Study of a selected series of 3- and 4-arylcoumarins as antifungal agents against dermatophytic fungi: T. rubrum and T. mentagrophytes

The main etiological agents in dermatophytosis of human skin and nails are Trichophyton, in particular Trichophyton rubrum (T. rubrum) and Trichophyton mentagrophytes (T. mentagro- phytes). A new series of twenty-three 3- and 4-arylcoumarins was synthesized and the antifungal activities against clinical isolates of T. rubrum and T. mentagrophytes were evaluated. Sixteen out of twenty-three molecules exhibited antifungal activity against one or both fungi strains. In some cases, the activity against T. rubrum has been comparable to fluconazole, one of the standards, being 8-methoxy-3-(4’-nitrophenyl) coumarin (16) the best compound within this series (minimum inhibitory concentration, MIC=6.25 μg/mL). The preliminary structure-activity relationship study showed that the antifungal activity depends on the position and nature of the substitution patterns. The cytotoxicity of eleven compounds on D-384 (astrocytoma), A-549 (lung cancer) and RKO (colorectal cancer) cell lines was also performed. With the aim of deeply under- stand the potential of these molecules as hits to develop new drugs, the theoretical absorption, distribution, metabolism and excretion (ADME) properties of the active compounds were calculate