Identification of a New Isoindole-2-yl Scaffold as a Qo and Qi Dual Inhibitor of Cytochrome bc 1 Complex: Virtual Screening, Synthesis, and Biochemical Assay

  • Homa Azizian
  • Kowsar Bagherzadeh
  • Sophia Shahbazi
  • Niusha Sharifi
  • Massoud AmanlouEmail author
Original Research Article


Respiratory chain ubiquinol–cytochrome (cyt) c oxidoreductase (cyt bc 1 or complex III) has been demonstrated as a promising target for numerous antibiotics and fungicide applications. In this study, a virtual screening of NCI diversity database was carried out in order to find novel Qo/Qi cyt bc 1 complex inhibitors. Structure-based virtual screening and molecular docking methodology were employed to further screen compounds with inhibition activity against cyt bc 1 complex after extensive reliability validation protocol with cross-docking method and identification of the best score functions. Subsequently, the application of rational filtering procedure over the target database resulted in the elucidation of a novel class of cyt bc 1 complex potent inhibitors with comparable binding energies and biological activities to those of the standard inhibitor, antimycin.


Cytochrome bc1 complex Virtual screening LibDock Scoring function Qo oxidative site Qi reductive site 



The authors are grateful to the Research Council of Tehran University of Medical Sciences for financial support to this research work.


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Copyright information

© Springer-Verlag 2017

Authors and Affiliations

  1. 1.Department of Medicinal Chemistry, School of Pharmacy, International CampusIran University of Medical SciencesTehranIran
  2. 2.Razi Drug Research CenterIran University of Medical SciencesTehranIran
  3. 3.Department of Medicinal Chemistry, Faculty of Pharmacy and Drug Design and Development Research CenterTehran University of Medical SciencesTehranIran

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