Synthesis of Linear Azolo and Pyrido Quinolines from Quinoline Derivatives

Abstract

Angular N-tricyclic systems as triazolo(4,5-f)quinolines, triazolo(4,5-h)quinolines, imidazo(4,5-f)quinolines, imidazo(4,5- h)quinolines were in the past obtained by connection of either f or h sides of the quinoline ring and both the adjacent carbon atoms of five-membered rings containing nitrogen atoms. Several attempts at obtaining the corresponding linear N-tricycles were made in the last century, but only the angular derivatives were obtained. Since 2000 a new simple pathway, involving suitable quinoline derivatives, which afforded the linear azolo and pyrido quinolines (imidazo(4,5-g)quinolines, triazolo(4,5-g)quinolines and pyrido(2,3- g)quinoxalines) has been developed. Several linear N-tricyclic derivatives have shown some interesting pharmaceutical activity.