Tiossemicarbazonas e ditiocarbazatos contendo anel pirazolínico: obtenção, estudos de atividade tripanocida e de formação de complexos com gálio

• Main Author: Vanessa Fernandes Ferreira
• Other Authors: Victor Marcelo Deflon
• Language: Portuguese
• Published: Universidade de São Paulo 2015
• Subjects: anel pirazolínico; complexos de gálio; ditiocarbazatos; Tiossemicarbazonas; Dithiocarbazates; gallium complexes; pyrazoline ring; Thiosemicarbazones
• Online Access: http://www.teses.usp.br/teses/disponiveis/75/75135/tde-04122015-152422/

O presente trabalho consiste na síntese, caracterização e estudos de atividade tripanocida de doze compostos, sendo oito tiossemicarbazonas (TSCs) e quatro ditiocarbazatos (DTCs), contendo anel pirazolínico em suas estruturas, assim como no estudo da formação de complexos de um DTC com GaIII. As TSCs e os DTCs foram obtidos em reações de condensação envolvendo uma β-dicetona e uma tiossemicarbazida ou ditiocarbazato, respectivamente. A partir de 1-fenil-1,3-butanodiona (benzoilacetona) e 4-R-tiossemicarbazida, foram obtidas as TSCs de nome 5-hidroxi-3-metil-5-fenil-pirazolina-1-(4-R-tiossemicarbazona), identificados como H2bt, H2bmt, H2bet e H2bpt, com R = H, Me, Et e Ph, respectivamente. Mudando a β-dicetona para 4,4,4-trifluoro-1-fenil-1,3-butanodiona, foram obtidas as TSCs de nome 5-hidroxi-3-fenil-5-trifluorometil-pirazolina-1-(4-R-tiossemicarbazona), identificados como H2ft, H2fmt, H2fet e H2fpt, com R = H, Me, Et e Ph, respectivamente. De modo similar, os DTCs de nome 5-hidroxi-3-metil-5-fenil-pirazolina-1-(S-p-R-benzilditiocarbazato), H2bdtc e H2mbdtc, para R = H e OMe, respectivamente, foram obtidos a partir de benzoilacetona e S-p-R-benzilditiocarbazato, enquanto que os DTCs de nome 5-hidroxi-3-fenil-5-trifluorometil-pirazolina-1-(S-p-R-benzilditiocarbazato), H2fdtc e H2mfdtc, para R = H e OMe, respectivamente, formaram-se quando a 4,4,4-trifluoro-1-fenil-1,3-butanodiona foi a β-dicetona utilizada. Os compostos foram caracterizados por diversas técnicas, que incluíram análise elementar, espectroscopia na região do infravermelho (IV), espectrometria de massas, ressonância magnética nuclear de hidrogênio e flúor (RMN1H e 19F) e difração de raios X em monocristal. As TSCs e os DTCs foram avaliados quanto a suas atividades anti-T. cruzi e citotoxicidade frente a células de macrófagos J774, sendo possível avaliar as influências dos grupos periféricos substituintes. Nestes estudos, dois novos compostos, além do H2bdtc, cuja atividade é conhecida, se mostraram promissores, H2bt e H2bmt, apresentando valores de atividade tripanocida CC50try = 9,91 e 6,85 µM, respectivamente, para a cepa Y na forma tripomastigota do T. cruzi. Ambos foram superiores ao benzonidazol, utilizado como referência (CC50try = 10,6 µM). Os compostos também se mostraram seletivos, com CC50 > 100 µM para células de macrófago J774. Estudos de complexação com GaIII utilizando H2bdtc como agente complexante levaram a dois novos complexos, variando-se as condições reacionais, sendo um mononuclear, [Ga(bdtc)(Hbdtc)].CH3OH, e um dinuclear, [Ga2(bdtc)2(µOCH3)2].CH2Cl2, os quais foram caracterizados, tanto em solução quanto no estado sólido, tendo tido suas estruturas determinadas por difração de raios X em monocristal. Ambos apresentam centros de GaIII pentacoordenados, com grau de distorção diferenciado, entre uma geometria de coordenação bipiramidal trigonal e piramidal de base quadrada. Quando dianiônico, o bdtc2- coordenou-se O,N,S-tridentado, diferentemente da forma S,N-bidentada observa para o DTC, quando coordenado monoaniônico, como bdtc1-. === The present work describes the synthesis, structural characterization and trypanocidal activity studies of twelve compounds, eight thiosemicarbazones (TSCs) and four dithiocarbazates (DTCs) containing pyrazoline ring in their structures, as well as in the study of complex formation of a DTC with GaIII. The TSCs and DTCs were obtained from condensation reactions involving a & beta;-diketone and a dithiocarbazate or thiosemicarbazide, respectively. From 1-phenyl-1,3-butanedione (benzoylacetone) and 4-R-thiosemicarbazide were obtained TSCs the name 5-hydroxy-3-methyl-5-phenyl-pyrazoline-1-(4-R-thiosemicarbazone), identified as H2bt, H2bmt, H2bet and H2bpt, R = H, Me, Et, Ph, respectively. Changing the & beta;-diketone for 4,4,4-trifluoro-1-phenyl-1,3-butanedione result in TSCs the name 5-hydroxy-3-phenyl-5-trifluoromethyl-pyrazoline-1-(4-R-thiosemicarbazone), identified as H2ft, H2fmt, H2fet and H2fpt, R = H, Me, Et, Ph, respectively. Similarly, the DTCs with name 5-hydroxy-3-methyl-5-phenyl-pyrazoline-1-(S-p-R-benzyldithiocarbazate), H2bdtc and H2mbdtc to R = H and OMe, respectively, were obtained from benzoylacetone and S-p-R-benzyldithiocarbazate, while DTCs 5-hydroxy-3-phenyl-5-trifluoromethyl-pyrazoline-1-(S-p-R-benzyldithiocarbazate), H2fdtc and H2mfdtc to R = H and OMe, respectively, are formed with 4,4,4-trifluoro-1-phenyl-1,3-butanedione. The compounds were characterized by various techniques such as elemental analysis, infrared spectroscopy (IR), mass spectrometry, nuclear magnetic resonance of hydrogen and fluorine (1H and 19F NMR) and single crystals X-ray diffraction. The TSCs and DTCs were evaluated for their anti-T. cruzi activity and cytotoxicity against macrophage cells, making it possible to evaluate the effects of substituent peripheral groups. In these studies, other two new compounds than H2bdtc whose activity is known, were considered promising, H2bt and H2bmt, having superior activity, CC50try values 9.91 and 6.85 µM, respectively, compared with benznidazole used as reference (CC50try = 10.6 µM). The compounds also show selective with CC50> 100 µM for J774 macrophage cells. In the complexation studies with GaIII using H2bdtc it is possible to obtain two new complex, varying the reaction conditions, being a mononuclear, [Ga(bdtc)(Hbdtc)]·CH3OH, and other dinuclear [Ga2(bdtc)2(µ OCH3)2].CH2Cl2, which were characterized both in solution and in solid state, having their structures determined by single crystals X-ray diffraction. Both having GaIII pentacoordenate, with distortion of coordination geometry between trigonal bipyramidal and square pyramidal. When the ligand bdtc2- coordinated dianionic the form is O,N,S-tridentate, unlike the form S,N-bidentate was observed for the DTC when coordinated monoanionic as bdtc1-.The present work describes the synthesis, structural characterization and trypanocidal activity studies of twelve compounds, eight thiosemicarbazones (TSCs) and four dithiocarbazates (DTCs) containing pyrazoline ring in their structures, as well as in the study of complex formation of a DTC with GaIII. The TSCs and DTCs were obtained from condensation reactions involving a ?-diketone and a dithiocarbazate or thiosemicarbazide, respectively. From 1-phenyl-1,3-butanedione (benzoylacetone) and 4-R-thiosemicarbazide were obtained TSCs the name 5-hydroxy-3-methyl-5-phenyl-pyrazoline-1-(4-R-thiosemicarbazone), identified as H2bt, H2bmt, H2bet and H2bpt, R = H, Me, Et, Ph, respectively. Changing the ?-diketone for 4,4,4-trifluoro-1-phenyl-1,3-butanedione result in TSCs the name 5-hydroxy-3-phenyl-5-trifluoromethyl-pyrazoline-1-(4-R-thiosemicarbazone), identified as H2ft, H2fmt, H2fet and H2fpt, R = H, Me, Et, Ph, respectively. Similarly, the DTCs with name 5-hydroxy-3-methyl-5-phenyl-pyrazoline-1-(S-p-R-benzyldithiocarbazate), H2bdtc and H2mbdtc to R = H and OMe, respectively, were obtained from benzoylacetone and S-p-R-benzyldithiocarbazate, while DTCs 5-hydroxy-3-phenyl-5-trifluoromethyl-pyrazoline-1-(S-p-R-benzyldithiocarbazate), H2fdtc and H2mfdtc to R = H and OMe, respectively, are formed with 4,4,4-trifluoro-1-phenyl-1,3-butanedione. The compounds were characterized by various techniques such as elemental analysis, infrared spectroscopy (IR), mass spectrometry, nuclear magnetic resonance of hydrogen and fluorine (1H and 19F NMR) and single crystals X-ray diffraction. The TSCs and DTCs were evaluated for their anti-T. cruzi activity and cytotoxicity against macrophage cells, making it possible to evaluate the effects of substituent peripheral groups. In these studies, other two new compounds than H2bdtc whose activity is known, were considered promising, H2bt and H2bmt, having superior activity, CC50try values 9.91 and 6.85 µM, respectively, compared with benznidazole used as reference (CC50try = 10.6 µM). The compounds also show selective with CC50> 100 µM for J774 macrophage cells. In the complexation studies with GaIII using H2bdtc it is possible to obtain two new complex, varying the reaction conditions, being a mononuclear, [Ga(bdtc)(Hbdtc)]·CH3OH, and other dinuclear [Ga2(bdtc)2(?-OCH3)2]·CH2Cl2, which were characterized both in solution and in solid state, having their structures determined by single crystals X-ray diffraction. Both having GaIII pentacoordenate, with distortion of coordination geometry between trigonal bipyramidal and square pyramidal. When the ligand bdtc2- coordinated dianionic the form is O,N,S-tridentate, unlike the form S,N-bidentate was observed for the DTC when coordinated monoanionic as bdtc1-.