Used as a key intermediate in the synthesis of pharmaceuticals, particularly in the development of kinase inhibitors and other bioactive molecules. Its phenolic and phosphonic functional groups allow for versatile chemical modifications, making it valuable in medicinal chemistry. It also serves as a building block in the preparation of specialty polymers and ligands for metal coordination, useful in catalysis and material science. Additionally, its structural similarity to tyrosine enables applications in biochemical research and the design of enzyme inhibitors.