Used as a chiral building block in the synthesis of biologically active compounds, particularly in pharmaceutical development. Its structure allows for selective introduction of the (R)-pyrrolidine moiety, which is valuable in creating enantiomerically pure drugs. Commonly employed in the preparation of protease inhibitors and other therapeutic agents where stereochemistry plays a critical role in activity. The methylsulfonyl group acts as a good leaving group, facilitating nucleophilic substitution reactions under mild conditions. Also utilized in asymmetric synthesis and medicinal chemistry research for constructing complex nitrogen-containing heterocycles.