N-Fmoc-piperidine-2-carboxylic acid, also known as Fmoc-pipecolic acid, is the 9-fluorenylmethoxycarbonyl (Fmoc)-protected derivative of pipecolic acid, a cyclic non-proteinogenic amino acid. It serves as a key building block in solid-phase peptide synthesis (SPPS) for incorporating pipecolic acid residues into peptide sequences. The Fmoc group protects the α-amino group, enabling selective deprotection with bases such as piperidine during the stepwise assembly of complex peptides while maintaining chain integrity. Its compatibility with common coupling reagents and solvents makes it versatile for organic and medicinal chemistry applications, including the synthesis of peptidomimetics, bioactive compounds, and contributions to drug discovery and biochemical research.