Design, synthesis, in silico and in vitro evaluation of novel diphenyl ether derivatives as potential antitubercular agents

  • Ashutosh Prasad Tiwari
  • B. Sridhar
  • Helena I. Boshoff
  • Kriti Arora
  • G. Gautham Shenoy
  • K. E. Vandana
  • G. Varadaraj BhatEmail author
Original Article


Diphenyl ether derivatives inhibit mycobacterial cell wall synthesis by inhibiting an enzyme, enoyl-acyl carrier protein reductase (InhA), which catalyses the last step in the fatty acid synthesis cycle of genus Mycobacterium. To select and validate a protein crystal structure of enoyl-acyl carrier protein reductase of Mycobacterium tuberculosis for designing inhibitors using molecular modelling, a cross-docking and correlation study was performed. A series of novel 1-(3-(3-hydroxy-4-phenoxyphenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl) ethan-1-ones were synthesized from this model and screened for their antitubercular activity against M. tuberculosis H37Rv. Compound PYN-8 showed good antitubercular activity on M. tuberculosis H37Rv (MIC = 4–7 µM) and Mycobacterium bovis (% inhibition at 10 µM = 95.91%). Cytotoxicity of all the synthesized derivatives was assessed using various cell lines, and they were found to be safe. Structure of PYN-8 was also confirmed by single-crystal X-ray diffraction. The molecular modelling studies also corroborated the biological activity of the compounds. Further, in silico findings revealed that all these tested compounds exhibited good ADME properties and drug likeness and thus may be considered as potential candidates for further drug development.

Graphic abstract


TB Diphenylether InhA Molecular docking Correlation study Antitubercular 



The authors are thankful to Manipal Academy of Higher Education and Manipal College of Pharmaceutical Sciences for providing necessary supports and facilities to carry out the present research work. Authors are thankful to D’IICT and National Mol Bank (NMB) facility of CSIR-IICT, Hyderabad, India, for the help in biological evaluation of compounds. Authors also thank Manipal-Schrödinger Centre for molecular simulations. This work was funded in part by the Intramural Research Program of the NIH, NIAID.

Compliance with ethical standards

Conflict of interest

The authors confirm that this article content has no conflict of interest.

Supplementary material

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Supplementary material 1 (DOCX 1015 kb)
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Supplementary material 2 (DOCX 1871 kb)


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Manipal College of Pharmaceutical SciencesManipal Academy of Higher EducationManipalIndia
  2. 2.X-ray Crystallography DivisionCSIR – Indian Institute of Chemical TechnologyHyderabadIndia
  3. 3.Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaUSA
  4. 4.Department of Microbiology, Kasturba Medical CollegeManipal Academy of Higher EducationManipalIndia

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