The (R)-4-Isopropyloxazolidine-2,5-dione is the N-carboxyanhydride (NCA) of (R)-valine, a chiral reagent used in ring-opening polymerization (ROP) to synthesize optically active polypeptides and poly(amino acids). It facilitates the formation of peptide bonds with high stereochemical fidelity, preserving the chirality of the alpha-carbon. This compound is essential in the preparation of biomimetic materials, protein mimics, and pharmaceutical intermediates where defined stereochemistry is required. Polymerization typically proceeds under mild conditions using initiators like amines or metal catalysts, yielding polymers with controlled molecular weights and narrow polydispersity.