Advances in Synthesis of 2,3-Dihydroquinazolin-4(1H)-ones

2,3-Dihydroquinazolin-4(1H)-one compounds are an important class of nitrogen-containing fused heterocycles, which possess a wide range of pharmacological and biological activities and have important applications in the fields of synthesis and research & development of drugs. Therefore, its synthetic methods have also attracted considerable attention. In this paper, the main advances in the synthesis of 2,3-dihydroquinazolin-4(1H)-ones and their proposed reaction mechanisms from the raw materials such as o-aminobenzamides, isatoic anhydrides, o-nitrobenzamides, o-azidobenzamide, o-bromobenzamide, o-bromobenzonitrile, o-aminobenzoic acids, o-aminobenzonitrile, o-amino-N-(propa-1,2-dienyl)benzamides, and N-alkyl anilines were introduced and reviewed, respectively. Finally, the synthesis of these compounds was summarized and the prospect of their development was prospected.