Recent Approaches for the Synthesis, Reactions, and Biological Activities of Isoquinolino[2, 3-a]quinazoline Derivatives

Isoquinolinoquinazolines and their derivatives represent a significant class of nitrogenbased heterocycles that have attracted substantial interest from researchers worldwide. This review builds on our previous work by summarizing recent advancements in this class of compounds, specifically focusing on novel isoquinolino[2,3-a] quinazolines published between 1991 and 2026. It highlights their pharmacological and biological activities, as well as the mechanisms of action underlying these effects. Advances in synthetic modification strategies have significantly enhanced the synthesis of isoquinolino[2,3-a] quinazolines, enabling their successful production. Over 128 molecules demonstrating a wide range of biological activities, including antitumor, antimicrobial, analgesic, antioxidant, and cardioprotective effects, have been synthesized and discussed. The total synthesis of Isoquinolino[2,3-a] quinazolines was discussed across 7 classes, each involving distinct compounds, reagents, and methods. This review provides new insights and opportunities for drug discovery involving Isoquinolino[2,3-a] quinazolines.