No / A novel series of 1,4-disubstituted chloroethylaminoanthraquinones, containing alkylating chloroethylamino functionalities as part of a rigid piperidinyl or pyrrolidinyl ring-system, have been prepared. The target compounds were prepared by ipso-displacement of halides of various anthraquinone chromophores by either hydroxylated or chlorinated piperidinyl- or pyrrolidinyl-alkylamino side chains. The chloroethylaminoanthraquinones were shown to alkylate guanine residues of linearized pBR322 (1¿20 ¿M), and two symmetrically 1,4-disubstituted anthraquinones (compounds 14 and 15) were shown to interstrand cross-link DNA in the low nM range. Several 1,4-disubstituted chloroethylaminoanthraquinones were potently cytotoxic (IC50 values: ¿40 nM) in human ovarian cancer A2780 cells. Two agents (compounds 18 and 19) exhibited mean GI50 values of 96 nM and 182 nM, respectively, in the NCI human tumor cell line panel. Derivatization of the potent DNA cross-linking agent 15 to an N-oxide resulted in loss of the DNA unwinding, DNA interstrand cross-linking and cytotoxic activity of the parent molecule.

Fundação de Amparo a Pesquisa do Estado de Minas Gerais / Platinum compounds, such as cisplatin, oxaloplatin and carboplatin, have been used as chemotherapeutic agents for the treatment of various types of cancer. Several other complexes of this metallic ion are also under clinical evaluation. However, the utilization of platinum compounds as antitumor agents is associated with many severe effects and cellular resistance has also been observed. Therefore, many research groups have been working to synthesize new platinum complexes that are more efficient and show fewer undesired effects associated with their use in medicine. Thus in this work, six new complexes of platinum and palladium were isolated with 4- nitrobenzoic hydrazide(4-NH), acid 2-furoic hydrazide(FH) and 2,4- dinitrophenylhydrazine(2,4-DNPH). These complexes were characterized by spectroscopic techniques and the results have shown that the ligands are coordinated to platinum or palladium by the basic nitrogen of NH2 group and have the general formula [M(L)2X2].nH2O where M= Pt2+ or Pd2+, X = Cl- or I- and n = 0 or 1. Infrared Analyses were made in the region of 400 - 4000 cm-1, except the complex with the ligand 2,4 - dinitrophenylhydrazine which began in the range of 200 cm-1. In addition, UV spectroscopy was performed on-visible range of 200-800 nm. The thermal stability of the complexes containing acid 2-furoic hydrazide and 2, 4-dinitrophenylhydrazine was analyzed in the temperature range 25 900 ºC. The antitumor activity of the synthesized compounds has been studied. The compound [Pt(4-NH)2I2], was found to display cytotoxicity (IC50 = 0.96 μmol/L) against K562 tumoral cell line and, when compared to cisplatin, it was five times more active. / Alguns compostos de platina(II), como por exemplo, a cisplatina, a oxaloplatina e a carboplatina, têm sido utilizados como agentes quimioterápicos no tratamento de alguns tipos de câncer, sendo que vários outros complexos deste íon metálico encontram-se em fase de testes clínicos. Entretanto, estes fármacos apresentam diversos efeitos colaterais severos e, além disso, tem sido observado o aparecimento de resistência celular. Nesse sentido, vários grupos de pesquisa têm buscado a síntese de novos complexos de platina que sejam mais eficazes e que apresentem uma diminuição dos efeitos indesejáveis associados à utilização destes na medicina. Assim, neste trabalho seis novos complexos de platina(II) e paládio(II) foram isolados com os ligantes 4-nitrobenzóico hidrazida(4-NH), ácido 2-furóico hidrazida(FH) e 2,4 dinitrofenilhidrazina(2,4-DNPH). Esses complexos foram caracterizados por técnicas espectroscópicas e, os resultados mostram que os ligantes estão coordenados ao íon platina ou paládio via nitrogênio (NH2) e possuem a fórmula geral [M(L)2X2].nH2O, em que M= Pt2+ ou Pd2+, X = Cl- ou I- e n = 0 ou 1. As analises de infravermelho foram feitas na região de 400- 4000 cm-1, salvo os complexos com o ligante 2,4- dinitrofenilhidrazina que começaram na faixa de 200 cm-1. Além disso, a espectroscopia na região do UV-visível foi feita na faixa de 200-800 nm. A estabilidade térmica dos complexos contendo os ligantes ácido 2-furóico hidrazida e 2,4- dinitrofenilhidrazina foi avaliada no intervalo de temperatura compreendido entre 25- 900°C. A atividade antitumoral dos compostos sintetizados foi estudada contra a linhagem celular tumoral K562. O composto [Pt(4-NH)2I2] exibe uma ótima atividade antiproliferativa (IC50 = 0,96 μmol/L) e, se comparado à cisplatina, é cerca de cinco vezes mais ativo. / Mestre em Química

Yes / A range of oxobis(phenyl‐1,3‐butanedione) vanadium(IV) complexes have been successfully synthesized from cheap starting materials and a simple and solvent‐free one‐pot dry‐melt reaction. This direct, straightforward, fast and alternative approach to inorganic synthesis has the potential for a wide range of applications. Analytical studies confirm their successful synthesis, purity and solid‐state coordination, and we report the complexes’ uses as potential drug candidates for the treatment of cancer. After a 24‐hour incubation of A549 lung carcinoma cells with the compounds, they reveal cytotoxicity values 11‐fold greater than cisplatin, and remain non‐toxic towards normal cell types. Additionally, the complexes are stable over a range of physiological pH values and show the potential for interactions with BSA. / University of Bradford. Grant Number: Internal Research Development Fund

Estudos sobre a inserção de complexos oxindolimínicos de cobre(II) ou zinco(II) em argilas sintéticas beidelitas foram desenvolvidos visando obter carregadores inorgânicos capazes de promover a liberação modificada de metalofármacos. Investigações anteriores mostraram que os complexos estudados são promissores agentes antitumorais. São capazes de se ligar ao DNA, nas alças menor ou maior dependendo do ligante, causando danos oxidativos através da formação de espécies reativas de oxigênio (EROs), especialmente radicais hidroxil, no caso de complexos de cobre, que apresentam atividade redox. Também interagem com mitocôndrias levando a uma diminuição do potencial de membrana e atuando como agentes desacopladores. Constituem assim compostos indutores de apoptose ou morte celular programada. Adicionalmente inibem proteínas envolvidas no ciclo celular, como topoisomerase I humana e quinases dependentes de ciclina (CDK1 e CDK2). As beidelitas foram sintetizadas e caracterizadas por métodos já descritos na literatura. Posteriormente, em presença dos complexos, formaram materiais híbridos do tipo beidellita/[complexo]. A caracterização das argilas e dos materiais híbridos obtidos foi realizada usando diferentes técnicas: espectroscopias UV/Vis, IV e EPR, análise termogravimétrica, difratometria de raios X. Na caracterização dos complexos utilizou-se ainda espectrometria de massas (ESI-MS). Os materiais híbridos preparados mostraram-se estáveis e capazes de inviabilizar células tumorais (HeLa), no caso dos materiais híbridos com compostos de cobre(II), com IC50 na faixa de 0,11 a 0,41 mg/mL. Ao contrário, os compostos análogos de zinco(II) e as argilas puras mostraram-se não-tóxicas frente às mesmas células. Os resultados obtidos indicam uma promissora possibilidade de uso das beidellitas como carregadores destes complexos metálicos. / Studies on the insertion of oxindolimine complexes of copper(II) or zinc(II) in synthetic beidellites clays have been developed to obtain an inorganic support capable of promoting the modified-release of metallopharmaceuticals. Previous investigations have shown that the studied complexes are promising antitumor agents. They are able to bind to DNA, in the minor or major groves, causing oxidative damage via formation of reactive oxygen species (ROS), especially hydroxyl radicals, in the case of copper complexes, which have redox properties. They also interact with mitochondria leading to a decrease of membrane potential and acting as decoupling agent. Thus, these compounds can induce apoptosis or programmed cell death. Additionally, they inhibit proteins involved in the cell cycle, such as human topoisomerase I and cyclin dependent kinases (CDK1 and CDK2). The beidellites were synthesized and characterized by methods described in the literature. Additionally, in the presence of these complexes were obtained hybrid materials type beidellita/[complex]. The characterization of clays and the obtained hybrid materials were performed using different techniques: spectroscopy UV/Vis, IR and EPR, thermogravimetric analysis, X-ray powder diffraction. In the characterization of the complexes mass spectrometry (ESI-MS) was also used. The prepared hybrid materials were stable and able to derail tumor cells (HeLa) in the case of hybrid materials with copper(II) compounds, with IC50 in the range from 0.11 to 0.41 mg/mL. Unlikely, the analogous compounds of zinc(II) and pure clays have proved to be non-toxic facing the same cells. These results indicate a promising possibility of using the beidellites as carriers of these antitumor metal complexes

Estudos sobre a inserção de complexos oxindolimínicos de cobre(II) ou zinco(II) em argilas sintéticas beidelitas foram desenvolvidos visando obter carregadores inorgânicos capazes de promover a liberação modificada de metalofármacos. Investigações anteriores mostraram que os complexos estudados são promissores agentes antitumorais. São capazes de se ligar ao DNA, nas alças menor ou maior dependendo do ligante, causando danos oxidativos através da formação de espécies reativas de oxigênio (EROs), especialmente radicais hidroxil, no caso de complexos de cobre, que apresentam atividade redox. Também interagem com mitocôndrias levando a uma diminuição do potencial de membrana e atuando como agentes desacopladores. Constituem assim compostos indutores de apoptose ou morte celular programada. Adicionalmente inibem proteínas envolvidas no ciclo celular, como topoisomerase I humana e quinases dependentes de ciclina (CDK1 e CDK2). As beidelitas foram sintetizadas e caracterizadas por métodos já descritos na literatura. Posteriormente, em presença dos complexos, formaram materiais híbridos do tipo beidellita/[complexo]. A caracterização das argilas e dos materiais híbridos obtidos foi realizada usando diferentes técnicas: espectroscopias UV/Vis, IV e EPR, análise termogravimétrica, difratometria de raios X. Na caracterização dos complexos utilizou-se ainda espectrometria de massas (ESI-MS). Os materiais híbridos preparados mostraram-se estáveis e capazes de inviabilizar células tumorais (HeLa), no caso dos materiais híbridos com compostos de cobre(II), com IC50 na faixa de 0,11 a 0,41 mg/mL. Ao contrário, os compostos análogos de zinco(II) e as argilas puras mostraram-se não-tóxicas frente às mesmas células. Os resultados obtidos indicam uma promissora possibilidade de uso das beidellitas como carregadores destes complexos metálicos. / Studies on the insertion of oxindolimine complexes of copper(II) or zinc(II) in synthetic beidellites clays have been developed to obtain an inorganic support capable of promoting the modified-release of metallopharmaceuticals. Previous investigations have shown that the studied complexes are promising antitumor agents. They are able to bind to DNA, in the minor or major groves, causing oxidative damage via formation of reactive oxygen species (ROS), especially hydroxyl radicals, in the case of copper complexes, which have redox properties. They also interact with mitochondria leading to a decrease of membrane potential and acting as decoupling agent. Thus, these compounds can induce apoptosis or programmed cell death. Additionally, they inhibit proteins involved in the cell cycle, such as human topoisomerase I and cyclin dependent kinases (CDK1 and CDK2). The beidellites were synthesized and characterized by methods described in the literature. Additionally, in the presence of these complexes were obtained hybrid materials type beidellita/[complex]. The characterization of clays and the obtained hybrid materials were performed using different techniques: spectroscopy UV/Vis, IR and EPR, thermogravimetric analysis, X-ray powder diffraction. In the characterization of the complexes mass spectrometry (ESI-MS) was also used. The prepared hybrid materials were stable and able to derail tumor cells (HeLa) in the case of hybrid materials with copper(II) compounds, with IC50 in the range from 0.11 to 0.41 mg/mL. Unlikely, the analogous compounds of zinc(II) and pure clays have proved to be non-toxic facing the same cells. These results indicate a promising possibility of using the beidellites as carriers of these antitumor metal complexes

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-08-22T11:23:26Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação_Eloiza da Silva Nunes.pdf: 2557684 bytes, checksum: 485672a5e5df50e25a70cde5803fbfb4 (MD5) / Made available in DSpace on 2014-08-22T11:23:26Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação_Eloiza da Silva Nunes.pdf: 2557684 bytes, checksum: 485672a5e5df50e25a70cde5803fbfb4 (MD5) Previous issue date: 2010-03-10 / In this work are described the synthesis and characterization of dinuclear rhodium(II) citrate, adsorption study in maghemite nanoparticles, and preparation of nanoparticles-modified based magnetic fluids. Rhodium(II) citrate has significant antitumor activity being promissory to cancer chemotherapy. Due to the existence of free functional groups in its molecular structure this complex has capacity to functionalize iron oxide nanoparticles to produce drug-particles formulations. The modified nanoparticles show features of biocompatibility suitable to use the system in medical applications. Rhodium(II) citrate was synthesized by an exchange reaction of trifluoroacetate ligands from the precursor rhodium(II) trifluoroacetate by citrate ligands. The products were characterized by C and H elemental and thermogravimetric analysis, mass spectrometry, and infrared, UV/visible and 13C nuclear magnetic resonance spectroscopy. The results are consistent with the formation of dinuclear structure characteristic for rhodium(II) carboxylates. Changing the synthesis conditions were obtained products with stoichiometries [Rh2(H2cit)2(H2O)4] and [Rh2(H2cit)4(H2O)2]. The results and compounds solubility observations suggest that the first one occur as a coordination polymer. The second one showed composition e solubility behavior consistent with the formation of monomeric units. Maghemite nanoparticles with size mean between 5 and 7 nm were obtained through alkaline coprecipitation of Fe2+ and Fe3+ ions with further oxidation with oxygen gas. The solids were characterized by X-ray difratometry and the Scherrer relation was use to calculate the crystallite size mean. Adsorption experimental data were adjusted to Langmuir model and linear coefficients obtained, R2, were greater than 0,99. Functionalized nanoparticles were dispersed into water producing a stable colloid. Dispersion s characterization was performed by absorbance, zeta potential, and hydrodynamic diameter measurements. Surface properties and colloidal behavior of functionalized nanoparticles are much affected by adsorbed species. The colloidal stability of the magnetic fluids is dependent on the adsorbed amounts of rhodium(II) citrate and pH. When the adsorbed amount of rhodium(II) citrate is next to saturation, the magnetic fluids are stable in pH over 3 and show hydrodynamic diameter around 60 nm. Fluids colloidal stability is preserved against physiologic saline solution, PBS buffer, and fetal bovine serum over a period of 30 days. / Neste trabalho estão descritos a síntese e a caracterização do complexo dimérico citrato de ródio(II), estudo de sua adsorção em nanopartículas de maghemita e a preparação de fluidos magnéticos á base de nanopartículas modificadas com o complexo. O citrato de ródio (II) apresenta significante atividade antitumor sendo promissor para aplicação na quimioterapia do câncer. Devido à existência de grupos funcionais livres em sua estrutura molecular esse complexo possui capacidade de funcionalizar nanopartículas de óxidos de ferro para produzir formulações droga-partícula. As nanopartículas modificadas apresentam características de biocompatibilidade adequadas para utilização do sistema em aplicações médicas. O citrato de ródio(II) foi sintetizado via reação de troca de ligantes trifluoroacetato do precursor trifluoroacetato de ródio(II) por citrato. Os produtos foram caracterizados por análise elementar de C e H e termogravimétrica, espectrometria de massas e espectroscopia nas regiões do UV/visível e infravermelho e ressonância magnética nuclear de 13C. Os resultados são consistentes com a formação da estrutura dimérica. Variando-se as condições de síntese pode-se obter produtos com estequiometrias [Rh2(H2cit)2(H2O)4] e [Rh2(H2cit)4(H2O)2]. Os resultados somados às observações sobre a solubilidade dos compostos sugerem que o primeiro ocorre como um polímero de coordenação. O segundo composto apresentou características de composição e solubilidade coerente com a formação de unidades dimetálicas monoméricas. Foram obtidas nanopartículas de maghemita com diâmetros entre 5 e 7 nm através do método de coprecipitação de íons Fe2+ e Fe3+ em meio alcalino com posterior oxidação com oxigênio gasoso. Os sólidos foram caracterizados por difratometria de raios-X e o diâmetro de cristalito calculado pela equação de Scherrer. Os dados experimentais de adsorção de citrato de ródio(II) em maghemita foram ajustados ao modelo de Langmuir sendo obtido coeficiente de regressão linear, R2, maior que 0,99. As nanopartículas funcionalizadas foram dispersas em água obtendo-se um colóide estável. As dispersões foram caracterizadas por medidas de absorvância, potencial zeta e de diâmetro hidrodinâmico. As propriedades de superfície bem como o comportamento coloidal das nanopartículas funcionalizadas são influenciadas pelas espécies adsorvidas. A estabilidade coloidal dos sóis obtidos é dependente das quantidades de citrato de ródio(II) adsorvida e do pH. Quando a quantidade de citrato de ródio adsorvida é próxima da capacidade de adsorção, os fluidos magnéticos obtidos apresentam estáveis em pH acima de 3 com diâmetros hidrodinâmicos próximos de 60 nm. A estabilidade coloidal dos fluidos obtidos é preservada frente a soluções de soro fisiológico, tampão PBS e soro fetal bovino por períodos superiores a 30 dias.

This thesis deals with the development and application of methods for asymmetric olefinations, in particular Horner-Wadsworth-Emmons (HWE) reactions, in the synthesis of certain natural products. Relying on asymmetric HWE reactions to access key building blocks, two natu-ral products, pyranicin and pyragonicin, were synthesized from common late intermediates. The utility of the HWE reactions is highlighted through a desymmetrization of a meso-dialdehyde as well as a stereoconvergent reaction sequence employing the sequential use of a HWE parallel kinetic resolution fol-lowed by a Pd-catalyzed allylic substitution to convergently transform a race-mate to a single stereoisomer of the product. Methodological extensions of these syntheses include a divergent synthesis of 2,3,6-substituted tetrahydropyran derivatives and application of Zn-mediated asymmetric alkynylations to install key stereocenters. Synthetic studies directed towards a more complex target, mucocin, employing a triply convergent strategy, have also been performed. Expedient and reliable routes to three key fragments were developed, as well as methodology to access to all nine stereocenters. The fragment coupling to assemble the oligonuclear core still remains a challenge, however. Key features of the synthesis include the formation of two fragments from a common precursor derived from an asymmetric HWE desymmetrization, Zn-mediatedated asymmetric alkynylations, a stereoselective oxa-Michael cyclization dependent on a simultaneous protective group migration and a one-pot procedure for the synthesis of a TBS protected iodohydrin from a terminal epoxide. An investigation of the possibilities for developing a transition metal catalyzed asymmetric olefination using a chiral Re-complex is outlined. An enantioen-riched BINAP-Re complex was synthesized and characterized by X-ray. An efficient protocol for the olefination of functionalized aldehydes employing this catalyst was developed, but gave racemic products in two attempted kinetic resolutions of racemic substrates, most likely due to a reaction pathway proceeding via a non-metal associated phosphonium ylide. / QC 20100921