To see the other types of publications on this topic, follow the link: Aromatic amines.
Dissertations / Theses on the topic 'Aromatic amines'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Aromatic amines.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Marczylo, Timothy Hywel. "Bioactivation of aromatic amines." Thesis, University of Surrey, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336523.
Full text
2
Walsh, Kelly Ann. "The alkylation of aromatic amines." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7659.
Full textAbstract:
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.
3
Gibson, E. M. "Spectroscopy of jet-cooled aromatic amines." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47075.
Full text
4
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.
Full text
5
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.
Full text
6
Yeatts, Karin Beatrice. "An investigation of structure activity relationships for aryl nitrenium stability and mutagenicity for amino polyaromatic hydrocarbons." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-02132009-170829/.
Full text
7
Howell, Rachel. "Laser induced fluorescence studies of jet-cooled aromatic amines." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46347.
Full text
8
Rohaly, Matthew Joseph. "Decomposition of Aromatic Amines in a Jet Fuel Surrogate." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1417777531.
Full text
9
Sakamaki, Daisuke. "Studies on Electronic Properties of Aromatic Amines with Unique Structures." 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/174890.
Full text
10
Powell, C. J. "Studies of the nephrotoxicity of some alkyl and aromatic amines." Thesis, University of Surrey, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332745.
Full text
11
GHAANI, MASOUD. "Food Packaging Innovations- Electrochemical Nanosensors far Primary Aromatic Amines Quantification." Doctoral thesis, Università degli Studi di Milano, 2018. http://hdl.handle.net/2434/584740.
Full textAbstract:
Primary aromatic amines (PAAs) are substances that can be transferred from food packaging materials into foodstuffs and are “possibly carcinogenic to humans”. The formation of PAAs from multilayer packaging materials consisting of aromatic polyurethane (PU) adhesives occurs from the reaction between residual isocyanic monomers (the most widely used of which are 2,4-toluene diisocyanate – TDI and 4,4’-methylene diphenyl diisocyanate – MDI) that have migrated to the surface of the inner layer of the package and water molecules making contact with the same plastic surface. However, for foods subjected to thermal treatments, an alternative formation of PAAs should also be taken into consideration. Due to the detrimental effect of the temperature, some secondary bonds (namely allophanate and biuret bonds) displaced on the main PU backbone may be disrupted, originating neo-formed isocyanic monomers (such as TDI and MDI). The migration of these monomers from the adhesive layer across the inner sealing film can lead to PAAs as soon as they come into contact with the water molecules of the liquid or high aw packaged food. Although the existence and the mechanisms of the formation of allophanate and biuret linkages during the polymerization process with poly-isocyanates has been known for a long time, the negative impact on public health possibly arising from the migration of the neo-formed isocyanic monomers into the foods during thermal treatments seems to have not been fully perceived, with special regard to preservative heat treatments such as pasteurization and sterilization.
Regardless of the origin, the quantification of the risks associated with the potential formation of PAAs must be made by strict compliance with the provisions included in the current European legislation. However, both the non-selectivity of the widely adopted spectrophotometric method and the number of drawbacks associated with the more sophisticated techniques used at academic level and highly specialized laboratories impose the necessity for alternative analytical tools for the PAAs quantification.
In this thesis, after an introductive part on electrochemistry and the use of electrochemical sensors in food science, an in-depth review of the issues associated to the PAAs migration possibly occurring from food packaging materials is presented in chapter 1. In the following three chapters, the focus has been addressed to the implementation of electrochemical routes for the determination of PAAs by the development of modified electrochemical sensors characterized by high selectivity and sensitivity. More specifically, chapter 2 deals with the fabrication of a modified glassy carbon electrode (GCE) for the selective quantification of TDA. Different levels of complexity were investigated by modifying the electrode’s surface with multi-walled carbon nanotubes (MWCNTs), MWCNTs in chitosan (CS) and using gold nanoparticles (AuNPs).
In chapter 3 is described the development of a nanosensor for the MDA determination using multi-walled carbon nanotubes, chitosan, and gold nanoparticles for the modification of a glassy carbon electrode (MWCNTs-CS-Au/GCE).
In chapter 4, a new electrochemical sensor is proposed to determine MDA using a templating-based method known as ‘molecularly imprinted polymer’, together with multi-walled carbon nanotubes as conductive nanoparticles (MIP/MWCNTs/GCE). The three electrochemical sensors have been described in detailed fashion as far as both a polymer science perspective and analytical performance are concerned.
12
Hubbard, Sara E. "The solid-matrix luminescence of heterocyclic aromatic amines in sugar glasses." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1597616951&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Full text
13
Nicolae, Toma Gabriel. "Cobalt-Catalyzed Carbon-Nitrogen Bond-Forming Reaction between Secondary Amines and N-Aromatic or Aromatic Chlorides." Kyoto University, 2011. http://hdl.handle.net/2433/142304.
Full textAbstract:
Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(人間・環境学)<br>甲第16176号<br>人博第559号<br>新制||人||134(附属図書館)<br>22||人博||559(吉田南総合図書館)<br>28755<br>京都大学大学院人間・環境学研究科相関環境学専攻<br>(主査)教授 山口 良平, 教授 田村 類, 准教授 藤田 健一<br>学位規則第4条第1項該当
14
Wagner, Elizabeth Diane. "Modulation of genotoxic responses by environmental agents." Thesis, University of Surrey, 1999. http://epubs.surrey.ac.uk/843395/.
Full textAbstract:
A metabolite of a widely used pesticide, paraoxon, exerted a dramatic mutagenic synergistic effect in Salmonella typhimurium with a number of mammalian-activated or plant-activated aromatic amines and heterocyclic amines. The mutagenic synergy required an activated an aromatic amine, and was not attributable to the generation of new mutagenic products or to the modification of the stability of the activated aromatic amine products. Paraoxon modulated the genotoxic potency of dietaiy heterocyclic amines in human cells. The results of this study raise the concern of the environmental effects of organophosphorus ester insecticides. A clone of the Chinese hamster ovary cell line, AS52, was isolated, characterised and analysed under identical treatment conditions with the mutagens 2-acetoxy-acetylaminofluorene (2AAAF), ethyl methanesulphonate (EMS), and UV radiation. The genetic endpoints included acute DNA damage detected in the alkaline single cell gel electrophoresis (SCGE) assay, whole cell clastogenicity detected with laser beam flow cytometry and forward mutation at a target gene. There were statistically significant increases in DNA damage and forward mutation with all three mutagens. Statistically significant increases in chromosome damage were observed with 2AAAF and EMS but not with UV. A non-uniform distribution of DNA damage throughout the genome was indicated with the chemical mutagens in the SCGE assay. Another type of modulation in genotoxic response was investigated whereby numerous commercial soybean processing products and by-products were analysed for their antimutagenic and antigenotoxic activities. Antimutagenic activity was detected in a soybean processing by-product, soybean molasses and in an ethanol extract, fraction PCC. PCC protected mammalian cells against direct DNA damage, clastogenic damage and point mutation induced by 2AAAF. A fraction of PCC, PCC100 was an effective antimutagen in mammalian cells and in human lymphocytes. Analytical chemical studies identified the compounds responsible for the antimutagenic activity as the soyasaponins I, III and V.
15
Ayrton, Andrew David. "Food mutagens : factors that modulate their metabolic activation." Thesis, University of Surrey, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328576.
Full text
16
Debruin, Lillian S. "The detection of aromatic amines, possible mammary carcinogens, in human milk." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ58303.pdf.
Full text
17
Robotham, Ian A. "Mechanistic studies of aromatic substitutions with aniline and phenoxide nucleophiles." Thesis, Durham University, 1997. http://etheses.dur.ac.uk/5063/.
Full textAbstract:
Kinetic studies are reported of the reactions of 1,3,5-trinitrobenzene with aniline in dimethyl sulfoxide (DMSO). In the presence of buffers containing 1,4- diazabicyclo(2.2.2)octane, (Dabco), and its acid salt, DabcoH(^+), the anilide σ-adduct is formed. The reaction of ethyl 2,4,6-trinitrophenyI ether with aniline in DMSO containing Dabco occurs in two stages. The first gives σ-adduct intermediate on the substitution pathway, which has been identified spectroscopically. The second yields 2,4,6-trinitrodiphenyIamine, the substitution product. Kinetic studies show that proton transfer is rate-limiting both in the formation of the intermediate and in its subsequent acid-catalysed decomposition. Phenoxide is a considerably better leaving group than ethoxide and the substitution reactions of phenyl 2,4,6- trinitrophenyl ethers and phenyl 2,4-dinitronaphthyI ether with aniline in DMSO occur without the accumulation of intermediates. The kinetics indicate both uncatalysed and base catalysed pathways. Values have been determined for the pK(_a) in DMSO of several ammonium ions derived from amines which have previously been widely used as nucleophiles in nucleophilic aromatic substitution reactions; values are also given for four polynitrodiphenylamines used as indicators. Second order rate constants (K(_s)) are presented for the reaction of substituted phenyl 2,4,6-trinitrophenyl ethers with a series of phenolate ions having pK(_a) values both higher and lower than that of the respective leaving groups in aqueous solution. The rate constants for the reverse reaction (k(_-s)) have also been measured. The Brømsted diagram formed when plotting log k(_s) versus pK(_a) shows a change in slope when ΔpK(_a) = 0 (ΔpK(_a) being the difference in pK(_a) values of the leaving group and nucleophile). This is consistent with a two step process involving a discrete σ-adduct intermediate. From the measured β values effective charges have been determined and the overall effective charge map constructed. Kinetic studies have been made for the reactions of substituted phenyl 2,4,6- trinitrophenyl ethers with substituted phenolate ions in 74% DMSO-water (v/v). Two reactions are observed. The evidence suggests that the more rapid involves formation of a 1,1 σ-adduct between the substrate and the phenolate ions. The slower reaction is attributed to hydroxide attack at the 3-position of the substrate.
18
Sen, Subhabrata. "Sythesis of diaryl ethers and diaryl amines via Dötz benzannulation /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3030540.
Full text
19
Tugnait, Meera. "Multinuclear magnetic resonance studies on the metabolism model of fluoroaromatic xenobiotics." Thesis, Birkbeck (University of London), 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296519.
Full text
20
Collier, Simon Andrew. "The reactions of N-chloroamines and related N-substituted amines with aromatic substrates." Thesis, University of York, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333736.
Full text
21
Lu, Fei. "Formation and control of heterocyclic amines and polycyclic aromatic hydrocarbons during meat processing." Thesis, University of Reading, 2018. http://centaur.reading.ac.uk/77712/.
Full textAbstract:
Heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) formed during meat processing may pose health risk to the public. This project aimed to investigate the occurrence of HCAs and PAHs in highly consumed cooked meat products including ready-to-eat (RTE) meat, patties and meatballs, and their health risk was also assessed according to the dietary pattern. Different strategies including replacing fat with vegetable oils and adding spices were applied in order to reduce the formation of HCAs and PAHs in final meat products. In addition, inhibitory mechanism of antioxidants in oil and spices on the formation of HCAs and PAHs in meat system were also discussed. In this work, HCAs and PAHs were extracted by solid-phase extraction and analysed by HPLC- Diode array UV/ Fluorescence detector. For RTE meat in UK, chargrilled chicken had the highest level of HCAs (37.45±4.89ng/g) and PAHs (3.11±0.49ng/g), followed by roasted bacon (HCAs 15.24±1.31ng/g, PAHs 1.75±0.17ng/g) in selected RTE meat products. Increase intake of chargrilled chicken and ham could increase breast cancer and colorectal adenoma risk, but other types of meat had relatively lower health risk. Replacing pork back fat with vegetable oils including sunflower oil, olive oil and grape seed oil could not only improve fatty acids profile in cooked meat products, but also reduce HCAs, which could be attributed to the existence of tocopherols and polyphenol compounds in the vegetable oils. However, antioxidants in the oils could not reduce the total amount of PAHs effectively, while the complexity of oil decomposition and antioxidants performance at high temperature could partially explain the case. All 6 spices powder including garlic, onion, red chilli, paprika, black pepper and ginger reduced the formation of total HCAs, while ginger powder achieved the highest inhibition efficiency compared with all other spices. Antioxidant capacity of spices determined their efficiency in prohibiting formation of HCAs and PAHs in great extent, while meat type only affected the formation of HCAs (p < 0.05), but not PAHs (p > 0.05). Regression model suggested that both diallyl disulfide and gallic acid contributed similar inhibitory efficiency on the formation of HCAs and PAHs. Synergistic effect between diallyl disulfide and gallic acid was observed on reducing HCAs (p < 0.05), but not on PAHs (p > 0.05).
22
Winter, Helen Rayma. "Strategies to reduce arylamine drug toxicity in people with AIDS /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/7937.
Full text
23
Mohammadi, Nargesi Behrouz [Verfasser], and Georg A. [Akademischer Betreuer] Sprenger. "Biotechnological production of aromatic amines and aromatic alcohols by recombinant Escherichia coli strains / Behrouz Mohammadi Nargesi ; Betreuer: Georg A. Sprenger." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2019. http://d-nb.info/1181099374/34.
Full text
24
Pabel, Ulrike. "Stabile Expression von Sulfotransferasen - allein oder in Kombination mit Cytochrom P450 - in Zelllinien für Mutagenitätsuntersuchungen." Phd thesis, Universität Potsdam, 2003. http://opus.kobv.de/ubp/volltexte/2005/93/.
Full textAbstract:
<P align=justify>Aromatische Amine und Amide (aAA) sind aufgrund ihrer starken Verbreitung in der menschlichen Umwelt und ihres kanzerogenen Potenzials von großer toxikologischer Bedeutung. Die Kanzerogenität der aAA wird durch die Mutagenität hochreaktiver Stoffwechselprodukte vermittelt, die in zwei sequenziellen katalytischen Reaktionen entstehen. Die erste ist meistens eine <I>N</I>-Hydroxylierung, die oft durch Cytochrom P450 1A2 (CYP1A2) katalysiert wird. Daran schließt sich eine <I>O</I>-Konjugation durch Sulfotransferasen (SULT) oder <I>N</I>-Acetyltransferasen (NAT) an. Die Bioaktivierung ist ein kritischer Parameter für die Übertragbarkeit von Ergebnissen aus Tiermodellen auf den Menschen. </P><P align=justify>Rekombinante <I>in vitro</I> Systeme, die fremdstoffmetabolisierende Enzyme verschiedener Spezies exprimieren, ermöglichen die vergleichende Untersuchung der Bioaktivierung im Menschen und in Versuchstieren. Ziel des Projektes war die Aufklärung der Bioaktivierung der aAA durch humane Enzyme. Im Vordergrund stand die Untersuchung der Rolle humaner SULT in diesem Prozess. Es wurden rekombinante <I>in vitro</I> Systeme, konstruiert, die CYP1A2 und SULT des Menschen koexprimieren. SULT-cDNAs wurden in den Säugerzell Expressionsvektor pMPSV kloniert und in Standardindikatorzellen für Mutagenitätsuntersuchungen (V79 Zellen aus dem Chinesischen Hamster) transfiziert. Das Expressionsniveau von CYP1A2 und SULT wurde mittels Immunblotanalyse und radiometrischen Aktivitätsmessungen charakterisiert. In den rekombinanten Zellen wurden vier aAA als Modellsubstanzen (2-Acetylaminofluoren, 2-Aminoanthracen, 3′-Methyl-4-dimethylaminoazobenzol, 2,4-Diaminotoluol) auf ihre Mutagenität am <I>hprt</I>-Locus hin untersucht.</P><P align=justify>Die aAA waren in Zellen, die keine rekombinanten Enzyme oder lediglich CYP1A2 exprimierten, nicht mutagen. In Zellen, die CYP1A2 und SULT der Subfamilie 1A koexprimierten, erzeugten sie bereits in geringen Konzentrationen klare mutagene Effekte (0,3 µM für 2-Acetylaminofluoren <br />
und 3′-Methyl-4-dimethylaminoazobenzol; 0,1 µM für 2-Aminoanthracen; 10 µM für 2,4-Diaminotoluol). Die stärkste Aktivierung von 2-Acetylaminofluoren und 3′-Methyl-4-dimethylaminoazobenzol erfolgte in der Zelllinie, die CYP1A2 und SULT1A2 koexprimierte; die stärkste Aktivierung von 2,4-Diaminotoluol und 2-Aminoanthracen erfolgte in der Zelllinie, die CYP1A2 und SULT1A1 koexprimierte. </P><P align=justify>Sowohl SULT1A1 als auch SULT1A2 sind im Menschen genetisch polymorph. Ein unterschiedlich starkes Aktivierungspotenzial der Alloenzyme könnte eine individuell unterschiedliche Suszeptibilität für die durch aAA ausgelöste Kanzerogenese bedingen. In HPRT-Mutationsuntersuchungen mit rekombinanten Zellen zeigten die allelischen Varianten der SULT1A2 starke Unterschiede in ihrem Aktivierungpotenzial. Nur in der Zelllinie, die das Alloenzym SULT1A2*1 mit CYP1A2 koexprimierte, wurde 2-Acetylaminofluoren zum Mutagen aktiviert. Zur Aktivierung von 3′-Methyl-4-dimethylaminoazobenzol waren jedoch sowohl das Alloenzym SULT1A2*1 als auch das Alloenzym SULT1A2*2 in der Lage. Die Alloenzyme der SULT1A1 zeigten ein ähnlich gutes Aktivierungspotenzial für aAA. </P><P align=justify>In früheren Studien wurde gezeigt, dass die SULT1C1 der Ratte eine wichtige Rolle bei der Aktivierung der aAA in dieser Spezies spielt. Dahingegen war die humane SULT1C1 nicht in der Lage die untersuchten aAA zu aktivieren. Die Kenntnis solcher Spezieunterschiede könnte wichtig sein um unterschiedliche Organotropismen aAA in Menschen und Tiermodellen zu erklären, da SULT mit starker Gewebespezifität exprimiert werden und das Expressionsmuster für die einzelnen SULT-Formen in Menschen und Ratten sich stark unterscheidet.</P><br><br><P align=justify>Aromatic amines and amides (aAA) represent a group of chemicals with great toxicological importance due to their wide distribution in the environment and their carcinogenic potency. The carcinogenicity of aAA is mediated by the mutagenic action of highly reactive metabolites. They are frequently formed by <I>N</I>-hydroxylation of the exocyclic amino group, usually catalysed by cytochrome P450 1A2 (CYP1A2) and subsequent <I>O</I>-conjugation by phase-II enzymes e.g. sulfotransferases (SULT) or <I>N</I>-acetyltransferases. </P> <P align=justify>The bioactivation constitutes a critical parameter for the transfer of results from animal models on man. Recombinant <I>in vitro</I> systems expressing xenobiotic metabolizing enzymes of different species allow the comparative study of the bioactivation in humans and animal models. <BR>The aim of this project was to elucidate the bioactivation of aAA by human xenobiotic enzymes. The investigation focused on the role of SULT in this process. SULT-cDNAs were cloned into the mammalian expression vector pMPSV and transfected in V79 Chinese Hamster cells, which represent standard indicator cells for mutagenicity tests. Selected SULT-cDNAs were also co-expressed with human CYP1A2. These cells were able to catalyse internally both enzymatic reactions that are necessary for the bioactivation of aAA. The expression level of CYP1A2 and SULT in the co-expressing cell clones was characterised by immunoblot analysis and radiometric SULT-activity measurement. The mutagenicity of four aAA model compounds, 2-aminoanthracene, 2-acetylaminofluorene, 3'-methyl-4-dimethylaminoazobenzene and 2,4-diaminotoluene, at the <I>hprt</I> locus of the recombinant cell lines was investigated.</P><br />
<P align=justify>These aAA were not or only marginally mutagenic in wild type cells or in recombinant cells expressing CYP1A2 alone. If CYP1A2 was co-expressed with SULT forms of the 1A subfamily clear mutagenic effects occured in low concentrations of the aAA (0,3 µM for 2-acetylaminofluorene and 3′-methyl-4-dimethylaminoazobenzene; 0,1 µM for 2-aminoanthracene; 10 µM for 2,4-diaminotoluene). The strongest activation of 2-acetylaminofluorene and 3'-methyl-4-dimethylaminoazobenzene was mediated by SULTA2 and of 2-aminoanthracene and 2,4-diaminotoluene by SULT1A1. </P><br />
<P align=justify>SULT1A1 and SULT1A2 are expressed polymorphically in humans. Differences in the activation potency of distinct alloenzymes for aAA may cause divergent individual susceptibilities for cancer induced by aAA. Briefly, the allelic variants of SULT1A2 showed substantial differences regarding their activation potencies for the investigated aAA. Only alloenzyme SULT1A2*1 was able to activate 2-acetylaminofluorene to a mutagen whereas 3′-methyl-4-di-methylaminoazobenzene was activated by alloenzymes SULT1A2*1 and SULT1A2*2. The investigated alloenzymes of SULT1A1 showed equal activation potencies for aAA. </P><br />
<P align=justify>In previous studies it had been shown that the SULT1C1 plays an important role in the activation of aAA in rats. However, the human SULT1C1 was not able to activate the investigated aAA in the study presented here. Such species differences might be important for the elucidation of divergent organotropisms of aAA in humans and animal models, since SULT are expressed with strong tissue specificities and the pattern of expression in humans and rats is severely different.</P><br>
25
Kurata, Ryohei. "Studies on Electronic Properties of Nitrogen-and Boron-Containing π-Electron Systems". Doctoral thesis, 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225623.
Full textAbstract:
京都大学<br>0048<br>新制・課程博士<br>博士(工学)<br>甲第20398号<br>工博第4335号<br>新制||工||1672(附属図書館)<br>京都大学大学院工学研究科分子工学専攻<br>(主査)教授 関 修平, 教授 今堀 博, 准教授 伊藤 彰浩, 教授 白川 昌宏<br>学位規則第4条第1項該当<br>Doctor of Philosophy (Engineering)<br>Kyoto University<br>DGAM
26
李偉安 and Wai-on Lee. "Oxidation chemistry and electrochemistry of ruthenium and chromium complexes of macrocyclic tertiary amines and aromatic diimines." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1989. http://hub.hku.hk/bib/B31231846.
Full text
27
Lee, Wai-on. "Oxidation chemistry and electrochemistry of ruthenium and chromium complexes of macrocyclic tertiary amines and aromatic diimines /." [Hong Kong : University of Hong Kong], 1989. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12505286.
Full text
28
Lord, Simon D. "Some studies of the reactions of amines with aldehydes and with aromatic nitro-compounds in acetonitrile." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5241/.
Full textAbstract:
Kinetic and equilibrium studies of the reactions between three trinitroaromatic species, 1,3,5-trinitrobenzene, ethyl 2,4,6-trmitrophenyl ether and phenyl 2,4,6- trinitrophenyl ether and the ahphatic amines n-butylamine, pyrrolidine and piperidine, in acetonitrile were undertaken. It was found that the reactions between 1,3,5-trinitrobenzene and each amine were too fast to measure. However kinetic information was gamed from the decomposition of the c-adducts formed from1.3.5- trinitrobenzene and both pyrrolidine and piperidme. Both the 3-adduct and the 1-adduct are observed as intermediates m the reaction of the ethyl ether with each amine, though formation of the 3-adduct was too fast to measure by stopped flow spectrometry. Formation of the picramides is subject to general acid catalysis due to the poor leaving group ability of the ethoxide ion. Only the 3-adduct intermediate was observed in the formation of each picramide from the phenyl ether. The fact that the 1-adduct is not seen is attributed to the phenoxide ion being a weaker base and hence a much superior leaving group to the ethoxide ion. The equilibrium constants K(_c,3)º and K(_c,1)º are a factor of ca. 10(^4) smaller in acetonitrile than dimethyl sulphoxide. This is due to acetonitrile being inferior to dimethyl sulphoxide in its ability to solvate charged species. The value of k(AM) for reaction at an unsubstituted position approaches the diffusion controlled Unit of acetonitrile. The reactions of propanal, 2-chloroethanal, 2,2-dichloroethanal and 2,2,2- trichloroethanal (chloral) with ammonia and several primary amines were studied. Only the reactions of ammonia with propanal and 2-chloroethanal produced the corresponding 2,4,6-trisubstituted-l,3,5-hexahydrotriazme.Reactions of the aldehydes with primary ammes yield propylidene imines as relatively stable species. Trimerisation was not observed however the imine may undergo dimerisation together with elimination of amine. Kinetic and equilibrium studies are reported on the formation in acetonitrile of2.4.6- triethyl-l,3,5-hexahydrotriazine, (TEHT), from propanal and ammonia, and also the corresponding decomposition reaction. The equilibrium constant was found to decrease with increasing water content in the acetonitrile which can be attributed to stabilisation of ammonia by the water. Good correlation was achieved for values of the equilibrium constant calculated directly from absorbance measurements and from combination of rate constants obtained from the formation and decomposition reactions.
29
Duncanson, Philip. "Synthesis of novel dyes and a study of the photochemistry N-formylated aromatic amines and indoles." Thesis, City University London, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302729.
Full text
30
Riddar, Jakob B. "Isocyanates, Amines and Alkanolamines : Sampling, Chromatography and Detection." Doctoral thesis, Stockholms universitet, Institutionen för analytisk kemi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-94067.
Full textAbstract:
Isocyanates, aromatic-, aliphatic- and alkanolamines are commonly used in the industry today. Millions of workers in Europe are exposed. The most frequent health symptoms are respiratory and dermal disorder. Due to the health risk most of the compounds in this thesis are regulated by authorities and have occupational exposure limits (OELs). Consequently, reliable and robust air sampling methods are urgently needed. In this thesis dry samplers for isocyanates, aliphatic- and alkanolamines have been developed and evaluated. The isocyanate sampler is now a commercial product (ASSET EZ4-NCP Dry Sampler, Supelco). The samplers were based on a denuder with a filter in series. The denuder and filter were impregnated with di-n-butylamine for the isocyanate sampler and with sulphuric acid for the aliphatic- and alkanolamine sampler. The robustness of the dry samplers was extensively evaluated. This was performed in a climate chamber containing a controlled atmosphere of the studied compounds. New methods based on hydrophilic interaction liquid chromatography (HILIC) coupled with tandem mass spectrometry (MSMS) were developed for determination of aromatic-, aliphatic- and alkanolamines in aqueous solutions. Isocyanates were determined by reversed-phase liquid chromatography MSMS. HILIC in combination with MS is a most powerful system, and highly sensitive determinations, several orders of magnitude below the OELs, of polar compounds present in the work environment can be accomplished. The selected samplers enable sampling during short sampling times and for whole work shifts. The samplers can be stored for months before and after sampling. The performance of the samplers was unaffected by variation in temperature, humidity, flow-rate and pre- and post-sampling of ambient air. Sampling for the compounds studied is now greatly simplified, and assessment of the work environment is facilitated.<br><p>At the time of the doctoral defence the following papers were unpublished and had a status as follows: Paper 1: Epub ahead of print; Papers 3-5: Manuscripts</p>
31
Ayala, Gerardo. "Synthesis, Structure and Optical Memory Properties of Copper (I) Thiocyanate Networks with Aromatic Amines, Diimines and Alkyl Sulfides." W&M ScholarWorks, 2016. https://scholarworks.wm.edu/etd/1477068031.
Full textAbstract:
A series of CuSCN compounds were synthesized. Ligands included the alkyl sulfides methyl sulfide (Me2S), ethyl sulfide (Et2S), isopropyl sulfide (Pri2S) and tetrahydrothiophene (THT); diimine ligands pyrazine (Pyz), 2,3-dimethylpyrazine (2,3- Me2Pyz), 2,5-dimethylpyrazine (2,5-Me2Pyz), 2-aminopyrazine (2-NH2Pyz) and 2- methoxypyrazine (2-MeOPyz); two-ring diimines quinoxaline (Qox), quinazoline (Qnz), phthalazine (Ptz); and 3-halopyridines 3-chloropyridine (3-ClPy), 3-bromopyridine (3- BrPy), 3-iodopyridine (3-IPy). Crystal structures were solved for twelve products. With the exception of one Cu(II) compound, all could be classified in the common motifs of chains, ladders or sheets. Alkyl sulfides formed either 1:2 (CuSCN)L2 1-D chains (L = Me2S, 1a and THT, 4) or 1:1 (CuSCN)L2 1-D ladders (L = Et2S, 2 and Pri2S, 3) when reacted with CuSCN. New compounds of CuSCN with diimine ligands included two 2:1 (CuSCN)2LL 2-D bridged ladders (LL = Qox, 5 and 2-NH2Pyz, 8), two (CuSCN)L 1:1 2-D sheets (L = Qnz, 6 and 2-MeOPyz, 9) and one 1:1 (CuSCN)LL 2-D sheet (Ptz, 7). Structures of the known 1:2 (CuSCN)L2 compounds, where L = 3-ClPy (15a) or 3-BrPy (16) were solved as 1-D chains. Optical memory experiments sought to rapidly and significantly reduce the peak intensity in the ultraviolet/visible (UV/Vis) emission spectra of the synthesized compounds as a means of storing binary information. Fully emissive states were assigned as “unwritten,” while states with reduced emission were assigned as “written.” Samples were exposed to a high-energy tunable UV laser at 80 K for five minute intervals in order to affect emission intensities. Recovery capabilities were assessed by warming the samples to 298 K, allowing them to reach thermal equilibrium, and cooling them to 80 K before obtaining final scan. The known compounds (CuSCN)2LL, where LL= 2,3- dimethylpyrazine (2,3-Me2Pyz, 11), 2,5-dimethylpyrazine (2,5-Me2Pyz, 12) demonstrated reduced emission after irradiation, but suffered from fatigue after only one write/read/erase cycle. Compound 16 proved the most promising, displaying both significant emission depletion and complete recovery of initial intensity after three cycles. The x-ray crystal structure of 16 indicates numerous close carbon-bromine and sulfur- bromine interactions. Combined with computational calculations indicating an elongation of the pyridine C-Br bond in the most probable excited state, it is plausible that structural features play a role in the optical memory behavior of this compound.
32
Anand, R. "Synthesis of nitrogen containing heterocycles and acid catalyzed reactions of aromatic amines over medium and large pore zeolites." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2002. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2343.
Full text
33
Scholtka, Bettina, Dana Kühnel, Felicitas Taugner, and Pablo Steinberg. "Inflammation does not precede or accompany the induction of perneoplastic lesions in the colon of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine-fed rats." Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2010/4457/.
Full textAbstract:
Heterocyclic aromatic amines (HCAs) are formed in meat cooked at high temperatures for a long time or over an open flame. In this context 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), the most abundant HCA in cooked meat, has been suggested to be involved in colon and prostate carcinogenesis. In the latter case it has been reported that: (1) roughly 50% of Fischer F344 male rats treated with PhIP develop carcinomas in the ventral prostate lobe at 1 year of age; (2) inflammation precedes prostatic intraepithelial neoplasia in PhIP-fed rats; (3) inflammation specifically occurs in the ventral prostate lobe of PhIP-fed rats. To test whether PhIP by itself leads to inflammation in the colon and whether a human-relevant concentration of PhIP is able to induce preneoplastic lesions in the colon, male F344 rats were fed 0.1 or 100 ppm PhIP for up to 10 months and thereafter the colon tissue was analyzed histochemically. In none of the experimental groups signs of acute or chronic colonic inflammation were observed. 0.1 ppm PhIP leads to the development of hyperplastic and dysplastic lesions in the colon of single animals, but the incidence of these lesions does not reach a statistical significance. In contrast, in rats fed 100 ppm PhIP for 10 months hyperplastic and dysplastic colonic lesions were induced in a statistically significant number of animals. It is concluded that: (1) the induction of preneoplastic lesions in rat colon by PhIP is not preceded or accompanied by an inflammatory process; (2) a human-relevant concentration of PhIP alone is not sufficient to initiate colon carcinogenesis in rats.
34
Richter, Catherine Ann. "Regulation of subcellular localization of the aryl hydrocarbon receptor (AHR)." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcitt?p9988694.
Full text
35
Kidd, La Creis R. "Estimation of exposure to two potent heterocyclic aromatic amines in various human populations and their role in colorectal cancer." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/42653.
Full text
36
Muz, Melis Verfasser], Henner [Akademischer Betreuer] [Hollert, and Werner [Akademischer Betreuer] Brack. "Mutagenicity in surface waters : a comprehensive approach to unravel the role of aromatic amines / Melis Muz ; Henner Hollert, Werner Brack." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1161411941/34.
Full text
37
Muz, Melis [Verfasser], Henner [Akademischer Betreuer] Hollert, and Werner [Akademischer Betreuer] Brack. "Mutagenicity in surface waters : a comprehensive approach to unravel the role of aromatic amines / Melis Muz ; Henner Hollert, Werner Brack." Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1161411941/34.
Full text
38
Bellamri, Medjda. "Activation métabolique et génotoxicité des Amines Hétérocycliques Aromatiques (AHA) chez l’Homme." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1B033/document.
Full textAbstract:
Les amines hétérocycliques aromatiques (AHA) sont des contaminants de l'environnement et de l'alimentation, majoritairement formés lors de la cuisson de viande et poisson ainsi que dans la fumée de cigarette et les gaz d'échappements. Les AHA sont mutagènes chez la bactérie, cancérogènes multi-sites chez le rongeur et sont classées comme cancérogènes possibles ou probables chez l'Homme par l'IARC. Il est aujourd'hui indispensable de caractériser des biomarqueurs d'exposition dérivés des AHA (adduits à l'ADN et métabolites) pour améliorer l'estimation du risque chez l'Homme. Des résultats de l'équipe ont démontré que le 2-amino-9H-pyrido[2,3-b]indole (AαC) forme des niveaux d'adduits à l'ADN élevés dans les hépatocytes humains. Ces niveaux sont plus élevés que ceux formés par les autres AHA. L'objectif de cette thèse est de mieux comprendre le potentiel génotoxique d'AαC chez l'Homme. Nos travaux ont démontré que les adduits à l'ADN dérivés d'AαC sont persistants dans les hépatocytes humains et formés à des doses aussi faibles que 1nM. De plus, le CYP1A2 a été confirmé comme enzyme majoritaire dans la bioactivation d'AαC dans le foie humain. Nous avons également caractérisé les métabolites majeurs dérivés d'AαC dans les hépatocytes humains. Cette étude a permis d'établir pour la première fois une corrélation entre l'activité catalytique du CYP1A2, la formation d'AαC-HN2-O-Gl et la formation des adduits à l'ADN dérivés d'AαC. Le métabolite AαC-HN2-O-Gl étant réactif vis-à-vis de l'ADN in vitro, nos travaux confortent l'hypothèse que la voie des UDP-Glucuronosyltransférases (UGTs) est une nouvelle voie de bioactivation d'AαC dans le foie humain. De plus, nous avons montré que les adduits à l'ADN dérivés des AHA sont formés dans les lymphocytes T humains activés et en particulier les adduits en position C8 de la guanine dérivés d'AαC. Au total, ces travaux ont permis l'identification de métabolites stables et des adduits à l'ADN, potentiels biomarqueurs d'exposition à AαC, qui sont indispensables pour une meilleure estimation du risque génotoxique d'AαC chez l'Homme<br>Heterocyclic aromatic amines (HAA) are environmental and food contaminants, mainly formed during meat and fish cooking, but also in cigarette smoke and exhaust gaz. HAA are mutagenic in bacteria, carcinogenic in rodents and are classified as possible or probable human carcinogens by IARC. Today it is essential to characterize exposure biomarkers i.e. DNA adducts and metabolites, to assess the human risk associated with HAA. The research team has previously demonstrated that 2-amino-9H-pyrido[2,3-b]indole (AαC) form high levels of DNA adducts in human hepatocytes. These levels are greater that those derived from other HAAs. Thus, the aim of this thesis was to better understand the genotoxic potential of AαC in human. We demonstrated that in human hepatocytes, DNA adducts derived from AαC are persistent and formed at doses as low as 1nM. Moreover, we confirmed that CYP1A2 is the major enzyme implicated in the bioactivation of AαC in human liver. We have also characterized the major metabolites derived from AαC formed in human hepatocytes. This study allows, for the first time, the establishment of a correlation between the catalytic activity of CYP1A2, AαC-HN2-O-Gl formation and AαC derived DNA adducts formation. AαC-HN2-O-Gl being reactive toward DNA in vitro, our work reinforces the hypothesis that the UDP-glucuronosyltransferase (UGTs) pathway is a new bioactivation pathway for AαC in human liver. Moreover, we demonstrated the formation of HAA derived DNA adducts, especially those derived from AαC at position C8 of guanine, in activated human T lymphocytes. Taken together, our data lead to the identification of stable metabolites as well as DNA adducts which are potentials AαC exposure biomarkers in human. These biomarkers are essential for a better assessment of the genotoxic risk of AαC in human
39
Olivares, Martinez Christopher Ignacio. "Environmental Fate, (Bio)transformation, and Toxicology of 2,4-dinitroanisole (DNAN) in Soils and Wastewater Sludge." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/596139.
Full textAbstract:
Insensitive munition compounds (IMC) are an emerging class of explosives that are less susceptible to accidental explosions compared to the conventional explosives they will be replacing. An IMC that has been incorporated in several explosives formulations is 2,4-dinitroanisole (DNAN). As the manufacture, storage, and use of these compounds increases, the expected releases in natural and engineered systems might pose an environmental hazard to public health and ecosystems. To date there is little information on the environmental fate and toxicology of DNAN. However, nitroaromatic compounds are known to be toxic, mutagenic and difficult to completely biodegrade. In order to study the fate and (bio)transformation of DNAN, microcosm studies with soils and anaerobic wastewater sludge were performed to determine (bio)transformation pathways and key factors influencing (bio)conversion. Transformation was enhanced in anaerobic conditions, in particular when exogenous electron donor was added. Abiotic transformation (in heat-killed soil) was also significant and dominated transformation reactions in soils that were not amended with exogenous electron donor. The organic carbon content of soils was a key factor that correlated to the anaerobic biotransformation rate. Having identified (bio)transformation products using liquid chromatography coupled to quadrupole time-of-flight mass spectrometry, an overall pathway of (bio)transformation was devised and consistent with nitro-group reduction to form aromatic amines. During the nitro-group reduction, reactive products (e.g. nitroso-intermediates) coupled with amines to form azo-dimers and oligomers. Subsequent transformation pathways included N-alkylation, N-acetylation, and stepwise demethoxylation of these oligomers. The assessment of the toxicity of DNAN and its (bio)transformation products was performed utilizing microbial toxicity assays and ecotoxicity evaluation with zebrafish (Danio rerio) embryos. Overall DNAN severely inhibited methanogens (IC₅₀ = 41 μM ), the bioluminescent marine bacterium Aliivibrio fischeri utilized in the Microtox test (IC₅₀ = 57 μM), and nitrifiers (IC₅₀ = 49 μM). Reduced aromatic amine products in general were less toxic than DNAN with the exception of 2-methoxy-5-nitroaniline and 3-nitro-4-methoxyaniline, which were similar in toxicity to some of the test organisms as DNAN. Azo-oligomer surrogates were as toxic or more toxic than DNAN, although at trace levels they significantly stimulated activity. N-acetylated amines were found to have by far the lowest toxicity to microorganisms. In zebrafish embryos, the (bio)transformation product or surrogates 3-nitro-4-methoxyaniline and 2,2'-dimethoxy-4,4'-azodianiline caused developmental abnormalities (each with lowest observable effect level of 6.4 μM). An integrated approach which monitored (bio)transformation product mixture profile in parallel with their toxicity to microbial and zebrafish toxicity was used to characterize toxicity during the time course of the anaerobic (bio)transformation of DNAN. Enhanced inhibition of methanogenic activity and zebrafish mortality were associated with the onset of dimer formation indicating they were being mostly impacted by reactive intermediates formed early in the biotransformation of DNAN. Further accumulation of oligomers was associated with a decrease toxicity. On the other hand, A. fischeri bioluminescence became more and more inhibited as the oligomers formed, indicating different responses depending on target organism. Taken globally, the results indicate that DNAN can be readily transformed in soils and wastewater sludge forming both highly toxic (e.g. azo-oligomers) and non-toxic intermediates (e.g. N-acetylated 2,4-diaminoanisole). Depending on target organism, the prolonged formation of oligomer mixtures either resulted in detoxification or recovery of activity.
40
Mothibedi, Kediemetse (Kedimetse). "A study of electrospun nanofibers and diatomaceous earth materials for the extraction of alkaloids, flavonoids and aromatic amines in various matrices." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1003052.
Full textAbstract:
The thesis explored the use of different sorbent materials in solid phase extraction method development. The methods included the use of the polymeric Agilent Bond Elut Plexa solid phase extraction and electrospun polymer-silica composite sorbents for clean-up and preconcentration. Sample clean-up for alkaloids (hydrastine and berberine) in goldenseal, Hydrastis canadensis and flavonoids (quercetin, kaempferol and isorhamnetin) in Ginkgo biloba was achieved using Bond Elut Plexa SPE sorbent. Clean-up of flavonoids in Ginkgo biloba was also achieved using electrospun polymer-silica composite (polystyrene-silica, polyacrylonitrile-silica and nylon 6-silica) sorbents. All analysis of flavonoids and alkaloids was carried out using an Agilent 1200 Series HPLC coupled with a diode array detector. Good peak separation was achieved in less than 6 min employing an Agilent ZORBAX Eclipse Plus C18 column (4.6 x 75 mm, 3.5 μm) at 35⁰C. The mobile phases employed were 0.1% phosphoric acid/methanol gradient and 0.5% phosphoric acid/methanol (40:60) for alkaloids and flavonoids respectively. The calibration curves exhibited linearity up to 120 μg mL⁻¹ with correlation coefficients of more than 0.9980. The recoveries ranged from 73-109% with relative standard deviation of less than 5% for all analytes. Agilent Chem Elut supported liquid extraction was employed for the development of a sample preparation method for the determination of 24 banned aromatic amines from azo dyes in textile following the EU standard method EN 14362-1:2003 (E) and the Chinese standard method GB/T 17592-2006. The supported liquid extraction was effective in the extraction of the aromatic amines from textile (cotton, wool and polyester/cotton [80%:20%]). Most of the recoveries obtained were conforming to the minimum requirements set in the EN 14362-1:2003 (E) standard method and the relative standard deviations were less than 15%. Good peak separation was obtained within 70 min run time using the Agilent Zorbax SB-Phenyl column (4.6 mm x 250 mm, 5-micron) or the Agilent DB-35 MS (J & W) (30 m x 0.25 mm, 0.25 μm film thickness. It was demonstrated that the polymeric Agilent Bond Elut Plexa, electrospun nanofibers and diatomaceous earth were effective in extraction of alkaloids, flavonoids and aromatic amines in different matrices. The developed methods were simple, rapid and reproducible.
41
Lamani-Dixon, Xolelwa [Verfasser], and Torsten Claus [Akademischer Betreuer] Schmidt. "Analysis of aromatic amines in human urine using comprehensive multi-dimensional gas chromatography mass spectrometry / Xolelwa Lamani-Dixon ; Betreuer: Torsten Claus Schmidt." Duisburg, 2018. http://d-nb.info/1173616055/34.
Full text
42
Al-Zoughool, Mustafa Hussein. "N-Glucuronidation of 4-Aminobiphenyl and the Risk of Urinary Bladder Cancer: Gender Differences." Cincinnati, Ohio : University of Cincinnati, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1115852691.
Full textAbstract:
Thesis (Ph. D.)--University of Cincinnati, 2005.<br>Title from electronic thesis title page (viewed Oct. 3, 2006). Includes abstract. Keywords: 4-Aminobiphenyl, Bladder cancer, Aromatic amines, N-glucuronidation, DNA-adducts. Includes bibliographical references.
43
Klassen, Aline. "Desenvolvimento de métodos para determinação de aminas aromáticas em amostras têxteis por eletroforese capilar." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-15052012-082629/.
Full textAbstract:
Os corantes que apresentam grupos cromóforos do tipo azo (N=N) são amplamente empregados em numerosas aplicações na indústria, para colorir vários bens de consumo, dentre eles os têxteis. Entretanto, pelo fato de formarem aminas aromáticas carcinogênicas, quando a ligação N=N é rompida, seu uso está sujeito à legislação. Levando em consideração o potencial carcinogênico das aminas aromáticas, a quantificação das mesmas em produtos destinados à exportação se faz necessária. A técnica padrão para o monitoramento da presença dessas aminas em bens de consumo como os têxteis é a cromatografia líquida de alta eficiência, entretanto como alternativa tem-se a eletroforese capilar. Assim, neste trabalho 20 aminas aromáticas oriundas de azo corantes, banidas pela Comunidade Européia por meio da Diretiva 2002/61/EC, foram separadas por meio de eletroforese capilar (CE), com detecção no UV-Vis, e, a confirmação da presença dessas aminas em matrizes têxteis foi realizada por um método confirmatório de LC-MS, adaptado da literatura. Em CE o conhecimento das constantes de dissociação ácido-base se faz necessário para a otimização do pH ideal de corrida, assim estas, bem como mobilidades iônicas para cada uma das aminas aromáticas foram determinadas por meio de curvas de mobilidade efetiva em função do pH. O pH ótimo de separação de 2,50 foi determinado por meio do simulador de separação desenvolvido no grupo (SIMLACE). Dos métodos de separação estudados, o que apresentou maior número de aminas separadas (16 aminas) em linha de base em menor tempo (12 min) foi empregando um BGE composto apenas de 70 mmol/L de dihidrogenofosfato de sódio ajustado a pH 2,50 com ácido fosfórico, considerando um condicionamento de capilar de início de trabalho de 10 minutos de flush com BGE (dihidrogenofosfato de sódio 70 mmol/L ajustado a pH 2,50 com ácido fosfórico, contendo trietilamina 12,3 mmol/L) a uma pressão de 950 mbar, seguido da aplicação de uma tensão de +30 kV por 10 minutos; e um condicionamento entre réplicas de corrida eletroforética de 1 minuto de HCl 0,1mol/L (950 mbar) seguidos de 1 minuto de H2O (950 mbar). A extração das aminas da matriz têxtil envolve três etapas: a redução da ligação N=N, extração das aminas formadas e um posterior clean up e pre-concentração, sendo que para este último o sistema que apresentou melhor resposta em termos de eficiência de extração (da ordem de 100%) foi com o uso de extração em fase sólida com resina de troca catiônica. Por outro lado, a extração das aminas 1, 7 e 8 da matriz têxtil foi obtida por ultrassom após o estudo de um planejamento fatorial de superfície de resposta, a uma temperatura de 52 ºC, tempo de ultrassom de 5 minutos e concentração de HCl de 0,77 mol/L, com recuperações de 105 a 115%. Como figuras de mérito do método otimizado tem-se: linearidade no intervalo de 50,11 409,1 mmol/L (R2 > 0,98), LD (2,43 6,70 mmol/L) e LQ (8,10 22,3 mmol/L), precisão (0,23 27,6%), robustez (por planejamento fatorial), seletividade, especificidade (estudos de estresse com extrato da amostra) e recuperação (valores acima). O método validado foi aplicado a sete amostras adquiridas no mercado local. Dentre elas, duas apresentaram picos com tempos de migração e espectros semelhantes às aminas 5, 7 e 15, sendo que as aminas 7 e 15 foram confirmadas por meio do método de LC-MS/MS adaptado da literatura o qual permitiu a caracterização dessas aminas nas matrizes têxteis analisadas.<br>The dyes which have chromophoric groups like azo (N = N) are widely used in numerous applications in industry to color various consumer goods, including textiles. However, because of carcinogenic aromatic amines formed when N=N bond is broken, its use is subject to the legislation. Considering the carcinogenic potential of aromatic amines, to quantify them in products intended for export, is needed. The standard technique for monitoring the presence of these amines in consumer goods such as textiles is a high performance liquid chromatography, however the capillary electrophoresis technique can be a good alternative. In this work 20 aromatic amines derived from azo dyes, banned by the European Community by Directive 2002/61/EC, were separated by capillary electrophoresis (CE) with UV-Vis detection, and confirmation of the presence these amines textile matrix was conducted by a method confirmatory LC-MS, adapted from the literature. The knowledge of the dissociation constant acid-base (pKa) in CE technique is necessary to obtain the optimum pH for the separation. In these way the pKa as well as the ionic mobilities for each aromatic amines were determined by curves of effective mobility as a function of pH. The optimum pH for the separation was 2.50 as determined by the simulator separation developed in the group (SIMLACE). About the separation methods studied, which had a higher number of separate amines (16 amines) in the baseline in a shorter time (12 min) employing a BGE composed only of 70 mmol/L sodium dihydrogen phosphate adjusted to pH 2.50 with phosphoric acid, with a conditioning capillary either at the beginning of the working day (10 minutes flush with BGE (sodium dihydrogen 70 mmol/L adjusted to pH 2.50 with phosphoric acid, triethylamine containing 12.3 mmol/L) at a pressure 950 mbar followed by applying a voltage of +30 kV for 10 minutes) and among replicas (1 minute of HCl 0.1 mol/L (950 mbar) followed by 1 minute of H2O (950 mbar)). The extraction of amines textile matrix involves three steps: reduction of N = N bond, extraction of the amines formed and a subsequent clean up and pre-concentration. About the latter step, the best response in terms of extraction efficiency (about 100%) was obtained using solid phase extraction (SPE) with cationic exchange resin. In addition, the best condition for ultrasound extraction of the amines 1, 7 and 8, was determined by means of a response surface factorial design with three variables and two levels. The optimum condition was: temperature of 52 °C, application of ultrasound for 5 min and HCl concentration of 0.77 mol/L, with recoveries of 105% to 115%. Figures of merit for optimized method include: linearity in the range from 50.11 to 409.1 mmol/L (R2> 0.98), LD (limit of detection, 2.43 to 6.70 mmol/L) and LQ (limit of quantification, 8.10 to 22.3 mmol/L), precision (0.23 to 27.6%), robustness (established by a factorial design), selectivity, specificity (stress studies with real sample extracts) and recovery (listed above). The validated method was applied to seven samples purchased at local markets. Among them, two presented peaks with migration times and spectra similar the amines 5, 7, 12 and 15. But, in only one sample the amines 7 and 15 were confirmed by LC-MS/MS.
44
Fedotova, Alena. "Amines aromatiques stériquement encombrées dans la réaction d'aza-Michael : effets de solvant et haute pression." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMR056/document.
Full textAbstract:
Au cours de cette thèse, nous avons rapporté que la combinaison unique de l'hexafluoroisopropanol (HFIP), utilisé comme solvant, et des conditions hyperbares (10-15 kbar) permet une addition sans précédent de nucléophiles-1,4 pauvres, comme les amines aromatiques, sur des récepteurs Michael encombrés, sans promoteur externe. De plus, l'addition d'hétéro-Michael d'anilines fonctionnellement substituées sur des esters insaturés-α,β est définie par la différence d'acidité entre le solvant et l'amine. La réaction avec des anilines plus basiques se déroule facilement dans le méthanol. En revanche, les solvants protiques très polaires comme les alcools fluorés (HFIP et TFE) favorisent l'addition d'aza-Michael de nucléophiles plus faibles. Enfin, une méthode verte et sans catalyseur de construction de nouveaux dérivés d'acides aminés contenant des fragments d'adamantane et d'aziridine a été développée. Et il est prouvé que la réaction d'aza-Michael initie la formation de l’hétérocycle<br>Along this PhD work, we have reported that the unique combination of hexafluoroisopropanol (HFIP), employed as solvent, and hyperbaric conditions (10-15 kbar) allows unprecedented 1,4-addition of poor nucleophiles such as aromatic amines onto sluggish (cumbersome) Michael acceptors without any promoter nor work-up. Moreover, The hetero-Michael addition of functionally substituted anilines to α,β-unsaturated esters is significantly defined by the difference of acidity between the solvent and the amine. Reaction with more basic anilines proceeds smoothly in methanol. In contrast, very polar protic solvent such as fluorinated alcohols (HFIP and TFE) favor the aza-Michael addition of more weak nucleophiles. Finally, green and catalyst-free method of new amino acid derivatives construction containing adamantane and aziridine fragments was developed. And it is proved that aza-Michael reaction initiates the formation of heterocycle
45
Fuchs, Iris Judith. "Untersuchungen zur chemischen Transformation von intestinalen Epithelzellen der Ratte und des Menschen durch 2-Hydroxyamino-1-methyl-6-phenylimidazo(4,5-b)pyridin." Phd thesis, Universität Potsdam, 2006. http://opus.kobv.de/ubp/volltexte/2007/1180/.
Full text
46
Lavigne, André. "Oxydations cupro-catalysees des amines aliphatiques : etudes mecanistiques et applications synthetiques." Paris 6, 1987. http://www.theses.fr/1987PA066470.
Full textAbstract:
Preparation de nitriles a partir d'amines primaires et d'alpha -aminoacides. Les acides amines monosubstutitues rch(nh::(2))co::(2)h donnent le nitrile rcn, alors que les acides amines disubstitues rr'c(nh::(2))co::(2)h conduisent a l'azine rr'c=n-n=cr'r. Les mecanismes proposes font intervenir le cuivre (iii), forme in situ a partir du cuivre (i) et de l'oxygene
47
Wiedemann, Elija Nathan [Verfasser], та Armin [Akademischer Betreuer] Ofial. "Aliphatic and aromatic amines : C-H bond functionalization and kinetics of their reactions with β-lactones, β-lactams, and carbocationic electrophiles / Elija Nathan Wiedemann ; Betreuer: Armin Ofial". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/1199816663/34.
Full text
48
Mora, Anne-Sophie. "Élaboration de revêtements époxy pour contact alimentaire à empreinte environnementale réduite A perspective approach on the amine reactivity and the hydrogen bonds effect on epoxy-amine systems vanillin-derived amines for bio-based thermosets synthesis of biobased reactive hydroxyl amines by amination reaction of cardanol-based epoxy monomers synthesis of pluri-functional amine hardeners from bio-based aromatic aldehydes for epoxy amine thermosets cardanol-based epoxy monomers for high thermal properties thermosets." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2019. http://www.theses.fr/2019ENCM0012.
Full textAbstract:
Les travaux de thèse présentés sont issus d’une collaboration industrielle avec la société Nouvelle Sogatra, spécialisée dans la conception, la fabrication et la commercialisation de revêtements de protection bi-composants répondant aux normes d’alimentarité. L’objectif principal de ce projet est de proposer de nouveaux revêtements époxydiques performants en utilisant des produits biosourcés et, dans l’idéal, moins dangereux pour l’Homme et pour l’environnement. Ces travaux de thèse s’axent autour de l’identification de nouvelles méthodologies de synthèse de durcisseurs aminés biosourcés qui soient facilement applicables industriellement.L’amination directe des groupements époxy par ouverture de cycle en présence d’ammoniaque ainsi que l’amination réductrice via la synthèse d’imine ont été sélectionnées comme voies de synthèse pour leur facilité d’application et leur caractère respectueux de l’environnement. Pour cela, des précurseurs commerciaux biosourcés et/ou à toxicité réduite ont été sélectionnés. De nouveaux durcisseurs aminés ont été synthétisés à partir de bio ressources telles que la vanilline, le cardanol et le benzaldéhyde. Ces durcisseurs ont ensuite été utilisés pour la synthèse de système époxy-amine thermodurcissables dont les propriétés physico-chimiques et thermodynamiques ont été caractérisées<br>The presented PhD works were initiated by an industrial collaboration with the company Nouvelle Sogatra, specialized in the design, manufacturing and marketing of two component protective coatings for food contact. The aim of this project is to offer new high-performance epoxy thermosets from bio based reactants and, ideally with a low impact on the health and the environment. This PhD works focus on the identification of new synthesis methodologies of bio-based amine hardeners, which could be easily industrialized.The direct epoxy amination by ring opening using ammonia and the reductive amination via imine synthesis were selected as synthesis routes for their simple utilization and their eco friendly character. Hence, bio based and/or reduced toxicity commercial precursors were selected. New amine hardeners were synthesized from bio resources, such as vanillin, cardanol and benzaldehyde. These hardeners were then used to synthesize epoxy-amine thermosets, whose thermomechanical and physicochemical properties were characterized
49
Cui, Wenge Cui Wenge. "Part 1, Glyoxal-guanine DNA adducts, derivatization, structure, stability and new detection methodology ; Part 2, Nitrosation studies of oxazolines and imidazolines and the synthesis of N-cyclopropyl aromatic amines /." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9998477.
Full text
50
Chequer, Farah Maria Drumond. "Avaliação da capacidade de dano ao material genético pelos azo corantes Disperse Red 1, Disperse Red 13 e Disperse Orange 1: identificação e análise do potencial mutagênico dos seus produtos de biotransformação." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/60/60134/tde-28032012-101528/.
Full textAbstract:
Atualmente, a utilização de azo corantes por vários ramos industriais constitui um problema ambiental e de saúde pública, tendo em vista o lançamento de quantidades elevadas para o meio ambiente e a falta de dados toxicológicos a cerca dos corantes e de seus metabólitos gerados, principalmente, após os processos de oxidação e redução. Nosso grupo realizou ensaios com micronúcleos em linfócitos humanos e em células HepG2 e ensaio de mutagenicidade com Salmonella typhimurium, demonstrando que os azo corantes Disperse Red 1, Disperse Red 13 e Disperse Orange 1 são mutagênicos para os diferentes parâmetros. Dessa forma, neste trabalho foi avaliada a capacidade de ligação dos corantes originais com o DNA e a base nitrogenada guanosina, a fim de elucidar o mecanismo de ação mutagênica. Adicionalmente, foi realizada a análise do potencial mutagênico do corante Disperse Red 1 e de seus metabólitos por meio do teste de mutação gênica em células de linfomas de camundongo (Mouse Lymphoma Assay), e também foram avaliados os produtos de oxidação e redução dos azo corantes Disperse Red 1, Disperse Red 13 e Disperse Orange 1, por meio do teste de mutagenicidade com Salmonella typhimurium. Posteriormente, foi investigada a possível formação de aminas aromáticas e de outros compostos, após os ensaios eletroquímicos e reação com S9, utilizando CLAE/DAD e CG/EM. Nossos resultados mostraram que a formação de adutos com o DNA, especificamente com a base guanosina, não é o mecanismo de ação tóxica preferencial para os azo corantes estudados. O corante Disperse Red 1 e seus produtos de biotransformação apresentaram resultados negativos no teste de mutação gênica em células de linfoma de camundongos. No entanto, tanto os produtos de oxidação como os de redução dos três corantes estudados apresentaram potencial mutagênico ao serem testados no Ensaio Salmonella/microssoma. Os produtos identificados após a oxidação química e enzimática (utilizando S9) e redução química dos três corantes estudados foram: sulfato 2-[(4-aminofenil)etilamino]- etanol monohidratada, 2-cloro-4-nitro-benzamina, benzamina, nitrobenzeno, 4-nitro-benzamina, 2-(etilfenilamino)-etanol, N-fenilbenzamina, N-fenil-1,4-benzenodiamina. Portanto, nossos dados mostram que a exposição por via oral a esses corantes tem relevância toxicológica, visto que podem causar danos à saúde não somente pela exposição aos corantes inalterados, mas também devido à formação de produtos tóxicos após a biotransformação. Cabe ressaltar que os corantes estudados no presente trabalho são amplamente utilizados por indústrias têxteis no Brasil, o que pode levar à contaminação de águas e alimentos.<br>Currently, the use of azo dyes by various industries is an environmental problem and public health, considering the release of large quantities to the environment and the lack of toxicological data about the dyes and their metabolites generated, especially after the processes of oxidation and reduction. Our group carried out micronuclei assay in human lymphocytes and HepG2 cells and mutagenicity test with Salmonella typhimurium, indicating that the azo dyes Disperse Red 1, Disperse Red 13 and Disperse Orange 1 are mutagenic to the different parameters. Thus, this study evaluated the binding capacity of the original dyes with DNA and nitrogenous base guanosine in order to elucidate the mechanism of mutagenic action. Additionally, we performed the analysis of mutagenic potential of Disperse Red 1 dye and its metabolites using Mouse Lymphoma Assay, and also evaluated the products of oxidation and reduction of the azo dyes Disperse Red 1, Disperse Red 13 and Disperse Orange 1, using the mutagenicity test with Salmonella typhimurium. Also it was investigated the possible formation of aromatic amines and other compounds after the electrochemical assays and reaction with S9, using HPLC / DAD and GC / MS. Our results showed that the formation of adducts with DNA, specifically with the guanosine base is not the preferred mechanism of toxic action for the azo dyes studied. The dye Disperse Red 1 and its biotransformation products had negative results in the mouse lymphoma assay. However, both the products of oxidation and the reduction of three dyes studied showed mutagenic potential in the Salmonella/ microsome assay. The products identified after chemical and enzymatic oxidation (using S9) and chemical reduction of three dyes studied were: sulfate 2-[(4- aminophenyl)ethylamino]-Ethanol monohydrate, 2-chloro-4-nitro-benzamine, benzamine, nitrobenzene, 4-nitro-benzamine, 2-(ethylphenylamino)-Ethanol, Nphenyl- benzamine, N-phenyl-1,4-benzenediamine. Therefore, our data show that oral exposure to these dyes have toxicological significance, since it can cause damage to health not only by exposure to dyes unchanged, but also due to the formation of toxic products after the biotransformation. It is noteworthy that the dyes studied in this work are widely used by textile industries in Brazil, which can lead to contamination of food and water.