ACY-1215 is a potent, cell-permeable and selective inhibitor of histone deacetylase 6 (HDAC6) (IC₅₀ = 5 nM). ACY-1215 is 12-, 10-, 11 and 21-fold less active against HDAC1, HDAC2, HDAC3 and HDAC8, respectively. It displays minimal activities (IC₅₀ > 1 µM) against HDAC4, HDAC5, HDAC7, HDAC9, HDAC11, Sirtuin1, and Sirtuin2. In combination with Tubastatin (Cat. No. 1724), it improves cognition in Alzheimer’s Disease (AD) transgenic mice.