Synthesis, In Vitro Antimycobacterial Activity of Some 2-((5-Amino-1,3,4-Thiadiazol-2-YL)Methyl)-6-Aryl-Tetrahydropyridazin-3-One Derivatives

A series of 2-((5-amino-1,3,4-thiadiazol-2-yl)methyl)-6-aryl-2,3,4,5-tetrahydro-pyridazin-3-one (4a-e) was synthesized and evaluated for its in vitro antimycobacterial activity. All the synthesized compounds were structurally confirmed by using physicochemical and spectral analysis such as melting point, R_f value, elemental analysis, IR, NMR and mass spectra. In vitro antimycobacterial activity was screened by the microplate Alamar Blue Assay (MABA) method against Mycobacterium tuberculosis H37Rv strain. Derivatives with 4-ethyl phenyl substitution (4b) and chloro phenyl substitution (4e) at the p-position of pyridazinone nuclei showed good antimycobacterial activity with a MIC value of 6.25 μg/ml compared to other aryl substitutions such as 4-methoxy phenyl (4a), 4-methyl phenyl (4c) with a MIC value of 25 and 12.5 μg/ml. The results of in vitro antimycobacterial activity revealed that the synthesized compounds have potential antimycobacterial action and can be further optimized and developed as lead compounds.