Thiosemicarbazones and thiazoles antifungal activity against Sporothrix and first Sporothrix mexicana from human sporotrichosis in Brazil.

AIM: In this study, we evaluated the antifungal potential of halogenated and nitro thiosemicarbazones and phenoxy-hydrazone-thiazole derivatives against Sporothrix clinical strains.

METHODS

Antifungal activity of 10 compounds was assessed by broth microdilution. Cytotoxicity of the compounds was determined. Structure-activity relationship studies were performed.

RESULTS

2-(3-(3-Bromophenoxi)-2-butanilideno)thiosemicarbazone (named DT 06) and 2-(3-(4-Nitrophenoxi)-2-butanilideno)thiosemicarbazone (named DT 24) showed antifungal activity with MICs from 16 to 128 μg.mL-1. All compounds showed low toxicity on splenocytes and macrophages cell lines.

CONCLUSION

Molecular hybrids of halogenated and nitro thiosemicarbazones and phenoxyhydrazone-thiazoles have proved to be promising compounds with low toxicity against Sporothrix clinical isolates, especially derivatives containing the thiosemicarbazone class. Furthermore, this study identified the first Sporothrix mexicana related to human sporotrichosis in Brazil. It is noteworthy that this environmental isolate was transmitted to the patient by zoonotic route.