(2S,5R)-2-Ethyl-5-methyl-N-Boc-piperazine is a chiral piperazine derivative featuring a tert-butoxycarbonyl (Boc) protecting group on one nitrogen atom. This compound is characterized by two stereocenters, conferring specific three-dimensional geometry crucial for its biological activity and synthetic utility. This molecule serves as a key chiral building block in pharmaceutical research and development. Its primary application is as a sophisticated intermediate in the synthesis of complex drug candidates, particularly those targeting the central nervous system (CNS) and other therapeutic areas where the piperazine scaffold is prevalent. The Boc-protected amine functionality allows for selective deprotection and further derivatization, making it a versatile synthon for constructing molecules with precise stereochemistry. As a protected chiral diamine, it is a valuable reagent in medicinal chemistry for introducing the 2,5-disubstituted piperazine moiety into target structures. Its use facilitates the exploration of structure-activity relationships (SAR) in drug discovery programs.