ADDA 5 hydrochloride is primarily utilized in biochemical research as a potent and selective inhibitor of protein phosphatase 2A (PP2A). Its application is significant in studying cellular signaling pathways, particularly those involving phosphorylation and dephosphorylation processes. Researchers employ it to investigate the role of PP2A in various biological functions, including cell cycle regulation, apoptosis, and tumor suppression. Additionally, it is used in pharmacological studies to explore potential therapeutic strategies for diseases where PP2A activity is dysregulated, such as cancer and neurodegenerative disorders. Its inhibitory properties make it a valuable tool for dissecting complex cellular mechanisms and developing targeted treatments.