Fmoc-D-9-anthrylalanine is a non-natural, fluorescent amino acid derivative. Its structure features a D-configuration alanine backbone with a bulky, hydrophobic 9-anthryl group attached to the beta-carbon, and an N-terminal Fmoc (9-fluorenylmethoxycarbonyl) protecting group. This combination makes it a specialized building block in solid-phase peptide synthesis (SPPS). The primary application of this compound is in peptide chemistry and biophysical research. The large, planar anthracene moiety serves as a sensitive intrinsic fluorescent probe. When incorporated into peptides, it allows for studying peptide conformation, dynamics, aggregation (e.g., in amyloid research), and interactions with membranes or proteins through fluorescence spectroscopy, anisotropy, and energy transfer techniques. The D-configuration enhances metabolic stability against proteases in potential therapeutic peptides. As an Fmoc-protected derivative, it is directly compatible with standard Fmoc-SPPS protocols. Its unique structure places it at the intersection of peptide tools and advanced organic synthesis, enabling the creation of peptides with tailored photophysical properties for diagnostic and research applications.