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Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2021-05-12T13:54:33Z No. of bitstreams: 1 2018 - Carla Cristina da Silva.pdf: 2750023 bytes, checksum: e8fe906b016884629b9bd10e5c1cca82 (MD5) Made available in DSpace on 2021-05-12T13:54:33Z (GMT). No. of bitstreams: 1 2018 - Carla Cristina da Silva.pdf: 2750023 bytes, checksum: e8fe906b016884629b9bd10e5c1cca82 (MD5) Previous issue date: 2018-08-15 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior Bacteria are unicellular beings that can be found alone or in colonies. In the 19th century, scientists began to associate some diseases with certain species of bacteria. Researchers have since sought compounds capable of acting on these species of bacteria and minimizing the effects of infectious processes caused by some of them and considered serious. Several classes of compounds have been discovered throughout the 20th century capable of inhibiting the growth or even causing the death of pathogenic bacteria. However, the large capacity of these mutated bacteria led to the emergence of strains resistant to these substances. Thus, the development of new compounds with antibacterial potential is necessary. Several research groups have developed new prototypes to antibacterial drugs from natural products that already have satisfactory biological activity, such as quinones. In this work 11 compounds were synthesized from the reaction of 1,4-naphthoquinone and 11 different amines. The compounds obtained were characterized by infrared and 1H and 13C NMR spectroscopy. Six compounds were tested for Minimum Inhibitory Concentration against 4 strains of Gram-positive bacteria and 5 strains of Gram-negative bacteria. Of the compounds tested, three were active against various bacteria at concentrations ranging from 31.2 to 250 ?g / ml. For the compounds that showed better antibacterial activity, the interaction with human serum albumin, a protein present in large numbers in the higher mammals and responsible for the transport of biologically active molecules, was tested. The Ksv and Ka values obtained indicate moderate interaction formation between the HSA and the compounds tested, ensuring satisfactory bioavailability of the compounds in the blood plasma. Thus, the results obtained in this work indicate that the synthesized 1,4-naphthoquinone amino derivatives can be used as potential antibacterial agents against some species of Gram-positive and Gram-negative bacteria. As bact?rias s?o seres unicelulares que podem ser encontradas sozinhas ou em col?nias. No s?culo XIX, cientistas come?aram a associar algumas doen?as ? determinadas esp?cies de bact?rias. Desde ent?o os pesquisadores buscam compostos capazes de atuarem sobre essas esp?cies de bact?rias e minimizar os efeitos de processos infecciosos causados por algumas delas e considerados graves. Foram descobertas diversas classes de compostos ao longo do s?culo XX capazes de inibir o crescimento ou at? mesmo de causar a morte de bact?rias patog?nicas. Por?m, a grande capacidade destas bact?rias de sofrer muta??o levou ao surgimento de cepas resistentes a estas subst?ncias. Assim, o desenvolvimento de novos compostos com potencial antibacteriano ? necess?rio. Diversos grupos de pesquisa tem desenvolvido novos prot?tipos ? f?rmacos antibacterianos a partir de produtos naturais que j? apresentam atividade biol?gica satisfat?ria, como as quinonas. Neste trabalho de disserta??o foram sintetizados 11 compostos a partir da rea??o da 1,4-naftoquinona e 11 aminas diferentes. Os compostos obtidos foram caracterizados por espectroscopia de infravermelho e RMN 1H e 13C. Foram ensaiados 6 compostos para determina??o da Concentra??o Inibit?ria M?nima frente a 4 cepas de bact?rias Gram-positivas e 5 cepas de bact?rias Gram-negativas. Dos compostos ensaiados, tr?s mostraram-se ativos contra diversas bact?rias, em concentra??es que variaram entre 31,2 e 250 ?g/mL. Para os compostos que apresentaram melhor atividade antibacteriana foi testada a intera??o com a soro albumina humana, prote?na presente em grande quantidade nos mam?feros superiores e respons?vel pelo transporte de mol?culas biologicamente ativas. Os valores de Ksv e Ka obtidos indicam forma??o de intera??o moderada entre a HSA e os compostos ensaiados, garantindo biodisponibilidade satisfat?ria dos compostos no plasma sangu?neo. Assim, os resultados obtidos neste trabalho indicam que os amino-derivados da 1,4-naftoquinona sintetizados podem ser utilizados como potenciais agentes antibacterianos contra algumas esp?cies de bact?rias Gram-positivas e Gram-negativas.