Resumo

Despite the widespread prophylactic use of agents with antifungal properties, infections caused by pathogenic fungi are causing increasing mortality and morbidity in a variety of immunocompromised patients. High recurrence has sparked growing concern among clinicians regarding the potential emergence of resistance among these opportunistic mycoses agents. Considering the need of more effective and less toxic drugs, associated to the large potential of thiophene-derived bioactive molecules to inhibit the growth of pathogenic fungi, we evaluated Candida, Cryptococcus and dermatophytes susceptibility, stocked in URM Culture Collection, against pure 2-[(3,4-dichloro-benzilidene)-amine]-5,6-diydro-4H-cyclopenta[b]tiophene-3-carbonitrile (5CNO5) and microemulsioned formulation. The minimal inhibitory concentration (MIC) were determined following the microdilution methods M27-A3 and M38-A2 indicated by the Clinical and Laboratory Standards Institute. Amphotericin B and fluconazole were used as controls drus. All isolates evaluated presented MIC to 5CNO5, which showed moderate or poor antifungal activity against Candida albicans, Candida krusei, Candida parapsilosis and Candida tropicalis isolates among 128-512 μg/mL, nevertheless presented MIC of 16 μg/mL against the dermatophytes Trichophyton mentagrophytes, Trichophyton rubrum and Epidermophyton flocossum and Cryptococcus isolates. The all isolates studied were resistant to 5CNO5 microemulsioned, except Cryptococcus neoformans URM 5711 that presented MIC of 8 μg/mL, a lower concentration that the molecule pure. This paper underscores the importance of the antifungal potential of thiophene derivates against Cryptococcus spp. as an alternative treatment against systemic cryptococosis. However, in vivo experiments are essential for future medical use.