Fmoc-Osu

Fmoc-OSu is an activated ester derivative of Fmoc (9-fluorenylmethoxycarbonyl) widely used in peptide synthesis. It serves as an efficient reagent for the introduction of the Fmoc protecting group to amines under mild conditions.
Due to its high reactivity and stability, Fmoc-OSu is commonly employed in solid-phase peptide synthesis (SPPS) and solution-phase peptide synthesis for selective protection of amino groups.