Heterocyclic compounds with diverse biological activities: A review of quinazoline and quinazolinone derivatives

Quinazoline and its derivative quinazolinone represent a vital class of nitrogen-containing heterocyclic compounds known for their diverse and potent biological activities. These scaffolds feature a fused benzene - pyrimidine ring system and occur in several isomeric forms, with quinazoline and quinazolinone being the most pharmacologically significant. Various classical and modern synthetic methods have been employed to develop quinazoline/quinazolinone-based frameworks. Quinazoline derivatives have demonstrated a wide array of therapeutic properties, including anticancer, antibacterial, antifungal, antidiabetic, anti-inflammatory, anticonvulsant, antiviral, antimalarial, and antitubercular effects. Many of these compounds have progressed to clinical use due to their high efficacy and favorable drug-like profiles. This review summarizes the biological activities of quinazoline and its derivatives, while also highlighting recent advancements in their synthesis and medicinal applications reported from 2016 to 2025, with particular emphasis on their therapeutic potential and emerging trends in drug discovery.