Dihydropyrimidinones are organic compounds characterized by a six-membered ring structure containing two nitrogen atoms. They are derivatives of pyrimidine and are often involved in various chemical reactions, making them important in medicinal chemistry and drug development. These compounds can be synthesized through different methods, including the Biginelli reaction, which combines aldehydes, ureas, and β-keto esters. Dihydropyrimidinones have shown potential biological activities, including antimicrobial and anticancer properties, making them a focus of research in pharmacology.