D-Cyclopropylglycine is a non-proteinogenic amino acid characterized by a cyclopropane ring attached to the alpha-carbon of the glycine backbone. This unique structure imparts significant conformational constraints and metabolic stability, making it a valuable chiral building block in medicinal chemistry. Its primary application is as a key intermediate in the synthesis of pharmaceutical compounds. It serves as a crucial precursor for the production of various drugs, including specific antibiotics and enzyme inhibitors. The rigid cyclopropyl moiety is often incorporated to modulate the biological activity, potency, and pharmacokinetic properties of target molecules. Beyond its role as a pharmaceutical intermediate, D-cyclopropylglycine is also employed in biochemical research as a substrate or inhibitor for enzymes such as D-amino acid oxidase (DAAO). Its high purity and defined stereochemistry make it a reliable reagent for constructing complex peptide mimetics and exploring structure-activity relationships in drug discovery programs.