This compound, trans-4-(tert-Butyldiphenylsilyloxy)-L-proline, is a protected derivative of trans-4-hydroxy-L-proline, featuring a tert-butyldiphenylsilyl (TBDPS) group that specifically protects the 4-hydroxyl functionality while leaving the carboxyl group free. It is primarily utilized in organic synthesis, particularly in peptide chemistry, to shield the hydroxyl group during complex synthetic reactions, enabling selective transformations at other sites in the molecule. The free carboxyl allows for straightforward incorporation into peptide sequences. Additionally, it is employed in the synthesis of modified peptides and peptidomimetics, where the steric bulk of the TBDPS group aids in controlling stereochemistry and minimizing unwanted side reactions. Its robustness under diverse reaction conditions positions it as a key reagent in developing pharmaceuticals and bioactive compounds.