Design, synthesis, and in vitro evaluation of novel triazole analogues featuring isoxazole moieties as antifungal agents

Abstract

In order to develop novel antifungal agents, based on our previous work, a series of (2R,3R)-3-((3-substitutied-isoxazol-5-yl)methoxy)-2-(2,4-difluorophenyl)-1-(1H-1,2,4-triazol-1-yl) butan-2-ol (a1-a26) were designed and synthesized. All of the compounds exhibited good in vitro antifungal activities against eight human pathogenic fungi. Among them, compound a6 showed excellent inhibitory activity against Candida albicans and Candida parasilosis with MIC₈₀ values of 0.0313 μg/mL. In addition, compounds a6, a9, a12, a13 and a14 exhibited moderate inhibitory activities against fluconazole-resistant isolates with MIC₈₀ values ranging from 8 μg/mL to 16 μg/mL. Furthermore, compounds a6, a12 and a23 exhibited low inhibition profiles for CYP3A4. Clear SARs were analyzed, and the molecular docking experiment was carried out to further investigate the relationship between a6 and the target enzyme CYP51.

Keywords: Antifungal activity; Structure-activity relationship; Synthesis; Triazole.