Derivados p-Cumaratos sintéticos: estudo antiparasitário, antimicrobiano, antienzimático e in silico

• Ano de defesa: 2022
• Autor(a) principal: Lopes, Susiany Pereira
• Tipo de documento: Tese
• Tipo de acesso: Acesso embargado
• Idioma: por
• Instituição de defesa: Universidade Federal da Paraíba; Brasil; Farmacologia; Programa de Pós-Graduação em Desenvolvimento e Inovação Tecnológica em Medicamentos; UFPB
• Palavras-chave em Português: Ácido p-cumárico; Trypanosoma cruzi; Leishmania braziliensis; Plasmodium falciparum; Candida; p-coumaric derivatives; CNPQ::CIENCIAS BIOLOGICAS::FARMACOLOGIA
• Link de acesso: https://repositorio.ufpb.br/jspui/handle/123456789/26318

p-Coumaric acid is a naturally abundant phenolic compound that has generated great interest among researchers in the discovery and development of new drugs, due to its beneficial effects against various pathologies. In the present study, the trypanocidal effect was tested on epimastigote and trypomastigote forms of T. cruzi, leishmanicidal activities on the amastigote form of L. braziliensis, antiplasmodic on P. falciparum, all using the microdilution technique in 96-well plates, in addition to the inhibitory activity of AChE and BChE enzymes using the spectrophotometric method and antifungal activity evaluating MIC and CFM as well as the mechanisms of action of derivatives. Among the tweunty three derivates, which were obtained via Fischer esterification, Mitsunobu reaction and SN2 nucleophilic substitution reactions with alkyl and aryl halides, eight compounds unpublished in the literature were identified by infrared and ¹H and ¹³C magnetic resonance spectroscopic methods, as well as high resolution mass spectrometry. Of these, pentyl p-coumarate (7) showed the best trypanocidal activity against epimastigote (5.16 ± 1.28 μM) and trypomastigote (61.63 ± 28.59 μM) forms. Flow cytometry analysis revealed an increase in the percentage of 7-AAD, an increase in reactive oxygen species and a loss of mitochondrial membrane potential, indicating cell death by necrosis. In this mechanism wich was confirmed by scanning electron microscopy, a loss of cellular integrity was observed. The molecular docking data indicated that compound 7 potentially acts through two mechanisms of action, via links with aldo-keto reductase (AKR) or via cruzain (CZ), which is one of the main developmental enzyme of T. cruzi. The results indicate that van der Waals interactions between ligand and receptors favor hydrophobic interactions with the phenolic and aliphatic parts of the ligand. In addition, hexyl p-coumarate (9) (4.14 ± 0.55 μg/mL; SI=2.72) showed the best leishmanicidal activity against the L. braziliensis amastigotes form. The molecular docking results of compound 9 indicate that ALDH, MPK4 and TOP2 are potentially promising targets to guide future investigations into the possible mechanisms of action. Among the compounds analyzed against P. falciparum, methyl p-coumarate (1) (64.59 ± 2.89 μg/mL; SI= 0.1) showed activity against the other derivatives. Regarding the inhibitory activity against butyrylcholinesterase, three derivates showed bioactivity: 4-chlorobenzyl p-coumarate (14) (75.17 ± 1.81; IC50=19.08 ± 0.70 μM), 4-bromobenzyl p-coumarate (15) (76.09 ± 2.16; IC50=22.22 ± 1.50 μM) and naphthalene p-coumarate (19) (65.39 ± 3.88; IC50=22.69 ± 2.15 μM). In the evaluation of antifungal activity, compounds 9 (62.90; 31.45 and 125.85 μM) and 14 (27.05; 54.09 and 54.09 μM) were bioactive against Candida albicans, Candida krusei e Candida tropicalis. Thus, the presente study demonstrates that p-coumaric acid derivatives are promising compounds for the search for new drug candidates against diferente pathogens and neurological disorders.