Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis
Autor(a) principal: | |
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Data de Publicação: | 2017 |
Tipo de documento: | Tese |
Idioma: | por |
Título da fonte: | Manancial - Repositório Digital da UFSM |
Texto Completo: | http://repositorio.ufsm.br/handle/1/12446 |
Resumo: | This work first describes the synthesis of the starting materials, the 1,2,4- and 1,3,4-oxadiazoles, from arylamidoximes and arylhydrazides derivatives, respectively. These two precursors were previously reacted with the 2-chloroacetyl chloride, and after cyclodehydration formed the desired heterocycles in satisfactory yields (10 examples, 67-99 %). The heterocyclic starting materials were submitted to aliphatic nucleophilic substitution reactions (SN2) against calcogenolates derived from arylic and alkylic disselenides and thiols. The selenolates were obtained in reducing medium of NaBH4 and anhydrous ethanol, whereas the thiolates were formed by treatment of thiols in basic medium of Et3N, so that the products from these substitutions were obtained in good yields (41 examples, 25-99 %). Some aspects of the methodologies employed were also studied, and some statements are possible, because when using tellurium don’t occurred the formation of the desired products, and also the formation of by-products unwanted. Secondly, the heterocyclic starting materials were re-subsumed to the SN2 reactions, but now, against potassium chalcogenocyanates (KSCN and KSeCN) in acetonitrile and the presence of an ammonium salt (TBAB), which aimed to catalyze reactions of aliphatic substitutions. The molecules from these reactions were obtained in excellent yields (12 examples, 69-92 %), which were subsequently submitted to the cycloaddition reactions (3+2) with NaN3, in a solution of toluene and Et3N.HCl, to form the respective 1H-tetrazoles (12 examples, 49-99 %). The products obtained contain, in the same molecule, the oxadiazolic, tetrazolic and chalcogen core. Chalcogencyanates and tetrazoles were further evaluated in vitro for their antioxidant properties by reducing the DPPH radical and Mo (VI) to Mo (V), so that two chalcogencyanates and one tetrazole presented good results for the phosphomolibidenium test. The cyclic voltammetry technique was also used to evaluate the redox potential of these compounds. Some compounds obtained in the first stage of this work are under evaluation of their antioxidant properties, but preliminary tests presented promising results for the molecules in question. |
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Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóisSynthesis and biological evaluation of chalcogen oxadiazoles and chalcogen tetrazolesOxadiazóisOrganocalcogêniosTetrazóisOxadiazolesOrganochalcogensTetrazolesCNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICAThis work first describes the synthesis of the starting materials, the 1,2,4- and 1,3,4-oxadiazoles, from arylamidoximes and arylhydrazides derivatives, respectively. These two precursors were previously reacted with the 2-chloroacetyl chloride, and after cyclodehydration formed the desired heterocycles in satisfactory yields (10 examples, 67-99 %). The heterocyclic starting materials were submitted to aliphatic nucleophilic substitution reactions (SN2) against calcogenolates derived from arylic and alkylic disselenides and thiols. The selenolates were obtained in reducing medium of NaBH4 and anhydrous ethanol, whereas the thiolates were formed by treatment of thiols in basic medium of Et3N, so that the products from these substitutions were obtained in good yields (41 examples, 25-99 %). Some aspects of the methodologies employed were also studied, and some statements are possible, because when using tellurium don’t occurred the formation of the desired products, and also the formation of by-products unwanted. Secondly, the heterocyclic starting materials were re-subsumed to the SN2 reactions, but now, against potassium chalcogenocyanates (KSCN and KSeCN) in acetonitrile and the presence of an ammonium salt (TBAB), which aimed to catalyze reactions of aliphatic substitutions. The molecules from these reactions were obtained in excellent yields (12 examples, 69-92 %), which were subsequently submitted to the cycloaddition reactions (3+2) with NaN3, in a solution of toluene and Et3N.HCl, to form the respective 1H-tetrazoles (12 examples, 49-99 %). The products obtained contain, in the same molecule, the oxadiazolic, tetrazolic and chalcogen core. Chalcogencyanates and tetrazoles were further evaluated in vitro for their antioxidant properties by reducing the DPPH radical and Mo (VI) to Mo (V), so that two chalcogencyanates and one tetrazole presented good results for the phosphomolibidenium test. The cyclic voltammetry technique was also used to evaluate the redox potential of these compounds. Some compounds obtained in the first stage of this work are under evaluation of their antioxidant properties, but preliminary tests presented promising results for the molecules in question.Este trabalho descreve, inicialmente, a síntese dos materiais de partida, os 1,2,4- e 1,3,4-oxadiazóis, derivados de arilamidoximas e arilhidrazidas, respectivamente. Estes dois precursores reagiram previamente com o cloreto de 2-cloroacetila e após ciclodesidratação formaram os heterociclos desejados em rendimentos satisfatórios (10 exemplos, 67-99%). Os materiais de partida heterocíclicos foram submetidos às reações de substituição nucleofílica alifática (SN2) frente aos calcogenolatos derivados de disselenetos e tióis arílicos e alquílicos. Os selenolatos foram obtidos em meio redutor de NaBH4 e etanol anidro, já os tiolatos formam-se pelo tratamento de tióis em meio básico de Et3N, de modo que os produtos provenientes destas substituições foram obtidos em bons rendimentos (41 exemplos, 25-99%). Foram ainda, estudados alguns aspectos das metodologias empregadas, e algumas afirmações são possíveis, pois quando se utilizaram reagentes de telúrio não ocorreu a formação dos produtos desejados, e ainda se constatando a formação de subprodutos indesejados. Em um segundo momento, os materiais de partida heterocíclicos foram submetidos novamente às reações SN2, porém agora frente à calcogenocianatos de potássio (KSCN e KSeCN), em acetonitrila e na presença de um sal de amônio (TBAB), que teve como finalidade catalisar as reações de substituições alifáticas. As moléculas provenientes destas reações foram obtidas em excelentes rendimentos (12 exemplos, 69-92%), sendo que estes foram posteriormente submetidos às reações de cicloadição (3+2) com NaN3, em uma solução de tolueno e Et3N.HCl, formando os respectivos 1H-tetrazóis (12 exemplos, 49-99%). Os produtos obtidos contêm, em uma mesma molécula, os núcleos oxadiazólico, tetrazólico e calcogênio. Os calcogenocianatos e os tetrazóis foram ainda submetidos à avaliação de suas propriedades antioxidantes in vitro, por meio da redução do radical DPPH e do Mo (VI) à Mo (V), de forma que dentre os compostos avaliados, dois calcogenocianatos e um tetrazol exibiram bons resultados para o teste de fosfomolibidênio. Foi ainda utilizada a técnica de voltametria cíclica com o intuito de avaliar o potencial redox desses compostos. Alguns compostos obtidos, na primeira etapa deste trabalho, estão sob avaliação de suas propriedades antioxidantes, porém testes preliminares apresentaram resultados promissores para as moléculas em questão.Universidade Federal de Santa MariaBrasilQuímicaUFSMPrograma de Pós-Graduação em QuímicaCentro de Ciências Naturais e ExatasDornelles, Lucianohttp://lattes.cnpq.br/7629319262073140Braga, Antonio Luizhttp://lattes.cnpq.br/0314009951286457Fantinel, Leonardohttp://lattes.cnpq.br/3934644027018397Ilha, Viniciushttp://lattes.cnpq.br/3882671719676564Rodrigues, Oscar Endrigo Dorneleshttp://lattes.cnpq.br/6536519955416085Sauer, André Carpes2018-02-16T11:01:19Z2018-02-16T11:01:19Z2017-02-24info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisapplication/pdfhttp://repositorio.ufsm.br/handle/1/12446porAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccessreponame:Manancial - Repositório Digital da UFSMinstname:Universidade Federal de Santa Maria (UFSM)instacron:UFSM2018-02-16T11:01:19Zoai:repositorio.ufsm.br:1/12446Biblioteca Digital de Teses e Dissertaçõeshttps://repositorio.ufsm.br/ONGhttps://repositorio.ufsm.br/oai/requestatendimento.sib@ufsm.br||tedebc@gmail.comopendoar:2018-02-16T11:01:19Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM)false |
dc.title.none.fl_str_mv |
Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis Synthesis and biological evaluation of chalcogen oxadiazoles and chalcogen tetrazoles |
title |
Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis |
spellingShingle |
Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis Sauer, André Carpes Oxadiazóis Organocalcogênios Tetrazóis Oxadiazoles Organochalcogens Tetrazoles CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA |
title_short |
Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis |
title_full |
Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis |
title_fullStr |
Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis |
title_full_unstemmed |
Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis |
title_sort |
Síntese e avaliação biológica de calcogeno-oxadiazóis e calcogenotetrazóis |
author |
Sauer, André Carpes |
author_facet |
Sauer, André Carpes |
author_role |
author |
dc.contributor.none.fl_str_mv |
Dornelles, Luciano http://lattes.cnpq.br/7629319262073140 Braga, Antonio Luiz http://lattes.cnpq.br/0314009951286457 Fantinel, Leonardo http://lattes.cnpq.br/3934644027018397 Ilha, Vinicius http://lattes.cnpq.br/3882671719676564 Rodrigues, Oscar Endrigo Dorneles http://lattes.cnpq.br/6536519955416085 |
dc.contributor.author.fl_str_mv |
Sauer, André Carpes |
dc.subject.por.fl_str_mv |
Oxadiazóis Organocalcogênios Tetrazóis Oxadiazoles Organochalcogens Tetrazoles CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA |
topic |
Oxadiazóis Organocalcogênios Tetrazóis Oxadiazoles Organochalcogens Tetrazoles CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA |
description |
This work first describes the synthesis of the starting materials, the 1,2,4- and 1,3,4-oxadiazoles, from arylamidoximes and arylhydrazides derivatives, respectively. These two precursors were previously reacted with the 2-chloroacetyl chloride, and after cyclodehydration formed the desired heterocycles in satisfactory yields (10 examples, 67-99 %). The heterocyclic starting materials were submitted to aliphatic nucleophilic substitution reactions (SN2) against calcogenolates derived from arylic and alkylic disselenides and thiols. The selenolates were obtained in reducing medium of NaBH4 and anhydrous ethanol, whereas the thiolates were formed by treatment of thiols in basic medium of Et3N, so that the products from these substitutions were obtained in good yields (41 examples, 25-99 %). Some aspects of the methodologies employed were also studied, and some statements are possible, because when using tellurium don’t occurred the formation of the desired products, and also the formation of by-products unwanted. Secondly, the heterocyclic starting materials were re-subsumed to the SN2 reactions, but now, against potassium chalcogenocyanates (KSCN and KSeCN) in acetonitrile and the presence of an ammonium salt (TBAB), which aimed to catalyze reactions of aliphatic substitutions. The molecules from these reactions were obtained in excellent yields (12 examples, 69-92 %), which were subsequently submitted to the cycloaddition reactions (3+2) with NaN3, in a solution of toluene and Et3N.HCl, to form the respective 1H-tetrazoles (12 examples, 49-99 %). The products obtained contain, in the same molecule, the oxadiazolic, tetrazolic and chalcogen core. Chalcogencyanates and tetrazoles were further evaluated in vitro for their antioxidant properties by reducing the DPPH radical and Mo (VI) to Mo (V), so that two chalcogencyanates and one tetrazole presented good results for the phosphomolibidenium test. The cyclic voltammetry technique was also used to evaluate the redox potential of these compounds. Some compounds obtained in the first stage of this work are under evaluation of their antioxidant properties, but preliminary tests presented promising results for the molecules in question. |
publishDate |
2017 |
dc.date.none.fl_str_mv |
2017-02-24 2018-02-16T11:01:19Z 2018-02-16T11:01:19Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
format |
doctoralThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://repositorio.ufsm.br/handle/1/12446 |
url |
http://repositorio.ufsm.br/handle/1/12446 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Química UFSM Programa de Pós-Graduação em Química Centro de Ciências Naturais e Exatas |
publisher.none.fl_str_mv |
Universidade Federal de Santa Maria Brasil Química UFSM Programa de Pós-Graduação em Química Centro de Ciências Naturais e Exatas |
dc.source.none.fl_str_mv |
reponame:Manancial - Repositório Digital da UFSM instname:Universidade Federal de Santa Maria (UFSM) instacron:UFSM |
instname_str |
Universidade Federal de Santa Maria (UFSM) |
instacron_str |
UFSM |
institution |
UFSM |
reponame_str |
Manancial - Repositório Digital da UFSM |
collection |
Manancial - Repositório Digital da UFSM |
repository.name.fl_str_mv |
Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM) |
repository.mail.fl_str_mv |
atendimento.sib@ufsm.br||tedebc@gmail.com |
_version_ |
1805922131873103872 |