Abstract
The endophytic fungus Mycosphaerella sp. (UFMGCB2032) was isolated from the healthy leaves of Eugenia bimarginata, a plant from the Brazilian savanna. Two novel usnic acid derivatives, mycousfuranine (1) and mycousnicdiol (2), were isolated from the ethyl acetate extract, and their structure was elucidated by NMR and MS analyses. Compounds 1 and 2 exhibited moderate antifungal activities against Cryptococcus neoformans and Cryptococcus gattii, each with minimum inhibitory concentration values of 50.0 μg/mL and 250.0 μg/mL, respectively.
Acknowledgments
We would like to thank the “Conselho Nacional de Desenvolvimento Cientifico e Tecnológico” (CNPq) for their financial support and scholarship award. This work was also supported in part by a grant from “Fundação de Amparo à Pesquisa do Estado de Minas Gerais” (FAPEMIG). The authors would also like to thank the staff (Charles da Silva Amaral and ElianeGonçalvesCarvalho) of the Program of Technological Development in Tools for Health PDTIS-FIOCRUZ, RPT13A platform for allowing us the use of its facilities.
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Supplementary Material
The online version of this article offers supplementary material (https://doi.org/10.1515/znc-2017-0162).
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