Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-29T14:00:29Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Minha dissertação final para biblioteca.pdf: 6771552 bytes, checksum: cc238895a0629230ce30655a760f5a10 (MD5) / Made available in DSpace on 2016-04-29T14:00:29Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Minha dissertação final para biblioteca.pdf: 6771552 bytes, checksum: cc238895a0629230ce30655a760f5a10 (MD5) Previous issue date: 2015-02-19 / CAPEs / Estima-se que até 2030 o câncer será responsável por até 12 milhões de óbitos. Tendo em vista a necessidade de novos tratamentos para o câncer, este trabalho tem como objetivo sintetizar, caracterizar estruturalmente e avaliar a atividade anticâncer de sete novos derivados tiazacridínicos (LPSF AA-56, LPSF AA-57, LPSF AA-59, LPSF AA-60, LPSF AA-61, LPSF AA-62, LPSF AA-63). Estes derivados provém da hibridização molecular dos núcleos de tiazolidina e de acridina. As sínteses para obtenção destes compostos foram otimizadas para obtenção de um melhor rendimento. A síntese da tiazolidina-2,4-diona (TZD) foi feita por reação de ciclização. Uma posterior N-alquilação da TZD em presença de uma base e da 9-(bromo-metil)acridina, conduziu a formação do intermediário LPSF AA-1A. Os intermediários ésteres de Cope (IPs) foram obtidos a partir de uma reação de condensação Knoevenagel. A última etapa ocorreu por uma reação de adição de Michael através de reação entre a TZD N-alquilada com os ésteres de Cope, formando os derivados tiazacridínicos substituídos. A pureza e comprovação estrutural das moléculas sintetizadas foram obtidas através de cromatografia líquida acoplada a espectrômetro de massa (LC-MS), infravermelho (IV) e ressonância magnética nuclear (RMN) de hidrogênio. Ensaios de citotoxicidade dos derivados sintetizados foram realizados em células leucêmicas, fígado e próstata. Entre os compostos sintetizados, o LPSF AA-57 exibiu a atividade anti-cancerígena mais potente contra as linhagens celulares Jurkat (6,63 ± 2,65 μM), HL-60 (6,51 μM), K562 (3,97 ± 1,36 μM) e o LPSF AA-60 exibiu a atividade anti-cancerígena mais potente contra DU 145 (7,22 ± 3,12 μM). / It is estimated that cancer will be responsible for up to 12 million deaths by 2030. Given the need for new treatments for cancer this work aims to synthesize, characterize structurally and evaluate the anti-cancer activity of seven new thiazacridines derivatives (LPSF AA-56, LPSF AA-57, LPSF AA-59, LPSF AA-60, LPSF AA-61, LPSF AA-62, and LPSF AA-63). These derivatives derived of molecular hybridization from nucleus of thiazolidine and acridine. The syntheses for obtaining these compounds were optimized to obtain the best performance. Synthesis of thiazolidine-2,4-dione (TZD) was carried out by cyclization reaction. A further N-alkylation of the TZD in the presence of a base and 9-(bromomethyl)acridine, leading to formation of intermediate LPSF AA-1A. Intermediate esters of Cope (IPs) were obtained from a Knoevenagel condensation reaction. The last step was by a Michael addition, reaction between the N-alkylated TZD with ester of Cope, forming substituted thiazacridines derivatives. The purity and structural confirmation of the synthesized molecules were obtained from liquid chromatography coupled to mass spectrometry (LC-MS), infrared (IR) and Proton nuclear magnetic resonance (NMR). Assays of cytotoxicity of the synthesized products was conducted in leukemic cells, liver and prostate. Among the synthesized compounds, the LPSF AA-57 exhibited the most potent anti-cancer activity against cell lines Jurkat (6,63 ± 2,65 μM), HL-60 (6,51 μM), K562 (3,97 ± 1,36 μM) and the LPSF AA-60 exhibited the most potent anti-cancer activity against DU 145 (7,22 ± 3,12 μM).

Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2017-05-04T19:42:55Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE.ELIZABETH.ALMEIDA.LAFAYETTE..pdf: 5409552 bytes, checksum: e75a96e9227604d98bcc02d9668c2c4a (MD5) / Made available in DSpace on 2017-05-04T19:42:55Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE.ELIZABETH.ALMEIDA.LAFAYETTE..pdf: 5409552 bytes, checksum: e75a96e9227604d98bcc02d9668c2c4a (MD5) Previous issue date: 2016-05-27 / FACEPE / O DNA é um significativo receptor celular, onde muitos compostos químicos exercem seus efeitos antitumorais. A ligação de drogas ao DNA pode afetar a sua transcrição e a expressão da informação genética nas células, influenciando assim, na inibição do crescimento de células antitumorais, que é a base da concepção de fármacos mais eficazes. Moléculas com núcleos indois e acridínicos são biologicamente ativas e possuem atividades como antitumoral, antituberculose, anti-inflamatória e antiasmática; associado não apenas a interação com o DNA, mas também com proteínas, especialmente algumas enzimas-chaves na proliferação celular, as topoisomerases. Com base nestas informações, este trabalho teve como objetivo a síntese de onze novos derivados indólicos com anéis 3-amino-2-tioxo-tiazolidin-4-ona, 2-tioxo-tiazolidin-4-ona, tiazolidin-4-ona e 2-tioxo-imidazolidin-4-ona condensados como cadeias laterais e a síntese de oito novos derivados acridínicos com diferentes tiosemicarbazidas condensadas. Além disso, objetivou-se verificar a atividade antitumoral, investigar a capacidade de interação o DNA e atividade antitopoisomerase dos novos derivados obtidos. Os derivados foram sintetizados com êxito, com ponto de fusão em faixa de pureza e com estruturas elucidadas e comprovadas por espectrometria de massas (MS), infravermelho (IV), técnicas espectroscópicas unidimensionais de RMN1H e RMN13C, e algumas técnicas espectroscópicas bidimensionais, como COSY1H-1H e HSQC1H-13C. A avaliação antitumoral foi realizada com diferentes linhagens de células cancerígenas, por meio do ensaio antiproliferativo MTT e Sulforrodamina B. A análise da ligação ao DNA foi conduzido através da espectroscopia de absorção e da fluorescência utilizando o brometo de etídio (BE) como sonda fluorescente. Os derivados testados exibiram mudanças em suas propriedades espectroscópicas após a interação com ctDNA (DNA de timo bovino), com efeitos hipocrômico e hipercrômico, além de alterações na forma com desvio para a região do vermelho e do azul. Na série das acridinas testadas, o composto mais ativo no teste antiproliferativo foi o derivado não substituido (LT.26) na porção tiossemicarbazona, e o derivado com o substituinte cloro (LT.27) mostrou-se o mais eficiente na ligação com o DNA. Dentre os derivados indólicos, o composto com o grupamento amino livre e não substituído no anel indólico (SE.01) se destacou com eficácia nas linhagens de leucemias testadas e com o alto valor da constante de ligação ao DNA, Kb de 5.69 x 104, aliado a maior supressão da fluorescência, Ksv = 1.81 x 104, assegurando a participação do grupamento amino na interação com o DNA. O derivado indólico SE.05 apresentou destaque importante como compostos promissor, com atividade antitumoral para uma linhagem de mama testada, por apresentar potência superior ao controle positivo, a doxorrubicina. O derivado bis-indólico (TE.04) sintetizado, apresentou também eficácia nas linhagens de câncer testadas, entretanto com menor capacidade de ligação ao DNA. O derivado indólico SE.01 e TE.04 destaque foram conduzidos a uma avaliação da inibição da enzima topoisomerase I humana, porém mostraram-se ineficientes na inibição até a concentração de 50 μM analisada. Tais resultados mostram que o núcleo indol e acridínico, associados a heterocíclicos tiazolidinicos, imidazolidinicos e tiosemicarbazonas, são promissores como agentes antitumorais, com potencial capacidade de interação com o DNA. / DNA is a major cellular receptor, where many chemical compounds exercise their antitumor effects. The DNA binding drugs may affect its transcription and expression of genetic information in cells, thereby influencing, in inhibiting the growth of antitumor cells, which is the basis for design of more effective drugs. Molecules with indoles and acridines ring are biologically active and have activities such as anticancer, anti-tuberculosis, anti-inflammatory and anti-asthamatic; associated not only the interaction with DNA, but also to proteins, especially some key enzymes in cell proliferation, topoisomerases. Bases on this information, this study had as objective to the synthesis of eleven new indole derivatives with heterocyclic rings 3-amino-2-thioxo-thiazolidin-4-one, 2-thioxo-thiazolidin-4-one, thiazolidin-4-one and 2-thioxo-imidazolidin-4-one condensed as side chains; and synthesis of eight new derivatives acridine with different condensed thiosemicarbazides. Moreover, the objective was to determine the antitumor activity, investigate their ability to interact DNA and anti-topoisomerase activity. The derivative were synthesized successfully, with a melting range in purity and elucidated structures and proven by mass spectrometry (MS), infrared (IR), spectroscopic one-dimensional 1H NMR, 13C NMR, and some dimensional spectroscopic techniques such as COSY1H-1H and HSQC1H-13C. The antitumor evaluation was performed with different cancer cell lines, using the antiproliferative assay MTT and sulforrodamina B. Analysis of DNA binding was executed by absorption spectroscopy and fluorescence using ethidium bromide (EB) as a fluorescent probe. The derivatives tested exhibited changes in their spectroscopic properties, after interacting with ctDNA (DNA calf thymus), with hypochromic and hyperchromic effects and changes in form with deviation to the region of the red and blue. In the series of acridines tested, the most active compound in the antiproliferative test was the unsubstituted derivative (LT.26) in thiosemicarbazone moiety, and acridine derivative with the chloro substituent (LT.27) proved to be the most efficient in binding to DNA. Among the indole derivatives, the compound with the free amino group and unsubstituted in the indole ring (SE.01) was highlighted effectively tested on leucemia lines and the high value of the DNA binding constant, Kb of 5.69 x 104 ally to greater suppression of fluorescence, Ksv of 1.41 x 104, ensuring the participation of the amino group in the interaction with DNA. The indole derivative SE.05 presented significant attention as promising compounds with antitumor activity for a breast line tested by presenting power greater than the positivi control, doxorubicin. The bis-indole derivative synthesized (TE.04) also exhibit efficacy in cancer cell lines tested, however with lower DNA binding capacity. The indole derivatives SE.01 and TE.04 highlighted were conducted an evaluation of the inhibition of the enzyme topoisomerase I human, but proved to be inefficient in inhibition to the concentration of 50 μM analyzed. These results show that the indole and acridine nucleus, associated with thiazolidine and imidazolidine heterocyclic and thiosemicarbazones, are promising as antitumor agents with the potential ability to interact with DNA.

Simple and novel nuclease models have been synthesized. These involve metal-binding ligand 1,4,7,10-tetraazlcyclododecane (cyclen) tethered to an acridine ring (a DNA-binding group) by amide linkers of various lengths. Binding of these probes to DNA was studied by monitoring changes in their UV-visible spectra affected by the presence of DNA. Titration of these compounds with increasing amounts of pBR322 DNA caused hypochromic effects and shifted the acridine absorption at 360nm to a longer wavelength. Under biologically relevant conditions (37°C and pH 7.4), specific transition metal complexes of these compounds are found to be highly effective catalysts toward the hydrolysis of plasmid DNA. This is demonstrated by their ability to convert the super-coiled DNA (form I) to open-circular DNA (form II). Structure-activity correlation studies show that hydrolytic activity depends on both the structure of ligand (L1>L2>L3) and the nature of metal ion cofactor (Co3+>Zn2+>Cr2+>Ni2+>Cu2+>Fe3+).

We have identified a small library of novel substituted 9-aminoacridine derivatives that inhibit cell proliferation of pancreatic cancer cell lines by inducing apoptosis [Goodell, J.R. et al., 2008. J. Med. Chem. 51, 179-182.]. To further investigate their antiproliferative activities, we have assessed the antiproliferative activity of these acridine-based compounds against several pancreatic cancer cell lines. All four compounds used in this study inhibited the proliferation of pancreatic cancer cell lines in vitro. In addition, we have employed a xenograft tumor model and found that these compounds also inhibit the proliferation of pancreatic cancer in vivo. In light of the potential importance of the anticancer activity of these acridine-based compounds, we have conducted a series of biochemical assays to determine the effect of these compounds on human topoisomerase II. Unlike amsacrine, these compounds do not poison topoisomerase II. Similar to amsacrine, however, these compounds intercalate into DNA in a way that they would alter the apparent topology of the DNA substrate. Thus, inhibition of the relaxation activity of topoisomerase II by these compounds has been reexamined using a DNA strand passage assay. We have found that these compounds, indeed, inhibit the catalytic activity of topoisomerase II. Thus, these novel acridine-based compounds with anti-pancreatic cancer activity are catalytic inhibitors, not poisons, of human topoisomerase II.

No description available.

The sperm chromatin structure assay (SCSA), as developed by Evenson et al.(1980), utilizes flow cytometry to quantify the susceptibility of sperm chromatin to in situ acid denaturation via the metachromatic properties of acridine orange. SCSA is repeatable and has been used to distinguish between fertile and subfertile males in different species; however, it does not permit morphological evaluation of cells. In the present study, the SCSA was modified for the fluorescence/differential interference contrast (DIC) microscope to examine morphology and chromatin stability on the same cell. Semen from six Holstein bulls was collected twice weekly for six weeks. Semen was cryopreserved after collection. A 48-hr scrotal insulation was applied after the first three collections to exert a mild thermal insult to the testes; this induces specific spermatozoal morphological abnormalities to appear in a predictable chronological order, as determined by Vogler et al. (1993). Using DIC optics, sperm head morphology was classified as normal, slightly misshapen, pyriform, severely misshapen, or tailless. Vacuolization in the head region was scored separately as apical, diadem, or random. SCSA and modified-SCSA for fluorescence microscopy were used to assess chromatin instability in the samples. The SCSA parameter of 'cells outside the main population of alpha t' (%COMP alpha t) and the modified-SCSA parameter of '% cells shifted from green' were positively correlated (r=0.84; P<0.01). Both variables were positively correlated with the appearance of tailless, pyriform, severely misshapen, and randomly vacuolated cells (P< 0.01), but not with the appearance of diadems or apical vacuoles. Also, the fluorescence microscope detected a significant shift from green in normally shaped cells appearing in morphologically abnormal ejaculates (P<0.01). These results demonstrate that scrotal insulation-induced morphological abnormalities in spermatozoa signify a perturbation in chromatin structure, and that the chromatin perturbation extends into normally shaped cells in the same ejaculate. / Master of Science

Following active growth, the aquatic gram-negative rod Prolinoborus fasciculus (Aquaspirillum fasciculus) exhibited a mass conversion from its culturable rod form to a nonculturable coccoid form. Chloramphenicol did not prevent the conversion. Attempts to obtain variants that would not convert to the coccoid form were unsuccessful. Although the coccoid form fluoresced with acridine orange, agarose gel electrophoresis revealed extensive ribosomal RNA degradation. Poly-Ã -hydroxybutyrate, abundant in the vegetative rods, was not detectable in the coccoid cells. The results suggest that the coccoid form of A. fasciculus is a degenerative form rather than part of a life cycle. / Master of Science

Le développement des nanoparticules fluorescentes, appelées quantum dots (QDs) est devenu l'un des domaines les plus prometteurs de la science des matériaux. Dans cette étude une procédure de synthèse de QDs a été mise au point, comprenant la synthèse de noyaux ultra-minces de CdSe, la purification de noyau haute performance, le revêtement central avec une coquille épitaxiale en ZnS. Cette approche a permis d’obtenir des QDs d’une taille de 3,7 nm possédant un rendement quantique supérieur à 70%. Les QDs développés ont été utilisés pour concevoir des conjugués de QDs compacts avec les nouveaux dérivés d'acridine, ayant une affinité élevée pour le G-quadruplex des télomères, ainsi que leur effet inhibiteur sur la télomérase, une cible importante du traitement du cancer. Les résultats de cette étude ouvrent la voie à l'ingénierie de nanosondes multifonctionnelles possédant une meilleure pénétration intracellulaire, une plus forte brillance et une stabilité colloïdale plus importante. / Development of the fluorescent nanoparticles referred to as quantum dots (QDs) has become one of the most promising areas of materials sciences. In this study, a procedure of synthesis of QDs, which includes the synthesis of ultrasmall CdSe cores, high-performance purification, core coating with an epitaxial ZnS shell has been developed. This approach has allowed obtaining 3.7-nm QDs with a quantum yield exceeding 70%. The QDs have been used: to engineer compact conjugates of QDs with the novel acridine derivatives, which have a high affinity for the telomere G-quadruplex; to demonstrate their inhibitory effect on telomerase, an important target of anticancer therapy; and to accelerate transmembrane penetration of ultrasmall QDs into cancer cells while retaining a high brightness and colloidal stability. The results of this study pave the way to the engineering of multifunctional nanoprobes with improved intracellular penetration, brightness, and colloidal stability.

Malaria endemic areas not only pose a public health threat, but affects 3.3 billion people worldwide. In 2011, estimated malaria related deaths amounted to 660 000 out of 219 million reported cases, with 81% of these and 91% of malaria related mortality occurred in the African region. Those most affected were pregnant women, children under the age of five and immunocompromised individuals. Malaria is the fifth deadliest disease worldwide and accounts for the second highest death rate in Africa, following HIV/Aids. To combat this parasitic infection of antiquity, the ideal malaria pharmacotherapy would be a cost effective and easily obtainable monotherapy. The malaria parasite, however, has an intrinsic ability to develop drug resistance through various mechanisms. Widespread resistance towards antimalarial drugs has rendered traditionally used drugs therapeutically ineffective, hence accentuating the efficacy of the artemisinins as first line treatment option for uncomplicated Plasmodium falciparum (P. falciparum). A devastating reality of the challenging battle against malaria is the confirmed prolonged parasitic clearance times of the artemisinins, despite adequate drug exposure, which emphasises the urgent need for identifying and developing new, effective and safe therapies. During this study, 9-aminoacridines and artemisinin-acridine hybrids were successfully synthesised through nucleophillic substitution and their chemical structures confirmed by means of nuclear magnetic resonance spectroscopy (NMR), high resolution mass spectroscopy (HRMS) and infrared spectroscopy (IR). The hybrid compounds were synthesised through microwave assisted radiation, by covalently linking the artemisinin- and amino-functionalised acridine pharmacophores by means of a liable aminoethyl ether chain. The target compounds were screened in vitro for antimalarial activity against both the chloroquine sensitive (NF54) and chloroquine resistant (Dd2) strains of P. falciparum. Their cytotoxicities were assessed against various mammalian cells of different origins, viz. the Chinese hamster ovarian cells (CHO) from animal origin, and from human origin, hepatocellular- (HepG2), neuroblastoma- (SH-SY5Y) and cervical cancer (HeLa) cells. The synthesised hybrids exhibited antimalarial activity against both Plasmodium strains. Compound 7, featuring an ethylenediamine moiety in the linker, was the most active hybrid, with 50% inhibitory concentration (IC50) values of 2.6 nM and 35.3 nM against the NF54 and Dd2 strains, respectively. It had gametocytocidal activity against the NF54 strain, comparable to dihydroartemisinin (DHA) and artesunate (AS) and it is significantly more potent than chloroquine (CQ), whilst possessing a resistance index value of 14, indicative of a significant loss of activity against the CQ resistant strain. Contrary, the promising hybrid 10, containing a 2-methylpiperazine linker, had gametocytocidal activity, comparable to CQ and was found to be six-fold more potent than CQ against the Dd2 strain, with a resistance index (RI) value of 2, whilst it further showed highly selective action towards the parasitic cells. Compound 10 was also found to possess anticancer activity against the HeLa cell line, comparable to DHA and AS, but fivefold higher than that of CQ, with the same levels of hepatotoxicity and neurotoxicity. The artemisinin-acridine hybrids displayed superior antimalarial activity, compared to the derived 9-aminoacridines against both the Plasmodium strains. They, however, did not have the ability to overcome resistance, reduce the toxicity of acridine, nor induce synergistic activity. The hybrids, indeed displayed promising anticancer activity against HeLa cells. It is anticipated that these compounds may stand as drug candidates for further investigation in the search for new anti-cervical cancer drugs, rather than as antimalarials. / MSc (Pharmaceutical Chemistry), North-West University, Potchefstroom Campus, 2014

Malaria endemic areas not only pose a public health threat, but affects 3.3 billion people worldwide. In 2011, estimated malaria related deaths amounted to 660 000 out of 219 million reported cases, with 81% of these and 91% of malaria related mortality occurred in the African region. Those most affected were pregnant women, children under the age of five and immunocompromised individuals. Malaria is the fifth deadliest disease worldwide and accounts for the second highest death rate in Africa, following HIV/Aids. To combat this parasitic infection of antiquity, the ideal malaria pharmacotherapy would be a cost effective and easily obtainable monotherapy. The malaria parasite, however, has an intrinsic ability to develop drug resistance through various mechanisms. Widespread resistance towards antimalarial drugs has rendered traditionally used drugs therapeutically ineffective, hence accentuating the efficacy of the artemisinins as first line treatment option for uncomplicated Plasmodium falciparum (P. falciparum). A devastating reality of the challenging battle against malaria is the confirmed prolonged parasitic clearance times of the artemisinins, despite adequate drug exposure, which emphasises the urgent need for identifying and developing new, effective and safe therapies. During this study, 9-aminoacridines and artemisinin-acridine hybrids were successfully synthesised through nucleophillic substitution and their chemical structures confirmed by means of nuclear magnetic resonance spectroscopy (NMR), high resolution mass spectroscopy (HRMS) and infrared spectroscopy (IR). The hybrid compounds were synthesised through microwave assisted radiation, by covalently linking the artemisinin- and amino-functionalised acridine pharmacophores by means of a liable aminoethyl ether chain. The target compounds were screened in vitro for antimalarial activity against both the chloroquine sensitive (NF54) and chloroquine resistant (Dd2) strains of P. falciparum. Their cytotoxicities were assessed against various mammalian cells of different origins, viz. the Chinese hamster ovarian cells (CHO) from animal origin, and from human origin, hepatocellular- (HepG2), neuroblastoma- (SH-SY5Y) and cervical cancer (HeLa) cells. The synthesised hybrids exhibited antimalarial activity against both Plasmodium strains. Compound 7, featuring an ethylenediamine moiety in the linker, was the most active hybrid, with 50% inhibitory concentration (IC50) values of 2.6 nM and 35.3 nM against the NF54 and Dd2 strains, respectively. It had gametocytocidal activity against the NF54 strain, comparable to dihydroartemisinin (DHA) and artesunate (AS) and it is significantly more potent than chloroquine (CQ), whilst possessing a resistance index value of 14, indicative of a significant loss of activity against the CQ resistant strain. Contrary, the promising hybrid 10, containing a 2-methylpiperazine linker, had gametocytocidal activity, comparable to CQ and was found to be six-fold more potent than CQ against the Dd2 strain, with a resistance index (RI) value of 2, whilst it further showed highly selective action towards the parasitic cells. Compound 10 was also found to possess anticancer activity against the HeLa cell line, comparable to DHA and AS, but fivefold higher than that of CQ, with the same levels of hepatotoxicity and neurotoxicity. The artemisinin-acridine hybrids displayed superior antimalarial activity, compared to the derived 9-aminoacridines against both the Plasmodium strains. They, however, did not have the ability to overcome resistance, reduce the toxicity of acridine, nor induce synergistic activity. The hybrids, indeed displayed promising anticancer activity against HeLa cells. It is anticipated that these compounds may stand as drug candidates for further investigation in the search for new anti-cervical cancer drugs, rather than as antimalarials. / MSc (Pharmaceutical Chemistry), North-West University, Potchefstroom Campus, 2014