(S)-3-((tert-Butoxycarbonyl)amino)-4-(4-cyanophenyl)butanoic acid is primarily used in the synthesis of pharmaceuticals, particularly in the development of enzyme inhibitors and receptor modulators. Its structure, featuring a Boc-protected amino group and a cyano-substituted phenyl ring, makes it a valuable intermediate in medicinal chemistry. It is often employed in the preparation of compounds targeting neurological disorders, cardiovascular diseases, and metabolic conditions. Additionally, its chiral center allows for the creation of enantiomerically pure drugs, enhancing specificity and reducing side effects. The compound is also utilized in peptide synthesis and as a building block for complex organic molecules in drug discovery research.