Synthesis and Anti-TB Activity Studies of Benzothiazole Guanidinyl Derivatives

Compounds containing CN3 group in the open chain or in the ring system are called guanidine and are found in a variety of compounds occurring in natural and synthetic sources. The presence of the guanidine sub unit in the synthesized compound helps to enhance the activity, which helps to interact with the various organisms through the hydrogen bonding. A series of Guanidinyl benzothiazole derivatives were synthesized and evaluated for their anti-mycobacterial activity and cytotoxicity. Antimycobacterial study indicates that all the synthesized compounds were appreciably active and many of the compounds have MIC values lower than the standard drugs. The guanidinyl group and electron donating group present in the molecule interacts with the microorganism and arrest the further growth, so synthesized compounds exhibit the excellent activity and some of the compound has MIC at 1.6 μg/mL. In order to rationalize the biological results of the synthesized compounds, molecular docking studies with enoyl acyl carrier reductase (InhA) of M. tuberculosis were performed and the synthesized compounds shows the remarkable docking score -5.85 to -9.27, which can be compared with the standard drug Isoniazid (INH) with -6.61 as docking score.

Keywords: Acetone, Activity, Alamar Blue Assay, Ammonium thiocyanate, Anti-TB, Benzothiazole, Benzoyl Chloride, Docking, DprE1, Guanidine, in-vitro, in-silico, InhA, IC50 value, Mercuric chloride, MIC, Pyrazinamide, Reflux, Triethyl amine, Tuberculosis , Tyrosine.