Microwave-Assisted Synthesis of Novel Symmetric Bis-1,2,4-triazolin-3-ones as Potent Inhibitors of CYP51: An Antifungal Activity Study

摘要

Improvement of antifungal agents is a good solution to beat the drug-resistance problems. In this context, a series of novel bis-1,2,4-triazolin-3-ones (5i-t) were designed and synthesized by microwave irradiation (MWI), a convenient and efficient method. An effort was also made to get these bis-1,2,4- triazolin-3-ones (5i-t) by one-pot three-component reaction (3CR) using 3-aryl-5-methyl-1,3,4-oxadiazol-2(3H)-one (2a-b), formamide and dibromo reagent (4c-h) under microwave irradiation (MWI). In vitro antifungal activity was carried out against six pathogenic fungi. From the results it was observed that the newly synthesized bis-1,2,4-triazolin-3-ones (5i-t) have shown excellent activity against all the tested pathogenic fungi with least MIC values in the range of 0.80 μg/ml to 0.20 μg/ml. Particularly, in comparison with the reference drug Fluconazole and mono-1,2,4-triazolin-3-ones (3a-b) some of the bis-1,2,4- triazolin-3-ones (5i, 5j, 5m, 5p and 5r) have shown broad spectrum of antifungal activity. Further, the molecular docking study has been performed for all the tested compounds with 14α-demethylase (CYP51) as target enzyme and this study validated the experimental results. Thus, docking study has culminated in the identification of a new class of potent inhibitors of CYP51. The results provide significant information for the future design of more potent antifungal agents.