Synthetic Routes to Symmetric Bisbenzimidazoles: A Review

 





  



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

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                                              

                                 

                                            

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                                                                           

   



 



856298

                                                                                                         





 



 

  







 







 



  



 





 



 

 





 

 

 





 

 





  











 







 

 



 





 

   

























 







 













 

                                                                                                       

                                                                                           









 





 





































     



 

 









 

 



 





 



 

 



 

 





 

 







 























 







 

 



 











 

   



















 

 





 



                                                                        

                                                      







 















     









 

 







 









 





  



  



 

 





















 





 

 

















 





  











 

 

 



  

















 

 



  

 



   







 

 









   

                                                             

                                                                                 





 











 

 









  



  

 









 











 





 





 











































































































  







 































 

 



  



  

 

 

  



  









 













 



 















 





                                                    

                                             







 





 

















 

 

 



 



 

 

  

 



  



 

 









 



 

 

  



 

 





 





 









 



 

 







 



  

 

 



 











 







 

 



    







 

 

 







                                                                                  

                                                                                           





 









  







 























  







 















 







  













 





  

   

 

 







  

   





 

 

 



  





  



 





 

 



                              

         

                   

                         

                                      

                    

                        





  

 















   

















 



















 

 



























   







 



 





















 







 

 



 

 

 



 

 

 



 

  

 

  



                                                                 

                                                          











 

 

 





 









 

 







  





 











 

   









 

 









 

 

















  

 







 





     

 

 

 

        

                                                     

                                                              





 















   

 





 





  







 









 













 





 

  

 











 

     

 

 

 

 

 

 



                                                                                                   

                                                                                                                





 



 











  

 

 





  

  

  







  





 









 







 



 

 









  

 

 



 

   

 





  









  













   



 







 





                             

                   





 







 





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





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



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  



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

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





 



 



 

















 





 







 



 





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

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

  









 

  



 

  





  



                              

                        

                   

                   





 





 

 



 















 



 

  









 













 







  

  

 























 









 



 

   





























   

 

























 





  

   











 





 









 

































     



 

 

  

 





  



  

 



  







  









 

  

 



           







  

 

   

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 

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                                                                                                                                           

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 

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                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              

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                                                                                                                                                                                                                                                                                                                                                                                                                              

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                                                                                                                                                                                        

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                                                                                                                                                                                             

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