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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

[en] SYNTHESIS AND CHARACTERIZATION OF COMPLEXES INVOLVING POLYAMINES AND THE METAL IONS ZINC (II), NICKEL (II) AND PALLADIUM (II) / [pt] SÍNTESE E CARACTERIZAÇÃO DE COMPLEXOS ENVOLVENDO POLIAMINAS E OS ÍONS METÁLICOS ZINCO (II), NÍQUEL (II) E PALÁDIO (II)

MARIA STELLA NUNES DE OLIVEIRA 08 October 2010 (has links)
[pt] O presente trabalho descreve a síntese e a caracterização de treze complexos envolvendo as poliamina etilenodiamina, diaminopropano, diaminobutano, espermidina e espermina e os íons metálicos Zn (II), Ni (II) e Pd (II). Todas as sínteses foram realizadas em água, um solvente de importância biológica, e em condições próximas às fisiológicas, com o objetivo de mimetizar as ligações e compreender como ocorre a interação das poliaminas com ânions no ciclo biológico, haja vista que em pH fisiológico essas moléculas se encontram primordialmente na forma protonada e interagem com biomoléculas aniônicas, entre essas, determinados sítios do DNA. Utilizou-se para a caracterização dos complexos as técnicas de condutivimetria, análise elementar, espectrometria de absorção atômica, análise termogravimétrica, espectroscopia no infravermelho, espectroscopia de ressonância magnética nuclear de Hidrogênio e Carbono 13 (para os complexos de zinco), difratometria de Raio-X (para os cristais de zinco), entre outras. Inicialmente foram sintetizados os complexos do tipo (poliamina[ZnCl(4)]) e, posteriormente, compostos análogos de íon níquel (II) de estequiometria (poliamina[NiCl(4)]). Observou-se que nesses complexos, as poliaminas interagem com o ânion tetraclorometalato (II) através de ligações de hidrogênio. Essas interações ocorrem entre o hidrogênio da amina primária e o cloro da esfera de coordenação. Os complexos formados pelo íon metálico paládio (II) apresentaram, conforme as análises realizadas, estruturas químicas distintas dos demais compostos. Neste caso, foram obtidos os complexos [Pd(Cl)(2)(C(2)H(8)N(2))], [Pd(Cl)(2)(C(3)H(10)N(2))] e [Pd(2)(Cl)(4)(C(10)H(27)N(4))], que apresentam importância como possíveis fármacos para o tratamento do câncer. / [en] This paper describes the synthesis and characterization of thirteen complexes involving the polyamines ethylenediamine, diaminopropane, diaminobutane, spermidine and spermine, and the metal ions Zn (II), Ni (II) and Pd (II). All syntheses were performed in water, a solvent of biological importance, and under near-physiological changes in order to mimic the bonds and understand the interaction of polyamines with anions in the biological cycle. At physiological pH these molecules are primarily in the protonated form and interact with anionic molecules, among which certain DNA sites. The complexes were characterized by the techniques of conductivity, elemental analysis, atomic absorption spectrometry, thermogravimetric analysis, infrared spectroscopy, nuclear magnetic resonance of Hydrogen and Carbon 13 (for the zinc complexes), and Xray diffraction (for zinc crystals). The complexes of the type (polyamine [ZnCl4]) were synthesized first and, subsequently, analogous compounds of ion nickel (II) with stoichiometry (polyamine [NiCl4]) were synthesized. It was observed that in these complexes, the polyamines interact with the tetrachlorometalate (II) anion via hydrogen bonds. These interactions occur between the primary amine hydrogen and the chlorine from the coordination sphere. The metal ion complexes formed by palladium (II) showed, as the analysis data, chemical structures distinct from the other compounds. In this case, we obtained the complex [Pd(Cl)(2)(C(2)H(8)N(2))], [Pd(Cl)(2)(C(3)H(10)N(2))] e [Pd(2)(Cl)(4)(C(10)H(27)N(4))], which have importance as potential drugs for the treatment of cancer.
12

Phosphite Ligands Based On The Calix[4]arene Scaffold And Their Palladium, Platinum And Rhodium Complexes

Maji, Pathik 12 1900 (has links) (PDF)
No description available.
13

Síntese de novos compostos acridínicos e mostardas com potencial atividade antitumoral / Synthesis of new acridines and mustards compounds with potential antitumoral activity

Melo, Andréa Lopes 04 December 2015 (has links)
Cancer is a disease that kills the world and it is estimated that in 2030 the incidence of this disease in the world reach 21.4 million new cases with 13.2 million deaths. Due to the resistance, non-selectivity and high cytotoxicity, many of the current drugs produce side effects such as bone marrow depression, sterility, risk of non-lymphocytic leukemia, among others. Thus it is necessary to the development of new anticancer drugs that have less harmful effects. Thus, six new compounds were synthesized, four acridínicos derivative, a derivative of bis (cloroetila) and palladium (II) complex acridínico, whose acronyms, respectively (Acri)2N, AcriPro, ACDMA, ACBr2MAN, (Most)2N and ACDMAPd. All these compounds derived from Schiff base had satisfactory yields and characterized by NMR techniques (1H, 13C, COSY, J solved) spectroscopy in the infrared, mass spectrometry and elemental analysis. The strains used human tumor cells were HT-29 (human colon cancer), MCF-7 (human breast cancer), Hep-2 (human larynx carcinoma), NCI-H292 (carcinoma human pulmonary mucoepidermoid) and HL -60 (acute promyelocytic leukemia) and derivatives AcriPro, ACDMA, (Most)2N and ACDMAPd showed the best results of IC50 for the HL-60 cells. / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O câncer é uma das doenças que mais mata no mundo e estima-se que em 2030 a incidência no mundo desta doença alcance 21,4 milhões de novos casos com 13,2 milhões de mortes. Devido à resistência, a não seletividade e a alta citotoxicidade, grande parte dos fármacos atuais produzem efeitos indesejáveis tais como: depressão na medula óssea, esterilidade, risco de leucemia não linfocítica, entre outros. Desta forma faz-se necessário o desenvolvimento de novos fármacos antitumorais que possuam menos efeitos agressivos. Assim, foram sintetizados seis novos compostos, sendo quatro derivados acridínicos, um derivado bis(cloroetila) e um complexo de paládio(II) acridínico, que tem como acrônimos, respectivamente, (Acri)2N, AcriPro, ACDMA, ACBr2MAN, (Most)2N e ACDMAPd. Todos esses compostos derivados de base de Schiff tiveram rendimentos satisfatórios e foram caracterizados pelas técnicas de RMN (1H, 13C, COSY, J resolvido), espectroscopia na região do infravermelho, espectrometria de massas e Análise Elementar. As linhagens de células tumorais humanas utilizadas foram HT-29 (câncer de cólon humano), MCF-7 (câncer de mama humano), HEp-2 (carcinoma de laringe humana), NCI-H292 (carcinoma mucoepidermoide de pulmão humano) e HL-60 (leucemia promielocitica aguda) e os derivados AcriPro, ACDMA, ACDMAPd e (Most)2N apresentaram os melhores resultados de CI50 para a células HL-60.
14

Macrocicles nitrogenats contenint unitats de ferrocè i llurs complexos de Pal·ladi(0). Estudi estructural i aplicacions en catàlisi

Pla i Quintana, Anna 23 November 2004 (has links)
La present tesi doctoral s'ha basat en la caracterització estructural i en l'estudi de les propietats catalítiques de nous complexos de pal·ladi(0) amb lligands olefínics contenint unitats de ferrocè. En una primera fase s'ha desenvolupat la síntesi d'estructures de tipus (E, E, E)-1,6,11-trisarilsulfonil-1,6,11-triazaciclopentadeca-3,8,13-triè contenint des d'una fins a tres unitats de ferrocè i s'ha estudiat la seva complexació amb pal·ladi(0). Mitjançant estudis electroquímics s'ha avaluat la seva possible aplicació en el reconeixement molecular electroquímic. Encara que aquest tipus d'estructures no han resultat vàlides per aquest tipus de processos de reconeixement, l'estudi electroquímic ha permès determinar que la presència del grup ferrocenil influeix en les propietats redox del metall complexat. S'ha descrit també l'obtenció de macrocicles pentaolefínics anàlegs de 25 membres contenint unitats de ferrocè i s'ha estudiat paral·lelament la seva complexació amb pal·ladi(0).En una segona part del treball s'han avaluat les propietats catalítiques del complex (E, E, E)-6,11-bis[(p-metilfenil)sulfonil]-1-ferrocenilsulfonil-1,6,11-triazaciclopentadeca-3,8,13-trièpal·ladi(0), en reaccions clàssicament catalitzades per pal·ladi tals com l'acoblament creuat de Suzuki o la reacció de Heck, i s'ha pogut determinar que és un catalitzador actiu en aquest tipus de reaccions, essent a més possible, la seva recuperació i reutilització. En el cas concret de la reacció de Heck s'han emprat sals de diazoni com a agents arilants i cal destacar que s'ha descrit el primer sistema catalític recuperable i reutilitzable per aquest tipus de reaccions. Mitjançant espectrometria de masses amb ionització per electrospray ha estat possible determinar el rol mecanístic del nostre complex de pal·ladi en la reacció de Heck amb sals de diazoni.Finalment, en una tercera part estructural del treball s'ha estudiat el comportament espectroscòpic dels complexos de pal·ladi(0) anteriorment mencionats, contenint des de tres unitats aríliques iguals fins a tres unitats aríliques diferents. Mitjançant RMN i difracció de raigs-X s'ha determinat que la complexitat estereoquímica dels complexos deriva dels isòmers que es poden formar mitjançant complexació del metall amb cada una de les cares dels tres dobles enllaços continguts a l'estructura. / The present work has been directed towards the structural characterization and the catalytic activity evaluation of new olefinic macrocyclic palladium(0) complexes containing ferrocene units.The synthesis of 15-membered macrocycles, namely (E, E, E)-1,6,11-trisarylsulfonyl-1,6,11-triazacyclopentadeca-3,8,13-triene, containing from one to three ferrocenyl units has been described and its complexation ability towards palladium(0) has been demonstrated. By studying the electrochemical behaviour of the synthesized macrocyclic ligands and their palladium(0) complexes, it has been shown that they do not have application in electrochemical recognition of palladium(0). This electrochemical study has evidenced, though, that the ferrocenyl group is strongly influencing the palladium redox properties. The synthesis of analogous 25-membered pentaolefinic macrocycles containing ferrocene has also been described. Furthermore, a palladium(0) complex of this 25-membered macrocycle has been isolated and characterized by NMR and electrospray ionization mass spectrometry.On the other hand, the catalytic activity of the palladium(0) complex (E, E, E)-6,11-bis[(p-methylphenyl)sulfonyl]-1-ferrocenylsulfonyl-1,6,11-triazacyclopentadeca-3,8,13-trienepalladium(0), has been studied. Our catalyst has shown to be active in Suzuki type cross-couplings and in the Heck reaction, and furthermore, its recovery and reuse has proved to be feasible. Of great importance is the fact that our palladium-triolefinic macrocyclic complex is the first recoverable catalyst described in Heck reaction with arenediazonium cations. Electrospray ionization mass spectrometry has been used as the tool for investigating the mechanistic role of the palladium(0) complex in the Heck reaction.Finally, the spectroscopic behaviour of the formerly mentioned triolefinic palladium(0) complexes containing from one to three aryl units has been studied. By means of NMR and X-ray diffraction, it has been proved that the stereochemical complexity is connected to the different isomers that can be formed by complexation of the metal to one or the other face of each of the three olefins involved.

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