Used as a chiral building block in the synthesis of pharmaceuticals, particularly in the development of bioactive peptides and peptidomimetics. Its rigid diketopiperazine structure provides conformational stability, making it valuable in drug design for enhancing metabolic stability and receptor selectivity. Commonly employed in asymmetric synthesis to introduce stereochemical control. Also utilized in the preparation of enzyme inhibitors and as a scaffold in combinatorial chemistry for generating diverse compound libraries.