Tert-Butyl ((R)-1-((S)-oxiran-2-yl)-2-phenylethyl)carbamate is a chiral organic compound featuring a protected amine group (as a tert-butyl carbamate, Boc) and an epoxide (oxirane) ring. The molecule contains two stereocenters, designated as (R) and (S), making it a valuable non-racemic building block for asymmetric synthesis. This compound is primarily utilized as a key chiral intermediate in pharmaceutical research and development. Its structure, combining a Boc-protected amine and a reactive epoxide, allows it to serve as a precursor for synthesizing more complex molecules, particularly those containing β-amino alcohol motifs. These motifs are common in various bioactive compounds and active pharmaceutical ingredients (APIs). The epoxide ring is susceptible to nucleophilic ring-opening reactions, enabling the introduction of diverse functional groups in a stereocontrolled manner. The Boc protecting group can be readily removed under acidic conditions to reveal the free amine for further derivatization. Its application is centered on the construction of chiral drug candidates rather than as a bulk commodity or a material for non-pharmaceutical uses.