Licenciatura em Química (Sede)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/26
Siglas das Coleções:
APP - Artigo Publicado em Periódico
TAE - Trabalho Apresentado em Evento
TCC - Trabalho de Conclusão de Curso
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7 resultados
Resultados da Pesquisa
Item Atividade antimicrobiana de análogos da piperina(2018-08-02) Bezerra, Leonardo Alexandre Barros; Ramos, Clécio Souza; http://lattes.cnpq.br/3782004073843685; http://lattes.cnpq.br/3961756201958567The structural modification of natural compounds is of significant importance for medicinal chemistry, from 1981 to 2014 1328 medicines were approved for commercialization, of which 51.5% are of natural origin and 26.8% are derived from phytochemicals. An example is the natural amide piperine, which is the target of several biological investigations, and which has demonstrated the potential to act as a precursor to new compounds with application in the modulation of biological phenomena with the 1,2,4 oxadiazole nucleus, which are a class of heterocyclic that exhibit a range of biological activities and that can be used for the synthesis of potential microbial agents. This work aims to report the extraction of piperine by microwave. Reflux hydrolysis of piperine to obtain piperinic acid in moderate yields. Obtaining the ethyl piperininate esters and 3,4 methylenedioxy ethyl cinnamate with excellent yields. The synthesis of amidoximes using the conventional methodology of stirring with hydroxylamine hydrochloride, sodium carbonate and the corresponding nitriles with the substituents (p-nitro, p-toluyl, m-toluyl, benzo, piperonyl, 4-pyridine) in yields of 37% -98%. Using the methodology of synthesis of oxadiazole by microwave using ethyl cyano acetate esters with piperonylamidoxime, ethyl ester 3,4-methylenedioxy cinnamate with 4-pyridine and p-toluyl amidoxime in the presence of K2CO3 and DMF. All oxadiazol precursors were elucidated by IV and the 1,2,4-oxadiazoles synthesized characterized by 1H and 13C NMR. Some compounds were tested bactericidal activities, where the 1,2,4-oxadiazoles presented excellent results against Staphylococcus aureus and Klebsiella pneumoniae and one of the compounds presented luminescent activity a little reported in the 1,2,4 oxadiazoles.Item Síntese e caracterização de 2-(3-aril-1,2,4-oxadiazol-5-il)-(1E,3E)-penta-1,3-dien-1-ila(2024-03-07) Silva, Juliana Carolina do Nascimento; Freitas Filho, João Rufino de; http://lattes.cnpq.br/9252404584350850; http://lattes.cnpq.br/62314822898372301,2,4-oxadiazoles are heterocyclic compounds containing two nitrogen atoms, one oxygen atom and two double bonds in their structure and due to their low aromaticity they are called a conjugated system. Due to its notable importance of its biological properties such as: anti-inflammatory, anti-asthmatic, anti-cancer, anti-tumor, among others. In this work, the synthesis and characterization of 1,2,4-oxadiazoles from amidoximes and ethyl sorbate are described. The approach adopted was qualitative and experimental. Characterization was carried out by infrared spectroscopy and ¹H and ¹³C nuclear magnetic resonance. The results revealed that the arylamidoximes obtained by the stirring method for 24 hours showed good yields, ranging from 75% to 90%. Ethyl sorbate prepared by Fischer esterification showed a yield of 82%. However, the 1,2,4-oxadiazoles obtained by the superbase method showed yields between 45% and 50%, due to the formation of byproducts with similar polarity to the compound of interest.Item Síntese de 1H-1,2,3-triazol glicopiranosídeos análogos de nucleosídeos com potencial atividade antiviral(2021-12-09) Silva, Carla Jasmine Oliveira e; Oliveira, Ronaldo Nascimento de; http://lattes.cnpq.br/9071551767043294; http://lattes.cnpq.br/6278050350925332In this work, new nucleoside analogues containing the heterocyclics 1,2,3-triazol and pyrimidine conjugated with glycopyranosides were synthesized. Initially, the construction of our first synthetic block was carried out: the [beta]-azido-glycosides 3a-c, from three subsequent steps. The acetylation reaction of the carbohydrates D-(+)-Glucose, D-(+)-Galactose and L-(+)-Arabinose provided the O-acetyl-glycosides 1a-c, which were used in the next step with a solution 33 % HBr/AcOH to obtain [alfa]-bromo-glycosides 2a-c. Finally, we continued with the azidation reaction that formed the [beta]-azido-glycosides with moderate yields of 49% (3a) and 55% (3b) after crystallization in dichloromethane/ethanol (1:1); and 55% (3b) and 45% (3c) after purification by column chromatography (hexane/ethyl acetate, 8:2). The second synthetic block was prepared from the reaction of the nucleotidic bases, uracil and fluorouracil, with the propargyl bromide which provided the N1-,N3-bis-alkylated pyrimidine bases 4a-b with yields of 88% and 96%. Thus, the triazole nuclei were obtained through the copper-catalyzed 1,3-dipolar cycloaddition reaction between [beta]-azido-glycosides 3a-c and N1-,N3-bis-alkylated pyrimidine bases 4a-c. The disubstituted 1,2,3-triazole derivatives 5a-i were synthesized in excellent yields between 82-99%, and with the reaction time reduced to 1 hour compared to the literature, using 20 mol% of Cu(I) and 20 mol% Et3N.Item Síntese para obtenção do 3,7-dimetóxikaempferol visando à atividade leishmanicida(2020-10-20) Oliveira, Arthur Vinicius Teixeira de; Camara, Celso de Amorim; http://lattes.cnpq.br/4500025814149366; http://lattes.cnpq.br/3130800162465676Flavonoids are a class of substance widely distributed in the plant kingdom and are found in stems, fruits, flowers etc. Numerous studies have been carried out to deepen the knowledge of the biological activity of flavonoids, some of which have been reported as antimicrobial, anti-inflammatory and antiviral activities. The present work aims to characterize methoxylated and benzylated derivatives of naringenin (9) in addition to testing protective reactions for future prototypes of leishmanicidal drugs, through changes in flavonoids. In this work, (9) was used as starting material for future reactions one of which being the methylation reaction regioselective to obtain 7-methoxy-naringenin, using dimethyl sulfate and potassium carbonate in acetone at room temperature, yielding 72%, and then the product formed is subjected to a protection reaction using benzyl bromide, however under the conditions tested the opening of ring C occurred , it was necessary to test other means of protection using silicon reagents and cyclization alternatives in an attempt to supply the desired products. The products were characterized by the usual methods in the literature and available in the research group, such as NMR, infrared and melting point.Item Síntese, caracterização e atividades biológicas de 1,2,4-oxadiazóis(2020-10-22) Silva, André Ricardo França da; Freitas Filho, João Rufino de; http://lattes.cnpq.br/9252404584350850; http://lattes.cnpq.br/6873023837824366Item Síntese de 2-aminoalquil-3-alquenil-1,4-naftoquinona funcionalizadas como matérias-primas na obtenção de novas moléculas bioativas(2022-06-07) Silva, Karolinny Gomes da; Camara, Celso de Amorim; http://lattes.cnpq.br/4500025814149366; http://lattes.cnpq.br/7894875948237128Quinones represent a large and varied family of metabolites of natural distribution. The interest in these substances has been intensified in recent years due to their pharmacological importance. The main interest in quinones comes from their capacity to induce oxidative stress in cells. This stress can also result from the action of many toxic environmental agents on living beings, such as gamma and ultraviolet radiation, ozone, and automobile pollutants in the air, as well as from certain substances in the food chain and from smoking. Natural and synthetic, quinones are substances known to possess potent and varied types of biological activities such as antitumor, molluscicidal, leishmanicidal, anti-inflammatory, antifungal, trypanocidal, antiprotozoal and inhibitors of the reverse transcriptase enzyme of the HIV-1 virus. The present work aims to establish a relationship between natural quinones and, by means of organic synthesis, obtain organic derivatives that possess biological activity.Item Modularidade aplicada à síntese de compostos bioativos(2022-06-06) Lima, Danielle Assis de Albuquerque; Nascimento, André Augusto Pimentel Liesen; http://lattes.cnpq.br/8040722729889752; http://lattes.cnpq.br/4620645760514341The synthesis of bioactive compounds is characterized by the high number of steps to obtain its final product, refining it to the maximum so that its biological activity demonstrates more efficiency, consequently making it a time-consuming process, and because of this, the idea of synthesis modular has become strongly promising. Modular Reactions have taken up a large space in the scope of organic synthesis, for bringing innovations and ways to speed up the obtaining of bioactive compounds for pharmacological use. Firstly, modular reactions draw attention because they are reactions that take advantage of the concept of modularity, which can be summarized in the idea of using so-called “building blocks”, where different compounds are used, participating in varied combinations, having as Consequently, the reduction in the number of steps and, on the other hand, presenting the possibility of increasing the production of analogues of the researched product in a timely manner, in addition to the production of new products with interesting biological properties. This synthesis strategy still gains a lot of space for presenting the possibility of automating the reactions, where the idea of automation is centered on increasing the productivity and the speed with which the compounds will be formed, being able to be done from a script to obtain the products, to computer programming and automation to carry out the syntheses. The implementation of modularity carries with it scientific innovations that help in the growing demand for new drugs.