Anti-Candida, anti-enzyme activity and cytotoxicity of 3,5-diaryl-4,5-dihydro-1H-pyrazole-1-carboximidamides.

Because of the need for more effective and less harmful antifungal therapies, and interest in the synthesis of new carboximidamides, the goal of this study was to determine the antifungal and anti-enzyme activities of some new pyrazole carboximidamides and their cytotoxicity. For this purpose, tests were performed to evaluate: minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC); production of proteinases and phospholipase, and cytotoxicity of the extracts. Data were analyzed by ANOVA and Tukey Tests (α = 5%). The results were: MIC and MFC ≥ 62.5 μg/mL (C. albicans, C. parapsilosis, C. famata, C. glabrata, and Rhodotorula mucillaginosa) and MIC and MFC ≥ 15.6 μg/mL (C. lipolytica). The values of proteinase and phospholipase (Pz) of C. albicans before and after exposure to the compounds were: 0.6 (±0.024) and 0.2 (±0.022) and 0.9 (±0.074) and 0.3 (±0.04), respectively. These proteinase results were not significant (p = 0.69), but those of phospholipase were (p = 0.01), and 15.6 μg/mL was the most effective concentration. The cytotoxicity means were similar among the tests (p = 0.32). These compounds could be useful as templates for further development through modification or derivatization to design more potent antifungal agents. Data from this study provide evidence that these new pyrazole formulations could be an alternative source for the treatment of fungal infections caused by Candida. However, a specific study on the safety and efficacy of these in vivo and clinical trials is still needed, in order to evaluate the practical relevance of the in vitro results.