N-(2,4-Dinitrophenyl)-L-alanine methyl ester is a DNP-derivatized amino acid ester used primarily as a reference standard in analytical chemistry for the identification and quantification of amino acids, particularly alanine. The 2,4-dinitrophenyl (DNP) group provides strong UV absorbance and yellow color, enabling sensitive detection and separation by UV-Vis spectroscopy, TLC, or HPLC. It serves as a calibration standard in chromatographic analyses of protein hydrolysates, biochemical assays, and environmental samples containing amino compounds. Additionally, it can act as an intermediate in organic synthesis for preparing peptide analogs or bioactive molecules.