(+)-cis-(2R,3S)-3-Hydroxyproline is a non-proteinogenic amino acid derivative, specifically a hydroxylated derivative of proline. It features a pyrrolidine ring with hydroxyl and carboxylic acid functional groups, and its stereochemistry is defined as (2R,3S). This compound is a key chiral building block in organic synthesis and pharmaceutical research. Its primary significance lies in its role as a crucial component in the synthesis of complex bioactive molecules. It serves as a key intermediate in the production of various pharmaceutical agents, particularly protease inhibitors. A prominent application is its use in the synthesis of Boceprevir, a direct-acting antiviral medication used to treat hepatitis C virus (HCV) infection. The specific stereochemistry of (2R,3S)-3-hydroxyproline is essential for the biological activity of such final drug compounds. As a chiral synthon, it is valued for introducing structural complexity and specific three-dimensional configurations into target molecules. It is typically supplied as a high-purity solid for research and development purposes in medicinal chemistry.