
SYNTHESIS OF NOVEL METHOXY SUBSTITUTED BENZOTHIAZOLE DERIVATIVES AND ANTIBACTERIAL ACTIVITY AGAINST ESCHERICHIA COLI
Author(s) -
A. K. Gupta
Publication year - 2018
Publication title -
asian journal of pharmaceutical and clinical research
Language(s) - English
Resource type - Journals
eISSN - 2455-3891
pISSN - 0974-2441
DOI - 10.22159/ajpcr.2018.v11i9.28095
Subject(s) - benzothiazole , chemistry , antibacterial activity , aniline , escherichia coli , pyridine , nuclear chemistry , organic chemistry , bacteria , biochemistry , biology , genetics , gene
Objectives: Escherichia coli is a Gram-negative rod (bacillus) in the family Enterobacteriaceae. In general, it is harmless, but some special species could cause harmful infection. In the recent era, the number of antibiotics is available to combat infection caused by E. coli but because of resistance developed against available antibiotics research is continuously going on to synthesize newer antibiotic to overcome this problem. Synthesis and screening of benzothiazole derivatives have great importance in heterocyclic chemistry because of its potent and significant biological activities against E. coli especially methoxy substitution at benzothiazole.Methods: Methoxy substituted benzothiazole derivatives were synthesized by reaction of 3- chloro-4-methoxy-aniline with potassium thiocyanate under temperature control and presence of bromine in glacial acetic acid and ammonia. Substituted nitrobenzamides then synthesized by condensation of 2-amino-4-chloro-5-methoxy-benzothiazole with 2 (3 or 4)-nitrobenzoyl chloride acid in the presence of dry pyridine and acetone. Finally, newly synthesized derivatives (K-01 to K-09) were synthesized through replacing of chlorine of nitrobenzamide by reaction with 2-nitroaniline, 3-nitroaniline, and 4-nitroaniline in the presence of dimethoxy formamide. Analytical characterization was performed by thin-layer chromatography, melting point, infrared, and nuclear magnetic resonance. Antibacterial activity was performed against E. coli by cup plate method (diffusion technique) using streptomycin as standard. Compound K-03 showed potent antibacterial activity against E. coli at both concentrations 50 μg/mL and 100 μg/mL as compared to standard.Results: Compound D-03 exhibited excellent activity among all synthesized compounds.Conclusion: In the present work, efforts have been made to synthesized methoxy substituted benzothiazole derivatives and screened for antibacterial activity. Compound K-03 found as most active against E. coli.