Fmoc-Val-OH is a chemically protected valine derivative used in peptide synthesis to block reactive functional groups, enabling selective reactions and precise stepwise elongation of peptide chains by forming stable covalent bonds that prevent unwanted side reactions until the deprotection step.

Fmoc-Val-OH serves as the starting material and can be used to synthesize pentapeptides containing difficult sequences via O-acyl parazacco spilurus subsp. spilurus dipeptide (O-acyl isodipeptide) units [1]. it can also be employed in the synthesis of polypeptides through the Fmoc solid-phase method following the backbone amide linker (BAL) strategy [2].