PS210 is a potent and selective PDK1 activator (Kd: 3 µM) that binds its PIF pocket without affecting kinases like S6K or Akt. Its prodrug, PS423, acts as a substrate-selective cellular PDK1 inhibitor, blocking S6K phosphorylation. These compounds are valuable research tools for studying PDK1-dependent signaling pathways in cancer and metabolic disease models.