Synthesis of pyrrolo(pyrido)[1,2-a]quinazolinones and their benzoannulated analogues: An overview

Angular pyrrolo(pyrido)[1,2-a]quinazolinones, being structurally isomeric to linear pyrrolo(pyrido)[2,1-b]quinazolinone alkaloids, are attractive molecular systems for both synthetic transformations and targeted biomedical research. The pyrrolo(pyrido)[1,2-a]quinazolinone scaffold has proven to be quite effective in the search for compounds with a wide range of pharmacological activities, e.g. anti-inflammatory, antioxidant, antibacterial, antiarrhythmic, and inhibitors of important biotargets. The present review summarises the methods for the synthesis of pyrrolo(pyrido)[1,2-a]quinazolinones as a comprehensive research object, especially in the past decade. They are systematised according to the type of heteroannulation and include the processes of cascade annulation of the pyrimidine and pyrrole (pyridine) cycles to anthranilamides (hydrazides); formation of a pyrimidine nucleus based on ortho-pyrrolyl(pyridinyl) substituted aromatic compounds; annulation of the pyrrole (pyridine) nucleus to a quinazolinone scaffold. It is expected that the generalised material presented will serve as a reliable guide for the rational design of new pharmacologically oriented compounds