No description available.

No description available.

No description available.

In the first part of this thesis, the synthesis, characterization and investigation of ortho-phenyleneethynylenes containing heterocycles, are presented. These compounds display changes in absorption and emission spectra varying with their functionalization and size. These compounds also have the ability to coordinate with metals. The synthesis of coordination compounds and their crystallographic data are reported. The synthesis and characterization of tetraethynyl thiophene compounds containing pyridines are also presented. These compounds exhibit differences in absorption and emission spectra upon exposure to various metal salts. The final topic to be discussed is the synthesis and characterization of diphenyl amine polymers. These polymers could in principle be used in NLO applications or light emitting devices.

Thesis (Ph. D.)--University of Alabama at Birmingham, 2007. / Additional advisors: Houston Boyd, Tracy Hamilton, Christopher Lawson, Charles Watkins. Description based on contents viewed Feb. 8, 2008; title from title screen. Includes bibliographical references.

Thesis (D.Phil.(Chemistry))-University of Pretoria, 2006. / Includes bibliographical references. Available on the Internet via the World Wide Web.

Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2017-05-04T19:22:54Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Jamerson Ferreira de Oliveira.pdf: 8179635 bytes, checksum: 1f2c547f3d5adc66855c8a64ba2e148e (MD5) / Made available in DSpace on 2017-05-04T19:22:54Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese Jamerson Ferreira de Oliveira.pdf: 8179635 bytes, checksum: 1f2c547f3d5adc66855c8a64ba2e148e (MD5) Previous issue date: 2016-03-07 / Facepe / O câncer é um grave problema de saúde pública o qual afeta milhares de pessoas no mundo. Sabe-se que há uma estreita relação entre o câncer e a inflamação onde o microambiente inflamatório favorece a progressão tumoral. Baseado nessas evidências, foi proposto neste trabalho, a síntese de novas moléculas híbridas contendo as subunidades das tiossemicarbazonas e do tiofeno que detêm as atividades antitumoral e anti-inflamatória. Uma nova série de 2-tiofenotiossemicarbazonas (5-14) foi sintetizada, caracterizada e avaliada a atividade biológica. A síntese demonstrou ser eficiente onde foi possível encontrar rendimentos reacionais satisfatórios que variaram de 40-87%. A atividade antiproliferativa in vitro foi realizada através do método colorimétrico da sulforrodamina B, onde os derivados 7 (p-bromo-fenil) e 9 (p-metil-fenil) foram os que mais se destacaram. O composto 7 se destacou frente à linhagem NCIADR/ RES com GI50 1.7 μM, já o composto 9 se destacou na linhagem K-562 com GI50 <0.9 μM. O composto 7 foi eleito, dentre os demais derivados avaliados no ensaio in vitro, para o prosseguimento dos estudos. Através da citometria de fluxo foi possível evidenciar que o composto induz a exposição de fosfatidilserina (apoptose inicial), porém esse mecanismo de morte celular é independente do ciclo celular. Os estudos in vivo foram realizados utilizando o modelo de tumor de pata de Ehrlich. Das três doses utilizadas (30, 100 e 300 mg/Kg) a dose de 30 mg/Kg foi capaz de controlar o crescimento tumoral na pata dos camundongos nos dias 6 (60.6 ± 4.6), 9 (57.1 ± 5.2) e 12 (36.3 ± 6.6). Adicionalmente a atividade antitumoral, também foram realizados ensaios a fim de avaliar as atividades antinociceptiva e anti-inflamatória. O ensaio de nocicepção induzido pela formalina revelou que o composto 7 apresentou atividade nas duas fases da dor, ressaltando a dor inflamatória, onde o derivado foi capaz de reduzir o tempo de lambida da pata em 62.3, 84.30 e 100% nas doses de 30, 100 e 300 mg/Kg, respectivamente. Acerca da atividade anti - inflamatória, foi realizado o edema de orelha induzido por óleo de cróton, onde nenhuma das doses testadas foi capaz de regredir significativamente o edema produzido. O edema de pata induzido pela carragenina mostrou ação do composto, onde o edema foi reduzido em 81.9 e 83.2% nos tempos 1 e 2 horas do experimento na dose de 300 mg/Kg. Isso sugere uma ação sobre os mediadores iniciais da inflamação. O ensaio de edema de pata induzido pelo composto 48/80 confirmou essa hipótese, no qual o composto 7, após 15 minutos do inóculo do agente flogístico, demonstrou redução significativa do edema apresentando valores de 56.53% na dose de 30 mg/Kg indicando uma ação do composto sobre a serotonina e a histamina. Os estudos iniciais, realizados acerca da investigação do potencial biológico das 2-tiofeno-tiossemicarbazonas, revelaram a importância dessa classe de compostos no câncer e na inflamação. No entanto, estudos minuciosos necessitam ser realizados a fim de contribuir na descoberta de novos fármacos. / Cancer is a major public health issue which affects thousands of people worldwide. It is known that there is a close relationship between cancer and inflammation where the inflammatory microenvironment promotes tumor progression. Based on this evidence, it is proposed in this paper the synthesis of new hybrid molecules containing the subunits of thiosemicarbazone and thiophene holding the anti-tumor and anti-inflammatory activities. A new series of 2-thiophene-thiosemicarbazones (5- 14) was synthesized, characterized and evaluated to the antitumor and antiinflammatory activity. The synthesis was demonstrated efficient where it was possible to find satisfactory reaction yields ranging from 40-87%. The antiproliferative activity in vitro was performed using the colorimetric method sulforhodamine B. The derivatives 7 (p-bromophenyl) and 9 (p-methylphenyl) obtained good GI50 values. The compound 7 stood out against NCI-ADR/RES lineage (multidrug resistant ovarian) with GI50 1.7 μM, as the compound 9 stood out in the K-562 strain (leukemia) with GI50 <0.9 μM. Compound 7 was elected from among the other derivatives evaluated in vitro assay, for further studies. By flow cytometry it became clear that the compound induces phosphatidylserine exposure (early apoptosis), but this cell killing mechanism is independent of the cell cycle. In vivo studies were performed using the model Ehrlich paw tumor. Of the three doses used (30, 100 and 300 mg/Kg) dose of 30 mg/Kg was able to control tumor growth in the paw of mice on days 6 (60.6 ± 4.6), 9 (57.1 ± 5.2) and 12 (36.3 ± 6.6). In addition to antitumor activity, also forms tests performed to evaluate the antinociceptive and antiinflammatory activities. The nociception induced by formalin test revealed that the compound 7 showed activity in both phases of pain, emphasizing the inflammatory pain, where it was able to reduce the time of paw lick 62.3, 84.30 and 100% at doses of 30, 100 and 300 mg/kg, respectively. About anti-inflammatory activity was performed ear edema induced by croton oil, where any of the doses tested was able to significantly decrease edema produced. The paw edema induced by carrageenan showed activity of the compound, where the edema was reduced 81.9 and 83.2% in the first two times of the experiment at the highest dose used (saline: 18.85 ± 2.63, 32.86 ± 4.97 and 3 JF-300 mg/Kg: 3.41 ± 1.4, 1.96 ± 5.53). This suggests an action on the initial mediators of inflammation. The paw edema assay induced by compound 48/80 confirmed our hypothesis, in which the compound 7 after 15 minutes from the inoculum phlogistic agent, showed a significant reduction of edema with values of 56.53% at the dose of 30 mg/kg (saline: 71.10 ± 6.6 JF-3 and 30 mg/kg: 30.9 ± 5.75), indicating an action of the compound on the serotonin and histamine. Initial studies conducted research on the biological potential of 2-thiophene-thiosemicarbazones, showed good activity of this class of compounds in cancer and inflammation. However, detailed studies to determine the mechanism of action by which act the thiosemicarbazone, need to be performed in order to contribute to the discovery of new drugs.

No description available.

Researchers use metal-thiophene complexes to mimic reactions which occur inside hydrodesulfurization (HDS) reactors. Information obtained from these model studies may often be applied to understanding the mechanisms involved with commercially used catalysts. Certain mechanisms¹ for HDS propose thiophene ring cleavage,forming a metallacycle, prior to hydrogenation of one double bond. There are, however, limited examples of complexes derived from C-S cleavage.^2,3,4 Thermal reactions of the iridium complex, [Ir(COD)(PMe₃₎₃]Cl (COD=1,5- cyclooctadiene), with thiophene, thiazole, 4-methyl thiazole and 5-methyl thiazole yields the C-S addition metallacycles (Me₃P)₃Ir-(CH=CHCH=S)CI (I), \ (Me3P)3Ir-(CH=NCH=CHS)CI (II), (Me3P)3Ir-CCH=NC(CH3)=CHS)CI (III) and (Me3P)3Ir (CH=NCH=C(CH3)S)CI (IV), respectively. These compounds were characterized using the following methods: ¹H NMR, ¹³C NMR, ³¹P NMR, elemental analysis and single crystal x-ray diffraction. Following C-S addition to [Ir(COD)(PMe3)3]CI, nitrogen present in the thiazoles exhibit enhanced nucleophilicity. For exmnple, compounds II-IV react with methylene chloride to form dimers: CH2[NCR=CR'SIr(Cl)(PMe3)3CH]2. The above compounds are soluble in water and react with PF6 salts liberating the chloride atom from the Ir center. pKb measurements were recorded as well. This thesis describes the synthesis and examination of con1pounds I-IV as they may model the HDS process. Compounds II-IV represent the first examples of ring opened thiazole metallacycles with iridium. / Master of Science

Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Please see fulltext for abstract / AFRIKAANSE OPSOMMING: Sien asb volteks vir opsomming