Diketopiperazine (DKP) is a cyclic dipeptide formed from two amino acids. It consists of a six-membered ring containing two carbonyl groups and two nitrogen atoms. DKPs are found in various natural sources, including some fungi and bacteria, and can also be synthesized in laboratories. These compounds have garnered interest in medicinal chemistry due to their potential biological activities, such as antimicrobial and anticancer properties. Research is ongoing to explore their applications in drug development and to understand their mechanisms of action in biological systems.