This compound, 4-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)-1-methyl-1H-pyrrole-2-carboxylic acid, is a specialized Fmoc-protected building block used in solid-phase peptide synthesis (SPPS). The Fmoc group protects the amino group at the 4-position of the 1-methylpyrrole ring, enabling controlled incorporation of the pyrrole-2-carboxylic acid moiety into peptide chains. It prevents unwanted side reactions during coupling steps and can be selectively removed under mild basic conditions, such as with piperidine. This reagent is essential for synthesizing complex peptides containing non-natural pyrrole units, with applications in medicinal chemistry, drug discovery, and biochemical research.