E3 ligase ligand-linker conjugates 16 are primarily utilized in the field of targeted protein degradation, a cutting-edge approach in drug discovery and therapeutic development. These conjugates are designed to recruit E3 ubiquitin ligases to specific target proteins, marking them for degradation by the proteasome. This mechanism is particularly valuable in eliminating disease-causing proteins that are otherwise challenging to target with traditional small-molecule inhibitors. In cancer research, these conjugates are employed to degrade oncogenic proteins that drive tumor growth and survival. By selectively degrading these proteins, they offer a promising strategy to halt cancer progression. Additionally, they are explored in neurodegenerative diseases to remove misfolded or aggregated proteins implicated in conditions like Alzheimer's or Parkinson's disease. Beyond therapeutics, E3 ligase ligand-linker conjugates 16 are used as tools in chemical biology to study protein function and validate drug targets. Their ability to induce protein degradation provides insights into the roles of specific proteins in cellular processes and disease pathways. This makes them invaluable for both basic research and the development of novel therapeutic interventions.