SYNTHESIS AND BIOLOGICAL EVALUATION OF BENZIMIDAZOLE DERIVATIVES AS ANTIMICROBIAL AGENTS
DOI:
https://doi.org/10.22159/ijcpr.2019v11i6.36356Keywords:
Benzimidazole, Thiadiazole, Microwave irradiation, Spectral studies, Antimicrobial activityAbstract
Objective: The present study aims to synthesize and biological evaluation of benzimidazole derivatives as antimicrobial agents.
Methods: 2-Methylbenzimidazole react with ethyl-chloroacetate gives N1-Ethylacetate-2-methyl-benzimidazole (1), which on reaction with thiosemicarbazide gives N1-acetylthiosemicarbazide-2-methyl-benzimidazole (2). The compound (2) on dehydrative annulation by mineral acid gives N1-(2’-amino-5’-methylene)-1’,3’,4’-thiadiazole-2-methyl-benzimidazole(3), which on condensation with various aromatic and hetero aromatic aldehydes gives N1-(2-substituted-Benzylidene-imino-5’-methylene)-1’, 3’, 4’-Thiadiazole]-2-methyl-benzimidazole(4a-4l).
Results: The reaction sequence involves microwave-induced preparation of N1-Ethylacetate-2-methyl-benzimidazole (1) from reaction of 2-methylbenzimidazole with ethyl-chloroacetate. Further reaction with thiosemicarbazide gives N1-acetylthiosemicarbazide-2-methyl-benzimidazole (2). The compound (2) on dehydrative annulation by sulfuric acid gives N1-(2’-amino-5’-methylene)-1’,3’,4’-thiadiazole-2-methyl-benzimidazole(3), which on condensation with various aromatic and hetero aromatic aldehydes gives N1-(2-substituted-Benzylidene-imino-5’-methylene)-1’, 3’, 4’-Thiadiazole]-2-methyl-benzimidazole(4a-4l). Which were characterized by IR and 1H NMR spectral data.
Conclusion: All the synthesized compounds were screened for antimicrobial activity by cup plate method. Most of the derivatives showed good antimicrobial activity against Gram-Positive and Gram-negative bacteria.
Downloads
References
2. B Soni. Synthesis and evaluation of some new benzimidazole derivatives as potential antimicrobial agents. Int J Comprehensive Pharm 2012;3:1-4.
3. BV Kumar. Synthesis and anti-bacterial activity of some novel 2-(6-fluorochroman-2-yl)-1-alkyl/acyl/aroyl-1H-benzimidazoles. J Med Chem 2006;41:599-604.
4. NR Thimmegowda. Synthesis and biological evaluation of novel 1-(4-methoxyphenethyl)-1Hbenzimidazole-5-carboxylic acid derivatives and their precursors as antileukemic agents. Bioorg Med Chem 2009;19:4594-600.
5. CS Sharma. Synthesis and biological evaluation of some novel mannich bases of benimidazole derivatives. Int J Adv Res Pharm Bio Sci 2011;1:9-15.
6. K Tewari. Synthesis and antiviral activities of N-substituteed-2-substituted-benzimidazole derivatives. Indian J Chem 2006;45:489-93.
7. IJ Kerimov. Synthesis, antifungal and antioxidant screening of some novel benzimidazole derivatives. Enzyme Inhib Med Chem 2007;22:696-701.
8. MC Sharma. Synthesis and antihypertensive activity of some new benzimidazole derivatives of 4’-(6-methoxy-2-substituted-benzimidazole-1-ylmethyl)-biphenyl-2-carboxylic acid in the presences of BF3, OEt2. Pelagia Res Library 2010;1:104-15.
9. MS Yar. In vitro anti-tubercular screening of newly synthesized benzimidazole derivatives. World Academy Sci Engineering Technol 2009;55:593-9.
10. RL Sawant. Synthesis and biological evaluation of some novel 2-phenyl benzimidazole-1-acetamide derivatives as potential anthelmintic agents. Acta Pharma 2011;61:353-61.
11. SS Mahajan. Studies in the synthesis of 2-mercapto-5-methoxybenzimidazole. Indian J Chem 2006;45:1756-8.
12. RS Gaud, GD Gupta. Practical microbiology. 5th edition. Nirali Prakashan; 2006. p. 111-4.