Banca de DEFESA: RICARTE TAVARES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : RICARTE TAVARES
DATE: 24/02/2025
TIME: 14:00
LOCAL: Departamento de Química
TITLE:

SYNTHESIS AND CHARACTERIZATION OF 1,2,4-OXADIAZOLES AND 2,3-UNSATURATED O-GLYCOSIDE TARGETING COMPOUNDS WITH BIOLOGICAL ACTIVITIES

KEY WORDS:

2,3-unsaturated O-Glycosides, 1,2,4-oxadiazole, amidoximes, Drugs.

PAGES: 169
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Síntese Orgânica
SUMMARY:

The search for new bioactive compounds has been an important strategy in the discovery of effective antimicrobial agents, especially in light of the growing problem of bacterial resistance. In this context, this study aims to synthesize, characterize, and evaluate the antimicrobial activity of 1,2,4-oxadiazole derivatives and 2,3-unsaturated O-glycosides, using molecular hybridization strategies to enhance pharmacological properties. For this purpose, the starting reagents were initially obtained. For the synthesis of 1,2,4-oxadiazoles, amidoximes and ethyl oleate were prepared. Ethyl oleate was synthesized through the Fischer esterification reaction of oleic acid, while amidoximes 47a-h were obtained using the classical method in a basic medium, resulting in varying yields. The conversion to 1,2,4-oxadiazoles (46a-h) was performed under microwave irradiation, yielding different results. Compounds 46a-e were subjected to antimicrobial activity tests against two different bacterial strains, Pseudomonas aeruginosa and Enterococcus faecalis. However, the results indicated low antimicrobial activity. To better understand the properties of these molecules, molecular docking studies and ADMET property predictions were conducted. Regarding O-glycosides, these were synthesized through the Ferrier rearrangement, using tri-O-acetyl-D-glucal as the glycone, reacting with oleic alcohol, phytol alcohol, ethyl 4-hydroxybenzoate, and cinnamyl alcohol. This approach enabled the production of 2,3-unsaturated O-glycosides (49a, 50a, 51a, 50, 51), which were subsequently subjected to basic hydrolysis, yielding the deacetylated products (49b, 50b, 51b). The structural characterization of the synthesized compounds was carried out using infrared spectroscopy and nuclear magnetic resonance (¹H and ¹³C NMR), confirming their structures.

COMMITTEE MEMBERS:
Presidente - JOAO RUFINO DE FREITAS FILHO
Interno - MARCILIO MARTINS DE MORAES
Externo ao Programa - 3022573 - JUCLEITON JOSE RUFINO DE FREITAS - UFRPEExterno à Instituição - JADSON DE FARIAS SILVA - UFRPE
Externa à Instituição - LIDIANE MACEDO ALVES DE LIMA - UFRPE