Synthesis Characterization and Applications of Benzothiazole Derivatives

Abstract

A novel series of 2-aminobenzothiazole with azetidinone, thiazolidinone, tetrazole and amino substituted derivatives were synthesized. All the synthesized compounds were purified by thin layer chromatography and characterized by elemental analysis, IR, 1H and 13C NMR and Mass spectral analysis. All the synthesized compounds were screened for antibacterial activity against Staphylococcus aureus NCCS 2079, Bacillus cereus NCCS 2106-(gram positive) and Escherichia coli NCCS2065, Pseudomonas aeruginosa NCCS2200 (gram negative) by disc diffusion method. Diethylaminoacetyl-2-aminobenzothiazole showed good antibacterial activity against the tested organism at the concentration of 100 pg/ml. Tetrazole series showed good antibacterial activity against the entire tested organism at the concentration of 250 pg/ml. Thiazolidinone series showed moderate antibacterial activity against the tested organism at the concentration of 250 pg/ml. Azetidinone series did not showed antibacterial activity against all tested organism at the concentration of 250 ug/ml and 500 ug/ml solutions. Study results were compared with standards of Amoxycillin and Cefaclor. Preliminary antifungal screening was performed by agar disc diffusion method against Aspergillus niger NCCS 1196 and Candida albicans NCCS 3471. Tetrazole series only showed good antifungal activity against Aspergillus niger and Candida albicans at the concentration of 250 g/ml when comparable to that of standard (Ketoconazole). The minimum inhibitory concentration of the active compounds was determined. All the synthesized thiazolidinone compounds showed MIC activity against Staphylococcus aureus range between 100-225 pg/ml, Bacillus cereus range between 100-200 pg/ml, Escherichia coli range between 160-225 ug/ml and Pseudomonas aeruginosa range between 125-190 ug/ml. Tetrazole series showed MIC between 50-100 g/ml against the tested bacterial strains. Diethyl/Dimethyl amino substituted benzothiazoles showed good local anesthetic activity when compared to that of standard (Lignocaine).