Synthesis of new 4-(2,5-dimethylpyrrol-1-yl)/4-pyrrol-1-yl benzoic acid hydrazide analogs and some derived oxadiazole, triazole and pyrrole ring systems: a novel class of potential antibacterial, antifungal and antitubercular agents

A series of 4-(2,5-dimethylpyrrol-1-yl)/4-pyrrol-1-yl benzoic acid hydrazide analogs, some derived 1,3,4-oxadiazoles, 5-substituted-4-amino-1,2,4-triazolin-3-thione and 2,5-dimethyl pyrroles have been synthesized in good yields and structures of these compounds were established by IR, H-1 NMR, C-13 NMR, Mass spectral and elemental analysis. These compounds were evaluated for their preliminary in vitro antibacterial, antifungal and antitubercular activities against Mycobacterium tuberculosis H(37)Rv strain by broth dilution assay method. Twelve of these compounds displayed good antimicrobial activity, with a minimum inhibitory concentration (MIC) values 1-4 mu g mL(-1). Several compounds 4, 8d, 9, 12c-d and 12f-h exhibited good in vitro antitubercular activity with MIC values 1-2 mu g mL(-1). Further, some title compounds were also assessed for their cytotoxic activity (IC50) against mammalian Vero cell lines and A(549) (lung adenocarcinoma) cell lines using MTT assay method. The results reveal that these compounds exhibit antitubercular activity at non-cytotoxic concentrations. Synthesis, spectral studies and antibacterial, antifungal and antitubercular activities of a novel series of pyrrole derivatives are described.