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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.
1

Síntese e avaliação das atividades citotóxica e inibitória da formação de biofilmes bacterianos de gama-alquilideno-gama-lactonas cloradas e gama- lactamas derivadas / Synthesis and evaluation of cytotoxic activities and inhibitory of the formation of bacterial biofilms of gamma-alkylidene-gamma-lactones chlorinated and gamma-lactams derivatives

Moreira, Thaís Altoé 23 February 2015 (has links)
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2016-05-06T16:54:51Z No. of bitstreams: 1 texto completo.pdf: 2543097 bytes, checksum: 2cf75ea8db42a45b228e5bd1fc41258d (MD5) / Made available in DSpace on 2016-05-06T16:54:51Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2543097 bytes, checksum: 2cf75ea8db42a45b228e5bd1fc41258d (MD5) Previous issue date: 2015-02-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Os butenolídeos, γ-lactonas insaturadas, estão presentes na estrutura de um grande número de produtos naturais e apresentam uma variedade de atividades biológicas, tais como fungicida, bactericida, anti-inflamatória, citotóxica e reguladora de germinação de sementes. Essas atividades também são descritas para as γ-hidroxi- γ-lactamas e γ-alquilideno-γ-lactamas que estão presentes em vários produtos naturais biologicamente ativos. Visando contribuir com o estudo dessas classes de compostos, esse trabalho teve como objetivo sintetizar novas γ-alquilideno-γ- lactonas e seus correspondentes γ-hidroxi-γ-lactamas e γ-alquilideno-γ-lactamas, além de avaliar suas atividades citotóxica e inibitória da formação de biofilmes bacterianos. Na rota sintética escolhida, o ácido mucoclórico, utilizado como material de partida, foi inicialmente reduzido a 3,4-diclorofuran-2(5H)-ona e posteriormente reagiu com diferentes aldeídos aromáticos por meio da reação de alquilidenação, resultando no preparo de oito diferentes γ-alquilideno-γ-lactonas. Três desses análogos foram convertidos nas γ-hidroxi-γ-lactamas correspondentes pela reação de conversão lactona-lactama com isobutilamina e propilamina, e a subsequente desidratação das γ-hidroxi-γ-lactamas resultou na formação das (Z) e (E)-γ- alquilideno-γ-lactamas. Todos os compostos sintetizados foram caracterizados por espectroscopia no IV, espectroscopia de RMN de H e de 13 C, técnicas bidimensionais COSY e HETCOR e espectrometria de massas, além de experimentos de NOEDIF para determinar a estereoquímica da ligação dupla das unidades γ-alquilideno-γ-lactamas. O ensaio de citotoxicidade foi realizado com as linhagens celulares de câncer humano OVCAR-8, SF-295, HCT-116 e HL-60. Os resultados mostraram que as γ-lactonas são mais ativas do que as γ-lactamas. Os melhores efeitos citotóxicos observados estão relacionados a lactona (5Z)-3,4- dicloro-5-(4-bromobenzilideno)furan-2(5H)-ona (21), que apresentou significativa atividade contra as quatro linhagens celulares de câncer humano testadas. Em particular, a lactona 21 apresentou CR 50 = 0,66 μg/mL contra HL-60. No ensaio de inibição da formação de biofilme bacteriano de Streptococcus mutans, o melhor resultado foi observado para a lactona (5Z)-3,4-dicloro-5-(4- trifluorometilbenzilideno)furan-2(5H)-ona (26) que apresentado IC 50 equivalente a 0,21 ± 0,05 μg/mL. / The butenolides, γ-unsaturated lactones, are present in the structure of many natural products, and exhibit a variety of biological activities, such as fungicide, bactericide, anti-inflammatory, cytotoxicity and regulation of seed germination. These activities are also described for γ-hydroxy-γ-lactams and γ-alkylidene-γ-lactams which are present in many biologically active natural products. To contribute to the study of these classes of compounds, this study aimed to synthesize new γ-alkylidene-γ- lactones and their corresponding γ-hydroxy-γ-lactams and γ-alkylidene-γ-lactams and to evaluate their cytotoxicity and formation of bacterial biofilms inhibition. In the chosen synthetic route, the mucochloric acid was inittially reduced to 3,4- diclorofuran-2(5H)-one which subsequently reacted with various aromatic aldehydes through the reaction of aldol condensation, resulting in the preparation of eight different γ-alkylidene-γ-lactones. Three of these analogs were converted to the corresponding by γ-hydroxy-γ-lactams lactamization with isobutylamine and propylamine. Further dehydration of γ-hydroxy-γ-lactams resulted in the formation of (Z) and (E)-γ-alkylidene-γ-lactams. characterized by IR spectroscopy, All H and the synthesized compounds were 13 C NMR spectroscopy, COSY and HETCOR bidimensional techniques and mass spectrometry. NOEDIF experiments to determine the geometry of the double bond of the γ-alkylidene-γ-lactam units. The cytotoxicity assay was performed with OVCAR-8, SF-295, HCT-116 and HL-60 cancer cell lines. The results showed that the γ-lactones are more active than the γ- lactams. The best effects were associated with lactone (5Z)-3,4-dichloro-5-(4- bromobenzilidene)furan-2(5H)-one (21) which was active against all tested cell lines. Particularly, the compound 21 presented CR 50 = 0.66 μg/mL against HL-60. In the inhibition assay of bacterial biofilm formation of Streptococcus mutans, the compounds did not show good activity. Exception to this generalization is the lactone (5Z)-3,4-dichloro-5-(4-trifluoromethylbenzylidene)furan-2(5H)-one (26) which presented IC 50 = 0,21 ± 0,05 μg/mL.

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