Selective inhibitor of ubiquitin-specific protease (USP) 7 (IC50 = 4.2 μM). Displays little-to-no inhibition of other USP variants or proteases such as caspase, cathepsins and serine proteases; exhibits some activity at USP47. Induces elevated p53 and apoptosis in cancer cell lines; displays antiangiogenic activity in vivo. Purity 99%. MW (observed): 348.22