Background:
Previous publications show that the addition of a phenolic antioxidant to
an antifungal agent, considerably enhances the antifungal activity.
Objective:
Synthesis of novel compounds combining phenolic units with linear or cyclic nitrogencontaining
organic molecules with antioxidant/antifungal activity using methodologies previously
developed in the group.
Methods:
Several N- [1,2-dicyano-2- (arylidenamino) vinyl]-O-alkylformamidoximes 3 were synthesized
and cyclized to 4,5-dicyano-N- (N´-alcoxyformimidoyl)-2-arylimidazoles 4 upon reflux in
DMF, in the presence of manganese dioxide or to 6-cyano-8-arylpurines 5 when the reagent was
refluxed in acetonitrile with an excess of triethylamine. These compounds were tested for their antioxidant
activity by cyclic voltammetry, DPPH radical (DPPH•) assay and deoxyribose degradation
assay. The minimum inhibitory concentration (MIC) of all compounds was evaluated against
two yeast species, Saccharomyces cerevisiae and Candida albicans, and against bacteria Bacillus
subtilis (Gram-positive) and Escherichia coli (Gram negative). Their cytotoxicity was evaluated in
fibroblasts.
Results:
Among the synthetised compounds, five presented higher antioxidant activity than reference
antioxidant Trolox and from these compounds, four presented antifungal activity without
toxic effects in fibroblasts and bacteria.
Conclusion:
Four novel compounds presented dual antioxidant/antifungal activity at concentrations
that are not toxic to bacteria and fibroblasts. The active molecules can be used as an inspiration
for further studies in this area.