E3 ligase Ligand 18 is primarily utilized in the field of targeted protein degradation, a cutting-edge approach in drug discovery and therapeutic development. It serves as a key component in the design of PROTACs (Proteolysis Targeting Chimeras), which are bifunctional molecules that facilitate the degradation of specific disease-causing proteins. By binding to E3 ubiquitin ligases, this ligand helps recruit the ubiquitin-proteasome system to tag unwanted proteins for destruction, offering a promising strategy for treating conditions like cancer, neurodegenerative diseases, and other disorders driven by aberrant protein activity. Its application is particularly valuable in cases where traditional inhibitors fail to effectively target proteins of interest.