Antifungal activities of novel 1,2,3-benzotriazole derivatives synthesized by ultrasonic and solvent-free conditions

Objectives

To evaluate the antifungal activities of novel 1,2,3-benzotriazole derivatives synthesized by ultrasonic and solvent-free conditions.

Methods

Newer “1-(1H-benzo[d][1,2,3]triazole-1-carbonyl) derivatives” (5A–5P) were synthesized by using “1H–benzo[d][1,2,3]triazole” (1) as the starting material under ultrasonicated and solvent-free conditions. The resulting products were isolated and characterized by melting points and spectral studies. All the products were assayed for antifungal activity for various pathogenic fungi.

Results

Excellent antifungal activity was shown by derivative-5L against Candida albicans (MTCC – 3018) whereas other compounds have shown comparable activity. Except derivative-5P, all synthesized compounds have shown mild activity against Candida glabrata (MTCC – 3019). Towards Aspergillus niger (MTCC – 2638) and Aspergillus flavus (MTCC – 2737) most of the compounds were inactive and some were feebly active. All the synthesized derivatives were inactive against Saccharomyces cerevisiae (MTCC – 170). The Minimum Inhibitory Concentrations (MIC) of the most of the synthesized 1,2,3-benzotriazole derivatives for these fungi were found to be 62.5 μg/ml.

Conclusions

Some of the newer 1,2,3-benzotriazole derivatives synthesized under solvent-free and ultrasound irradiation with noteworthy advantages viz., shorter reaction times, operational simplicity, simple work-up, and eco-friendly nature, have shown antifungal activities against selected pathogenic strains. Attachment of phenyl or phenyl with electron withdrawing substituents to either nitrile or azo functional group can be attributed to the substantial antifungal activity of these benzotriazoles.