SP4206

SP4206 is an experimental small molecule peptidomimetic that acts as an inhibitor of the Interleukin-2 (IL-2) signaling pathway. Developed by Sunesis Pharmaceuticals, it was designed to disrupt the protein-protein interaction between IL-2 and the alpha subunit of its receptor (IL-2Rα, also known as CD25). SP4206 binds to a specific hydrophobic patch on the surface of IL-2, which is the same site utilized by IL-2Rα, thereby competitively inhibiting the formation of the high-affinity heterotrimeric IL-2 receptor complex. This compound served as a landmark proof-of-concept in drug discovery, demonstrating that small molecules could effectively target and inhibit large, flat protein-protein interfaces that were previously considered 'undruggable.' Although it has been extensively used as a structural biology probe and a reference compound in immunology research, it has not advanced into clinical trials for therapeutic applications.

Other names

2-[2-(2-Cyclohexyl-2-guanidino-acetylamino)-acetylamino]-N-(3-mercapto-propyl)-propionamideDB04278DB-04278DB 04278N-(3-mercaptopropyl)-2-(2-(2-guanidino-2-cyclohexylacetamido)acetamido)propanamide