Investigation of pyrazole and tetrazole derivatives containing 3,5 disubstituted-4H-1,2,4-triazole as a potential antitubercular and antifungal agent

A number of 5-methyl-2-[(5-substituted aryl-4H-1,2,4-triazol-3-yl)methyl]-2,4-dihydro-3H-pyrazol-3-one (4a-g) and 5-phenyl-1-[(5-substituted aryl-4H-1,2,4-triazol-3-yl)methyl]-1H-tetrazole (8a-g) derivatives were evaluated for in vitro antitubercular and antifungal activity. Compounds 4a-g and 8a-g were evaluated against Mycobacterium tuberculosis H37Rv (ATCC27294) in BACTEC 12B medium using a broth micro dilution assay. The minimum inhibitory concentration (MIC) was determined for compounds that demonstrated ≥ 90% growth inhibition in the primary screening. Results of the biological assay showed that 4-chloro, 3-nitro, 4-methoxy and 2-chloro substituted compounds were found to be antimycobacterial agents at MIC value of 6.25 μg/ml. MIC values for in vitro antifungal activity were determined by liquid broth method. From the newly synthesized series compounds substituted with 4-chloro, 2-chloro and 4-methoxy group exhibited significant antifungal activity against Candida albicans NCIM 3471 and Aspergillus niger NCIM 1196.