Wangresin is widely used in solid-phase peptide synthesis (SPPS) as a polystyrene-based resin with acid-labile linker functionality. It enables the stepwise assembly of peptides by providing a stable support for amino acid coupling, while allowing mild cleavage of the final peptide product using trifluoroacetic acid (TFA). Its high loading capacity and excellent swelling properties in common organic solvents make it suitable for both manual and automated synthesis. Wangresin is particularly effective for synthesizing peptides with C-terminal carboxylic acid groups, as it forms ester linkages that are selectively cleaved without affecting side-chain protecting groups when orthogonal protection strategies are employed. It is a preferred choice in research and pharmaceutical development for producing pure and sequence-defined peptides.