(S)-2-(4-Chlorophenyl)-3-(isopropylamino)propanoic acid hydrochloride is a chiral amino acid derivative. It features a 4-chlorophenyl group, a propanoic acid backbone, and an isopropylamino substituent, all connected to a stereogenic center in the (S)-configuration. The compound is supplied as its hydrochloride salt to enhance stability and solubility. This compound is a key chiral intermediate in the synthesis of Sacubitril, which is the active pharmaceutical ingredient (API) of the prodrug Sacubitril valsartan (also known as LCZ696). Sacubitril valsartan is a first-in-class angiotensin receptor-neprilysin inhibitor (ARNI) used for the treatment of heart failure. The (S)-stereochemistry of this intermediate is crucial for the biological activity of the final drug molecule. As a high-value synthetic building block with a defined pharmaceutical application, its primary use is confined to the production pathway of Sacubitril. It is not a general-purpose synthetic reagent. Handling requires standard precautions for laboratory chemicals.