Article Sidebar
Published:
Mar 7, 2017Keywords:
Article Details
Submission of a manuscript to this journal is a representation that the manuscript has not been published previously and is not under consideration for publication elsewhere.
All authors named in each manuscript would be required to sign a form (to be supplied by the Editor) so that they may retain their copyright in the article but to assign to us (the Publishers) and its licensees in perpetuity, in all forms, formats and media (whether known or created in the future) to (i) publish, reproduce, distribute, display and store the contribution, (ii) translate the contribution into other languages, create adaptations, reprints, include within collections and create summaries, extracts and/or abstracts of the contribution, (iii) create any other derivative works(s) based on the contribution, (iv) to exploit all subsidiary rights in the contribution, (v) the inclusion of electronic links from the contribution to third party material where-ever it may be located, and (vi) license any thrid party to do any or all of the above.
Main Article Content
Synthesis of N-substituted acetamide derivatives of azinane-bearing 1,3,4-oxadiazole nucleus and screening for antibacterial activity
Abstract
Purpose: To synthesize some acetamide derivatives bearing azinane and 1,3,4-oxadiazole heterocyclic cores and to evaluate their antibacterial potentials.
Methods: Ethyl piperidin-4-carboxylate (2) was converted to ethyl 1-[(4-chlorophenyl)sulfonyl]piperidin- 4-carboxylate (3), 1-[(4-chlorophenyl)sulfonyl]piperidin-4-carbohydrazide (4) and 5-[1-(4-
chlorophenylsulfonyl)-4-piperidinyl]-1,3,4-oxadiazol-2-thiol (5) using three consecutive steps. The target molecules, 5-{1-[(4-chlorophenyl)sulfonyl]piperidin-4-yl}-2-{[N-(substituted)-2-acetamoyl]thio]}-1,3,4- oxadiazole (8a-n) were synthesized by stirring 5 and N-aryl-2-bromoacetamides (7a-n) in an aprotic polar solvent. The structures were corroborated by infrared (IR), electron impact mass spectrometry (EIMS) and proton/carbon nuclear magnetic resonance (1H/13C-NMR) spectroscopic techniques. The evaluation of antibacterial activity was based on the effect on the increase in absorbance of the broth medium due to log phase microbial growth.
Results: Compound 8g bearing a 2-methylphenyl group was the most the active growth inhibitor of Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis bacterial strains with minimum inhibitory concentrations (MIC) of 10.63±0.97, 10.31±1.00, 10.45 ± 0.94 and 11.77±5.00 μM, respectively. Ciprofloxacin was used as reference standard.
Conclusion: All the synthesized compounds are moderate inhibitors but relatively more active against Gram-negative bacterial strains. 5-{1-[(4- Chlorophenyl)sulfonyl]piperidin-4-yl}-2-{[N-(2-methylphenyl)-2- acetamoyl]thio]}-1,3,4-oxadiazole (8g) is the most active growth inhibitor of all the strains except Staphylococcus aureus.
Keywords: 1,3,4-Oxadiazole, Acetamides, Antibacterial activity, Piperidine
