Abstract
Tricyclic fused-quinoline ring system belongs to a fascinating and versatile class of heterocycles that demonstrates a wide spectrum of biological activities such as anti-malarial, anti-microbial, anti-viral, anti-cancer, analgesic, anthelmintic, cardiovascular, anti-hypoglycaemic, etc. Tricyclic fused-quinolines like pyrroloquinolines, pyranoquinolines, pyrimidoquinolines, furoquinolines, imidazoquinolines, pyrazoloquinolines, thienoquinolines, etc. can be synthesized via a number of efficacious synthetic routes that include mostly multicomponent reactions, transition metal catalysis, Lewis and Bronsted acid catalysis and microwave-assisted reactions. In this review, the focus has been placed on these methods along with various factors affecting yields, stereo- and regioselectivities of products and applications of these protocols to achieve valuable candidates reported during the last five years.
Graphical abstract
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Acknowledgements
The authors acknowledge the support from “Government College University, Faisalabad” and “Higher Education Commission of Pakistan.”