Tenint en compte les condicions trobades, es va dur a terme, de forma preliminar, reaccions de cribratge de les quals en van sortir seleccionades la Cvi-TA i la Vfl-TA per a la síntesi de 3-APB; i Vfl-TA per a la síntesi de 1-PEA. Després de demostrar la viabilitat de la reacció en cascada de la TA i la PDC, es van aplicar diferents estratègies d’optimització per tal de maximitzar els rendiments de reacció i millorar la baixa estabilitat operacional de les transaminases. Per una banda, es van explorar algunes estratègies d’optimització de les condicions de reacció. Per l’altra, es va aplicar enginyeria del medi de reacció. Posteriorment, es va dur a terme d’immobilització dels enzims. Es van obtenir derivats immobilitzats tant de la Cvi-TA com de la Vfl-TA en suports de MANA-agarosa i epoxy-agarosa. En el cas de la PDC, es va desenvolupar un sistema innovador de purificació i immobilització simultània en MANA-agarosa. Finalment, els enzims immobilitzats obtinguts van ser aplicats en reacció i es va desenvolupar una estratègia de reacció en cicles.La presente tesis se centra en el desarrollo y optimización de una estrategia basada en la biocatálisis para la síntesis de aminas quirales, las cuales son compuestos ópticamente activos de gran valor que pueden ser utilizados para la síntesis de numerosos productos, especialmente en las industrias farmacéutica y agroquímica. Más concretamente, se pretende sintetizar 3-amino-1-fenilbutano (3-APB) y 1-feniletilamina (1-PEA) a través de la reacción en cascada de la transaminasa (TA) y la piruvato decarboxilasa (PDC). Esta cascada se basa en una síntesis asimétrica que parte de sus correspondientes cetonas proquirales y la alanina, y es catalizada por omega-transaminasas, las que presentan un equilibrio desfavorable. Para solucionar este problema, la PDC actúa como un sistema de eliminación de producto secundario, a través de la transformación del piruvato en acetaldehído y CO2, lo que provoca un desplazamiento del equilibrio. Con el objetivo de superar las limitaciones comerciales de la PDC, la cual sólo se puede obtener en pequeñas cantidades a un coste alto, se desarrolló un proceso entero de producción de esta enzima. Se clonó y sobreexpresó el gen de la PDC de Zymobacter Palmae (ZpPDC) en Escherichia coli. Posteriormente, se obtuvo la enzima recombinante en grandes cantidades a través del desarrollo de un proceso de cultivo de alta densidad celular en bioreactor. En cuanto a las TAs, se disponía de cuatro enzimas diferentes, procedentes de Chromobacterium violaceum (Cvi-TA), Vibrio fluvial (Vfl-TA) y Aspergillus Terreus (Ate-TA y Ate-TA_T247S). Se caracterizó tanto la PDC como las cuatro transaminasas con el fin de encontrar las condiciones de compromiso adecuadas para la construcción de la cascada enzimática. Teniendo en cuenta las condiciones encontradas, se llevó a cabo, de forma preliminar, reacciones de cribado de las que salieron seleccionadas la Cvi-TA y la Vfl-TA para la síntesis de 3-APB; y Vfl-TA para la síntesis de 1-PEA. Tras demostrar la viabilidad de la reacción en cascada de la TA y la PDC, se aplicaron diferentes estrategias de optimización para maximizar los rendimientos de reacción y mejorar la baja estabilidad operacional de las transaminasas. Por un lado, se exploraron algunas estrategias de optimización de las condiciones de reacción. Por el otro, se aplicó ingeniería del medio de reacción. Posteriormente, se llevó a cabo de inmovilización de las enzimas. Se obtuvieron derivados inmovilizados tanto de la Cvi-TA como de la Vfl-TA en soportes de MANA-agarosa y epoxy-agarosa. En el caso de la PDC, se desarrolló un sistema innovador de purificación e inmovilización simultánea en MANA-agarosa. Finalmente, las enzimas inmovilizadas obtenidas fueron aplicadas en reacción y se desarrolló una estrategia de reacción en ciclos.
The present thesis is focused on the development and optimization of a biocatalytical approach for the synthesis of chiral amines, which are highly valuable optically active compounds that can be used for the synthesis of numerous targets, especially in pharmaceutical and agrochemical industry. More specifically, 3-amino-1-phenylbutane (3-APB) and 1-phenylethylamine (1-PEA) synthesis is pretended by the cascade reaction of transaminase (TA) and pyruvate decarboxylase (PDC). The mentioned cascade consists in an asymmetric synthesis from their corresponding prochiral ketones and alanine catalyzed by omega-transaminase, which presents an unfavorable equilibrium. To overcome this problem, PDC acts as a by product removing system by transforming the resulting pyruvate to acetaldehyde and CO2, which leads to an equilibrium shift. Aiming to overcome the low PDC commercial availability, which can only be acquired at low amounts and a high cost, a whole production process was developed. Zymobacter palmae PDC (ZpPDC) gene was cloned and overexpressed in Escherichia coli. After that, high amounts of the recombinant enzyme were obtained by the development of a high-cell density culture process in bench-top bioreactor. Regarding TA, four different enzymes were available from Chromobacterium violaceum (Cvi-TA), Vibrio fluvialis (Vfl-TA) and Aspergillus terreus (Ate-TA and Ate-TA_T247S). Both PDC and the different transaminases were characterized to find out the appropriate compromise conditions to construct the enzymatic cascade. Taking into account the found conditions, preliminary screening reactions were carried out, from which Cvi-TA and Vfl-TA were selected for the synthesis of 3-APB; and Vfl-TA for the synthesis of 1-PEA. After proving the feasibility of TA and PDC cascade reaction, different optimization approaches were applied in order to maximize reaction yields and to improve the low transaminase operational stability. On the one hand, reaction conditions optimization approaches were explored. On the other, reaction medium engineering was applied. After that, enzyme immobilization was carried out. Immobilized derivatives of both Cvi-TA and Vfl-TA were obtained in MANA-agarose and epoxy-agarose supports. In the case of PDC, an innovative simultaneous purification and immobilization process was developed using MANA-agarose. Finally, the obtained immobilized enzymes were applied in reactions and a reaction cycle strategy was developed.
Universitat Autònoma de Barcelona. Programa de Doctorat en Biotecnologia
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Lindegård, Boel. "Determination of amines and amine N-oxides in biological samples, particularly with supported liquid membranes for sample pretreatment." Lund : Dept. of Analytical Chemistry, Lund University, 1994. http://catalog.hathitrust.org/api/volumes/oclc/39111862.html.
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Taylor, Morgan James. "Chemistry of β-diketiminate Group 14 and Group 2 complexes and macrocyclic amines and amine ethers." Thesis, University of Sussex, 2012. http://sro.sussex.ac.uk/id/eprint/39640/.
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Group 14 metal(II) alkyl complexes are very rare, with few examples being studied in great detail. To this end, a series of β-diketiminate lead(II) alkyl and aryl complexes, [{(2,6-iPr2C6H3)NC(CH3)}2CH]PbR (R = Me, iPr, sBu, Np, Bn, tBu and Ph) were synthesised and a number of computational studies were performed on them to increase the understanding of the nature of these compounds. Reactivity studies on both the lead, and the analogous tin systems, showed that they could be used as precursors to generate examples of very rare two-coordinate group 14 metal cation complexes, including the first example of a β-diketiminate two-coordinate lead(II) cation, and an analogous example of a rare low-coordinate tin(II) system. These were studied in detail by computational methods, including the stabilising effects of a coordinated solvent molecule on the metal centre. β-Diketiminate magnesium alkyl complexes were generated to investigate the +2 oxidation state metal environment without the presence of a stereochemically active lone pair, as present in the group 14 metal(II) complexes. A carbodiimide was successfully inserted into the magnesium-carbon bond, and novel magnesium phosphides were generated from the alkyl complexes. Solvent stabilisation effects on these phosphides were also studied by computational methods. A series of macrocyclic amines and amine ethers were synthesised to investigate the hydrolysis of a phosphate diester model RNA system by lead(II) salts, monitored by UV-visible kinetics. The reaction kinetics gave no reproducible results, but the syntheses of the macrocycles are presented in detail for further citation.
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Rey, Carrizo Matías. "New polycyclic amines with biological activity." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/285111.
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Influenza is a major health problem worldwide, as the periodic pandemics of the 20th century have highlighted. Some countermeasures have been developed and have indeed diminish the devastating effects of the disease, such as modern health care, vaccination and novel medicines. Yet, the threat of a recombinant mutant virus that could affect millions of people and the recently discovered resistance of some virus strains to the current available treatments, render the need for new ways of fighting influenza A virus urgent.
In the present dissertation we have taken amantadine as a model, an antiviral drug in disuse at the moment due to the appearance of resistant strains, that targets a viral proton channel named M2. Thus, we have synthesized and evaluated several polycyclic amines as potential wild-type M2 channel blockers and amantadine-resistant mutants, like V27A, as well. We have succeeded in the obtention of highly potent wild-type and V27A inhibitors and most remarkable, some of them exhibited a dual activity on both M2 channels. Noteworthy, among the prepared compounds, a polycyclic guanidine presented the higher activity ever recorded against the V27A mutant.
Again working with polycyclic molecules but from a more theoretical point of view, the monomer, dimer and dihydrodimer of a highly strained pyramidalized alkene were synthesized and fully characterized. Importantly, the dimer featured four cyclohexanes in a frozen boat conformation and possessed hydrogen flagpole interactions that were relevant to theoretical organic chemists.La grip presenta un greu problema arreu del món, com les pandèmies del segle XX han demostrat. S’han pres algunes mesures per lluitar-hi que han realment disminuït els efectes devastadors de la malaltia, com son la hospitalització moderna, la vacunació i les noves medicines. Tot i així, l’amenaça d’un virus recombinant mutant que pugui afectar a milions de persones i la recentment descoberta resistència d’algunes soques del virus als tractaments actuals, han provocat que la necessitat per a noves maneres de lluitar contra la grip A sigui urgent. En la present Tesi, hem pres amantadina com a model, un medicament antiviral actualment en desús degut a l’aparició de soques resistents, que té com a diana un canal de protons del virus anomenat M2. Així doncs, hem sintetitzat i avaluat diverses amines policícliques com a potencials blocadors del canal salvatge M2 i mutants resistents a amantadine, com el V27A, també. Hem tingut èxit en l’obtenció de potents inhibidors del canal salvatge i del V27A i lo més destacable és que alguns han mostrat una activitat dual en ambos canals M2. Cap remarcar que, entre els compostos preparats,una guanidina policíclica va presentar l’activitat més alta mai enregistrada contra el mutant V27A. Seguint amb les molècules policícliques però des d’un punt de vista més teòric, el monomer, dimer i dihidrodimer de un alqué altament piramidalitzat van ser sintetitzats i completament caracteritzats. Cal subratllar que, el dimer posseïa quatre ciclohexans en conformació bot congelat i mostrava interaccions entre els hidrògens flagpole que eren rellevants per als químics orgànics teòrics.
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Sieczkowska, Barbara. "Functional polymer layers with protected amines." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1244668077080-12212.
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This work refers to the area of bio-nanotechnology and concerns the selective immobilization of DNA or other bio-template on microstructured gold contacts and which then permit a coordinated cooperation of several of these nanotemplate, e.g., within a microreactor. The immobilization of such nano-objects should be realized through functional thin polymer films which provide binding groups. Thus, the main aim of this work was the development of polymeric materials for thin functional films which permit to deposit on different substrates a wide variation of functional elements or metal structures and to achieve a pattern formation using optical grid methods. In order to realize this concept it was necessary to design and develop a polymer system based on suitable photolabile units and in addition having anchoring groups which attach on specific substrates like gold. In this terpolymer concept was aimed for which consists of three components with particular functions in suitable molar ratios, which allow the tune the properties of the materials, and provide: amino photolabile protected groups for the photolithographic creation of patterned areas with free amino groups, which are available for further modifications like attachment of colloids, metallization or attachment of DNA strands; disulfide derivative anchor groups providing anchoring capacity for gold surface and spacer groups for adjusting the film quality. These multifunctional terpolymers should be synthesised by free radical polymerisation of suitable monomers. Although these techniques are successful, they are limited by their complexity, rigorous synthetic demands, as well as incompatibility with many functional termolabile and highly reactive functionalities. To overcome these difficulties a polymerisation technique based on “living” free radical polymerisation has been used in this work. A highly efficient polymer-analogous modification allows to introduce the functionalities after the polymer construction reaction. The production of suitable prepolymers [poly(styrene-r-4-propargyl-oxystyrene)] was carried out with the help of a controlled synthesis methodology “nitroxide mediate radical polymerization" followed by polymer analogous reaction using one of the most efficient click reactions, the Cu(I) catalyzed Huisgen 1,3-dipolar cycloaddition between terminal acetylenes and azides to attach further functionalities through the formation of a stable 1,4-disubstituted 1,2,3-triazol ring . The combination of nitroxide mediated radical polymerization (NMRP) and click chemistry was used to produce well-defined random copolymer. It could already be shown that also block copolymers can be prepared which give the chance to combine nanostructure formation in block copolymers with special functionality. Thus, the special properties of these functional polymers like the capability for photopatterning and anchoring onto gold substrates make them very interesting for nanotechnology applicationsDiese Arbeit bezieht sich auf das Gebiet der Bionanotechnologie und betrifft ein neuartiges Verfahren zur selektiven Immobilisierung der DNA oder anderer Biomoleküle auf mikrostrukturierten Goldkontakten, welche dann ein koordiniertes Zusammenwirken von einzelnen Nanomolekülen ermöglichen, z.B. in einem Mikroreaktor. Die Immobilisierung solcher Nanoobjekte soll durch dünne Funktionsschichten realisiert werden, die die Anbindungsgruppen liefern. Folglich war das Hauptziel dieser Arbeit die Entwicklung von Polymermaterialien für dünne Funktionsschichten, die die Aufbringung einer großen Vielzahl von Funktionselementen oder metallischen Strukturen auf verschiedenen Substraten gestatten und die Strukturierung durch den Einsatz von lithographischen Methoden ermöglichen. Um dieses Konzept zu realisieren, war es notwendig, ein Polymersystem zu gestalten und zu entwickeln, welches auf geeignete photolabile Einheiten basiert und zusätzlich Ankergruppen hat, die mit spezifischen Substraten wie Gold verbunden ist. Dieses Terpolymerkonzept wurde gezielt aus drei Komponenten mit speziellen Funktionen in entsprechenden molaren Verhältnissen gebildet, die eine Abstimmung der Materialeigenschaften ermöglicht und folgendes bereitstellt: photolabile geschützte Aminogruppen für die photolitographische Strukturerzeugung mit freien Aminogruppen, welche für weitere Modifikationen verfügbar sind wie das Anhängen von Kolloiden, die Metallisierung oder Anfügung von DNA-Strängen; disulfide Derivate für die kovalente Anbindung auf der Goldoberfläche und Spacer-Gruppe für Verbesserung der Schichtenbildung. Diese multifunktionalen Terpolymere sollen durch eine freie radikalische Polymerisation von entsprechenden Monomeren synthetisiert werden. Obwohl diese Techniken erfolgreich sind, sind sie eingeschränkt durch ihre Komplexität, den strengen synthetischen Anforderungen, sowie der Inkompatibilität mit vielen funktionalen thermolabilen und hochreaktiven Funktionalitäten. Um diese Schwierigkeiten zu überwinden wurde eine Polymerisationstechnik für diese Arbeit genutzt, die auf der „lebenden“ freien radikalischen Polymerisation basiert. Eine hoch effiziente polymeranaloge Modifizierung erlaubt die Einführung von Funktionalitäten nach der Polymeraufbaureaktion. Die Herstellung von entsprechenden Präpolymeren Poly(Styrol-r-4-Propargyl-oxystyrol) wurde mittels einer kontrollierten Synthesemethodik „Nitroxid-mediated controled radical polymerisation“ (NMRP) durchgeführt, gefolgt von der Polymeranalogreaktion, die eine der effizientesten Click-Reaktion - die Cu(I) katalysierte 1,3-dipolar Cycloaddition von terminalen Alkinen an Aziden nach Huisgen nutzt, um weiter Funktionalitäten durch die Bildung eines stabilen 1,4-disubstituierten-[1,2,3]-Triazolringes anzufügen. Die Kombination von NMRP und Click-Chemie wurde zur Herstellung eines exakt definierten Random Copolymers genutzt. Es konnte bereits gezeigt werden, dass auch Blockcopolymere geschaffen werden können, die eine Möglichkeit zur Kombination von Nanostrukturformationen in Blockcopolymeren mit speziellen Funktionaltäten bieten. Folglich sind die speziellen Eigenschaften dieser Funktionalpolymere wie die Fähigkeit zur Photostrukturierung und Verankerung auf Goldsubstraten für nanotechnologische Anwendungen sehr interessant
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Knight, Frances Isobel. "Catalytic routes to enantiomerically pure amines." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308374.
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Glennie, Sarah. "Catalytic hydrogenation of nitriles to amines." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/54626/.
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The adiponitrile hydrogenation reaction, relevant for the production of aminocapronittile and hexamemyldiamine precursors for Nylon 6 and Nylon 6, 6 respectively, has been investigated. Three different reactor systems were used trickle-bed reactor, fixed-bed gas-phase reactor and the stirred-tank autoclave reactor. This meant comparisons between flow system and batch process could be made. Supported metal catalysts were investigated as alternatives for the currendy industrially used Raney catalyst. Precious metals, specifically rhodium, were compared with the base metals nickel and cobalt on the basis of activity and selectivity. Mixed metal alloy catalysts were also prepared and comparisons drawn. Finally a range of supports were also tested. Both flow systems were found to be of limited use with problems attributed to the practical applications of the reactor systems. Using Autoclave activity data as a standard it was possible to define differences in activity between each of the catalysts prepared.
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King, Angela Marie. "Chromogenic reagents for amines and cations." Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317009.
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Middleton, Mark L. "[2,3]-sigmatropic rearrangements of allylic amines." Thesis, University of Exeter, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245952.
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Probert, Gareth David. "The zirconocene-mediated synthesis of amines." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242623.
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Gibson, E. M. "Spectroscopy of jet-cooled aromatic amines." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47075.
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Kinsey, Francesca. "Novel axially chiral amines as organocatalysts." Thesis, University of East Anglia, 2016. https://ueaeprints.uea.ac.uk/67099/.
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Novel axially chiral amines as organocatalysts Keywords: Axial chirality, asymmetric organocatalysis, Reformatsky reaction, Diels- Alder reaction, amino acid. This body of research describes the recent developments our group has contributed towards the synthesis of novel axially chiral α- and β-functionalized amino acids and their application in asymmetric catalysis. This thesis is divided into three sections. The first chapter contains a review of the discovery and development of organocatalysis and includes key examples of its progression in terms of widening applications and improving selectivities. The second chapter consists of the results and discussion section of this thesis and it is divided into two parts. Part one contains works relating to the synthesis of a series of binaphthyl and biphenyl organocatalysts and describes key selective synthetic steps: a diastereoselective Reformatsky addition and asymmetric lithiation and chloroformate/carboxylation addition steps. Part two focuses on the observed enantio- and diastereoselectivity of these catalysts in the aldol, Michael and Diels- Alder reactions. Key steps: i) 10 mol% 239.HCl, MeOH:H2O, 0 °C ii) LiAlH4 reduction Section three contains the experimental data for the compounds described in chapter two.
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POURSOULIS, MICHEL. "Syntheses asymetriques d'acides alpha-amines cycliques." Paris 6, 1993. http://www.theses.fr/1993PA066695.
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Etude de la reactivite de la fonction hemiacetal de morpholines. Syntheses d'aminoacides mono et polycycliques derives de l'acide pipecolique. Reactions tandem d'aza-cope cyclisation et d'aza-cope hydrolyse
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SCHWARZ, JOHANNES. "Synthese asymetrique d'acides amines non-naturels." Université Louis Pasteur (Strasbourg) (1971-2008), 1994. http://www.theses.fr/1994STR13041.
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Cette these est consacree a la synthese asymetrique d'acides amines non-naturels. Elle comprend dans sa premiere partie l'etude du mecanisme de la monoalkylation d'un derive chiral de la glycine. Un modele propose a pu etre confirme. Cette methode a ensuite ete utilisee pour la synthese des enantiomeres r et s optiquement purs de deux acides amines (la naphtylalanine et la dichlorophenylalanine). Son utilite pour la preparation d'acides amines en quantite industrielle a ete montree. Le deuxieme chapitre presente la premiere synthese asymetrique du deux-methyltryptophane. La troisieme partie resume la tentative de synthese de la fluoroleucine. Il a ete possible de demontrer que cet acide n'existe pas sous la forme de son acide libre, mais cyclise spontanement pour former une lactone a cinq atomes
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Brunmark, Per. "Methods for assessment of exposure to aromatic amines/isocyanates by air monitoring and biomarkers." Lund : Dept. of Analytical Chemistry and Dept. of Occupational and Environmental Medicine, Lund University, 1994. http://catalog.hathitrust.org/api/volumes/oclc/38948330.html.
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Souza, Adriana Helena de [UNESP]. "Tamponamento cecal: aspectos clínico, fisiopatológico e terapêutico na laminite experimental em eqüinos." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/101104.
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Inúmeros estudos vêm sendo realizados objetivando esclarecer os mecanismos da laminite aguda em eqüinos. Muitos destes esclarecendo ou suscitando dúvidas sobre teorias já descritas; outros sugerindo novos mecanismos cruciais no desenvolvimento da laminite. Modelos in vitro e in vivo, focados na inflamação, distúrbios hemodinâmicos, ativação enzimática no dígito e eventos gastrintestinais somam-se para explicar sinais clínicos observados na laminite. Apesar da existência de dados correlacionando alterações metabólicas, mudanças da microflora e do pH cecal com a fisiopatologia da laminite poucas são as medidas profiláticas ou terapêuticas que visam restabelecer ou manter a função cecal. O objetivo deste estudo foi avaliar os efeitos da administração intracecal de solução tampão contendo hidróxido de alumínio e hidróxido de magnésio (Al(OH)3 e Mg(OH)2) na evolução da laminite induzida por sobrecarga de CHO balizado em parâmetros clínicos e laboratoriais; quantificando e qualificando aminas bioativas do conteúdo cecal; comparando número, tipo, localização e distribuição de células apoptóticas epidermais laminares e comparando a expressão gênica de MMP-2 e MMP-9 em tecido laminar digital. Os animais que desenvolveram laminite tiveram sinais de claudicação de ocorrência mais tardia no grupo que recebeu solução tampão, porém, ambos os grupos expostos ao CHO exibiram alterações laboratoriais características deste modelo experimental. As concentrações cecais da putrescina e cadaverina, o número de células epidérmicas laminares apoptóticas e a expressão gênica das MMP-2 e MMP-9 apresentaram-se elevadas nos eqüinos expostos à sobrecarga de CHO em relação aos do grupo controle, no entanto, foram menos evidentes no grupo tratado com solução tampão...
A large number of studies have been undertaken aimed at furthering our understanding of the complex mechanisms of acute laminitis in the horse. Many of these studies have either reinforced or cast doubt on previously theories on the pathogenesis of this disease, while others have suggested new mechanisms which may play a key role in its development. Studies utilising in vitro and in vivo models of the disease, particularly addressing the areas of inflammation, haemodynamic disturbances and enzyme activation in the hoof, as well as the events occurring in the hindgut, have helped to explain many clinical observations of the disease. Instead of the existence of results linking the metabolic alterations, microflora and cecal pH changes with laminitis physiopatology there are no effective therapies and means of prevention to reestablish or maintain the cecal function. The aim of this study was evaluate the effects of an intracecal buffer solution composed of aluminum and magnesium hydroxide on the development of carbohydrate overload (CHO)-induced laminitis by characterization and comparison of clinical parameters, bioactives amines in cecal content, apoptotic epidermal cells and gene expression of MMP-2 e MMP-9 in digital laminar tissues. All CHO-treated horses developed lamenees, but it was significantly delayed in group that received buffering treatment. However, both CHO-treated group presented similar laboratorial changes which are particular to this experimental model. The cecal putrescine and cadaverine level, the number of laminar apoptotic epidermal cells, and gene expression of MMP-2 and MMP-9 were increased in CHO-treated horses compared to control group, but it was less in the buffer-treated group...(Complete abstract, access undermentioned eletronic address)
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Souza, Bruno Corte Alves de [UNESP]. "Estudo da interação de amino derivados de quitosana com o plasmídeo VR1412." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/110690.
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000790040.pdf: 1326937 bytes, checksum: af8ee251aaaf5a06acd1e6604ded62a3 (MD5)O presente estudo teve como objetivo principal a síntese e caracterização de derivados hemocompatíveis de quitosana e sua utilização na preparação de nanopartículas para terapia gênica não-viral. O trabalho foi realizado em duas etapas, sendo a primeira a obtenção dos derivados, seguido de estudos da interação com o plasmídeo VR 1412 (pDNA) que expressa a β-galactosidase. A primeira etapa de síntese envolve a modificação de quitosana pela introdução de grupos amino, seguido pela ligação de cadeias de polietilenoglicol (PEG). Os derivados foram caracterizados por espectrometria de ressonância magnética nuclear de hidrogênio, potenciometria e viscosidade. Os estudos da interação foram realizados utilizando as técnicas de fluorescência, eletroforese em gel de agarose, espalhamento de luz dinâmica e citotoxicidade. O trabalho foi conduzido de forma comparativa, avaliando as mudanças estruturais e seus efeitos na força de interação e estabilidade das nanopartículas
The current study aimed at the synthesis and characterization of hemocompatible chitosan derivatives and their use in the preparation of nanoparticles for non-viral gene therapy. The project was carried out in two steps, first the synthesis and characterization of the derivatives, followed by studies of the interaction between the chitosan derivatives and the VR1412 plasmid (pDNA), that expresses the β-galactosidase protein. The first step of synthesis was the modification of chitosan by introducing tertiary amino groups, followed by attaching the polyethyleneglycol (PEG) to the chitosan backbone. The study of the interaction between the chitosan derivatives and the pDNA was carried out using the fluorescence, electrophoresis in agarose gel, and light scattering techniques. The study was performed in order to evaluate the effect of structural changes of the chitosan backbone on the strength of interaction and stability of the nanoparticles
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Souza, Bruno Corte Alves de. "Estudo da interação de amino derivados de quitosana com o plasmídeo VR1412 /." São José do Rio Preto, 2014. http://hdl.handle.net/11449/110690.
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Orientador: Marcio José TieraBanca: Mário Sergio Galhiane
Banca: Elói da Silva Feitosa
Resumo: O presente estudo teve como objetivo principal a síntese e caracterização de derivados hemocompatíveis de quitosana e sua utilização na preparação de nanopartículas para terapia gênica não-viral. O trabalho foi realizado em duas etapas, sendo a primeira a obtenção dos derivados, seguido de estudos da interação com o plasmídeo VR 1412 (pDNA) que expressa a β-galactosidase. A primeira etapa de síntese envolve a modificação de quitosana pela introdução de grupos amino, seguido pela ligação de cadeias de polietilenoglicol (PEG). Os derivados foram caracterizados por espectrometria de ressonância magnética nuclear de hidrogênio, potenciometria e viscosidade. Os estudos da interação foram realizados utilizando as técnicas de fluorescência, eletroforese em gel de agarose, espalhamento de luz dinâmica e citotoxicidade. O trabalho foi conduzido de forma comparativa, avaliando as mudanças estruturais e seus efeitos na força de interação e estabilidade das nanopartículas
Abstract: The current study aimed at the synthesis and characterization of hemocompatible chitosan derivatives and their use in the preparation of nanoparticles for non-viral gene therapy. The project was carried out in two steps, first the synthesis and characterization of the derivatives, followed by studies of the interaction between the chitosan derivatives and the VR1412 plasmid (pDNA), that expresses the β-galactosidase protein. The first step of synthesis was the modification of chitosan by introducing tertiary amino groups, followed by attaching the polyethyleneglycol (PEG) to the chitosan backbone. The study of the interaction between the chitosan derivatives and the pDNA was carried out using the fluorescence, electrophoresis in agarose gel, and light scattering techniques. The study was performed in order to evaluate the effect of structural changes of the chitosan backbone on the strength of interaction and stability of the nanoparticles
Mestre
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Froehlich, Josiel Dimas. "Otimização do custo de aminas neutralizantes utilizadas em sistemas de topo de torres de destilação." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/170928.
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O processo de destilação do petróleo bruto é geralmente sujeito à atividade corrosiva dos equipamentos pelos ácidos, naturalmente presentes no petróleo. Este problema da corrosão pode ser atenuado pela adição de misturas de aminas neutralizantes que são inibidores da corrosão. Porém, esta adição significa um custo adicional ao processamento de petróleo. Para reduzir este custo direto da injeção de aminas o presente trabalho tem como objetivo aplicar a minimização do custo de misturas de aminas, utilizando dois diferentes métodos numéricos de otimização. Para isto foi utilizado um software desenvolvido no Laboratório Virtual de Predição de Propriedades (LVPP), onde os seguintes parâmetros operacionais são levados em consideração: temperatura de formação de sal, temperatura de orvalho do vapor d’água e pH do condensado da mistura. Esses parâmetros operacionais foram calculados e utilizados como restrições de desigualdade em otimizações com os métodos de Nelder-Mead (NM) e enxame de partículas (PSO). A escolha desses dois métodos numéricos foi devido a apresentarem características diferentes de busca do ótimo da função objetivo. O método NM apresenta caráter de busca local e o método PSO caráter de busca global. Assim, as duas restrições de desigualdade de otimização aplicadas foram: 1) o pH do condensado da mistura deve ser maior ou igual ao valor ótimo de 6,5; 2) a temperatura de formação de sal deve ser menor que temperatura do ponto de orvalho do vapor d’água. Quatro diferentes casos foram estudados, com estimativas iniciais das misturas escolhidas para satisfazer os itens 1) e 2). Os parâmetros operacionais calculados para as misturas de aminas apresentaram valores de pH abaixo dos valores considerados aceitáveis. Isso exigiu a implementação de uma condição de pH que aumentasse seu valor até a condição satisfatória, conforme restrição 1). A outra condição referente a restrição 2) foi satisfeita no cálculo das misturas para todos os casos estudados, exceto para o caso 2, de modo que a água na fase líquida arraste os sais potencialmente formados. Caso essa condição não fosse cumprida ocorreria a precipitação desses sais incrustando à superfície interna das tubulações e equipamentos, ocasionando um ataque corrosivo. As otimizações dos custos das misturas foram calculadas utilizando-se os próprios dados das misturas, com as condições dos itens 1) e 2) satisfeitas, como estimativa inicial. Para todos casos estudados, o método PSO foi capaz de obter resultados com custos menores que a metade do valor obtido com o método NM.Crude distillation equipment is usually subject to the corrosive activity of acids. This problem can be mitigated by the addition of amines. With the addition of amines to this process a cost is generated, therefore to reduce this cost of neutralizing the amines the present work applies two different optimization methods, Nelder-Mead (NM) and Particle Swarm Optimization (PSO). This was accomplished using an in house software, developed in the Virtual Laboratory of Property Prediction (LVPP), where the following operating conditions are taken into account: salt formation temperature, condensation temperature of the water and pH of the condensate of the mixture. The operational parameters were calculated and used as inequality constraints in optimizations with both Nelder-Mead (NM) and a particle swarm optimization (PSO) methods. Two inequality constraints were considered: 1) The condensate pH of the mixture should be higher or equal than 6.5; 2) The salt temperature should be less than the dew temperature of water vapor. Four different cases were studied, throught estimates initials of the mixtures to satisfy items 1) and 2). It has been found that the operating parameters calculated for several amine mixtures produced pH values below the one considered optimal. This required the implementation of a pH condition that would increase its value up to the condition satisfactory, in accordance with restriction 1). The other condition concerning restriction 2) was satisfied in the calculation of the mixtures for all studied cases, except to case 2, through which the water in the liquid phase entrains the salts formed. If this condition were not met, the precipitation of salts would occur on the internal surface of pipes and equipments, causing a corrosive attack. The cost optimizations of the amine mixtures were calculated using their own data, with the constraints of items 1) and 2) satisfied by an initial estimate. Of all the cases studied, the PSO method obtained results with costs lower than half values obtained with the NM method.
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Montillet, Louis-Thierry. "Fonctionnalisation de dérivés d'amines par oxidation électrochimique et réactions chimiques envisageables à partir des dérivés obtenus." Paris 5, 1995. http://www.theses.fr/1995PA05P180.
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