Antimicrobial efficacy of n-[3- chloro-(substituted aryl)-4-oxoazetidin- 1-yl] pyridine-4- carboxamides against resistant bacterial strains obtained from clinical isolates


  • Asha B. Thomas Dr d Y patil Inst pharm Sci research, Pune , MH, India
  • Rabindra K. Nanda Dr d Y patil Inst pharm Sci research, Pune , MH, India
  • Lata P. Kothapalli Dr d Y patil Inst pharm Sci research, Pune , MH, India


2-Azetidinone, Antimicrobial, β-lactamase inhibitory, Multi-drug resistant strains



Background: The treatment of infectious diseases is still an important and challenging problem due to emerging infectious diseases and increasing number of multi-drug resistant microbial pathogens which cause a variety of illnesses ranging from hospital-acquired pneumonia, bloodstream infections, urinary tract infections from catheters, abdominal infections and even meningitis.

Methods: The main objective of the present study was to evaluate the antimicrobial efficacy and β-lactamase inhibitory activity of the synthesized 2-azetidinones against resistant bacterial strains obtained from clinical isolates.


Results: The tested 2-azetidinones exhibited antimicrobial efficacy comparable to the standard drugs Ampicillin and Griseofelvin. Among the tested compounds, N-[3-chloro-2-(2,5-dimethoxyphenyl)-4-oxoazetidin-1-yl]pyridine-4-carboxamide(5o) exhibited the highest activity with MIC of 6.25 µg/mL (Gram +ve and Gram –ve bacteria),1.56 µg/mL (A. niger) and 3.12 µg/mL(A. terrus and P. chrysogenum) respectively. Also all the screened compounds (5d, 5f, 5h,5j,5o) exhibited more pronounced activity (MIC: 125 µg/mL) against resistant K. pneumonia obtained from clinical isolates compared to standard antibiotic Amoxycillin. The compounds when tested as admixtures with the standard antibiotic amoxicillin (1:2) exhibited similar antibacterial spectra in comparison to the most widely employed clinical combination Augmentin. The 2-azetidinones

can prove to be a cheaper alternative with similar potential β-lactamase inhibitory activity thereby proving their utility and benefit towards the development of anti-infectives for the treatment of infections caused by drug resistant microorganisms.

Author Biographies

Asha B. Thomas, Dr d Y patil Inst pharm Sci research, Pune , MH, India

Associate Professor, Dept of Pharm chem

Rabindra K. Nanda, Dr d Y patil Inst pharm Sci research, Pune , MH, India

Professor,Dept of Pharm Chem

Lata P. Kothapalli, Dr d Y patil Inst pharm Sci research, Pune , MH, India

Associate Professor, Dept of Pharm chem



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