Synthesis and in-vitro antimycobacterial activity of amino-5-[(substituted) phenyl]-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro-1H-1-pyrazolylmethanethione.

A series of amino-5-[(substituted) phenyl]-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro-1H- 1-pyrazolylmethanethione were synthesized by the reaction between thiosemicarbazide and chalcones and were tested for their antimycobacterial activity in vitro against Mycobacterium tuberculosis H37Rv and INH resistant Mycobacterium tuberculosis using bactec method. Among the synthesized compounds, compound (4b), amino-5-(4-chlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4, 5-dihydro-H-1-pyrazolylmethanethione was found to be the most active agent against Mycobacterium tuberculosis H37Rv (MTB) and INH resistant Mycobacterium tuberculosis (INHR-MTB) with minimum inhibitory concentration of 0.43 microM . When compared to INH-compound (4b) was found to be 1.62 fold and 26.41 fold more active against MTB and INHR-MTB, respectively.