Síntese de cumarinas e avaliação das atividades: larvicida, antimicrobiana e antioxidante

Abstract

Coumarin is a heterocyclic organic compound belonging to the benzopyrone class and of natural origin that stands out for its versatility and a wide range of biological applications. Among them, the use of coumarins as larvicides presents itself as an alternative to conventional methods of controlling mosquitoes such as Aedes aegypti. In addition, several compounds of natural origin have been studied as natural antimicrobial and antioxidant agents, including coumarins. In the present work, a series of coumarin derivatives were synthesized and submitted to evaluation for their larvicidal, antifungal and antioxidant activity. In the larvicidal evaluation, an in silico study was performed using enzymes homologous to AChE and GSTs. Compounds A1 and A3 presented the best score values for the enzymes AChE and GST, respectively. In the in vivo application, the bioassays were performed under a qualitative approach, using fourth instar larvae. The results of the larvicidal evaluation indicate that only derivative C3 has potential as a larvicidal. In addition, the synthesized coumarin derivatives were evaluated for their fungicidal activity, with only derivative A1 showing fungistatic activity against C. albicans. Regarding their activity against C. neoformans, derivatives A1 and A3 were classified as fungicidal at concentrations of 400 and 200 μg, with derivative C1 showing fungistatic behavior at a concentration of 400 μg. Finally, the coumarin derivatives were evaluated for their antioxidant activity; in the DPPH assay, only derivatives A3 and C3 showed activity, with IC50 (μM) of 171.76 ± 1.94 and 7.47 ± 0.22, respectively. In the SOD assay, derivative C3 showed activity similar to Quercetin, with IC50 (μM) of 55.26 ± 1.84. For the HOCl analysis, derivative A2 presented the best result, with IC50 (µM) of 35.34 ± 0.04.