Elevenostat (JB3-22), is a small molecule hydroxamic acid derivative that acts as a HDAC11-selective inhibitor. Reporter assays using a luciferase-linked Foxp3 promoter shows that HDAC11 decreases the signal driven by NFκB/p65, alone or in the presence of transfected Foxp3, and impairs luciferase activity driven by p65, Foxp3 and the HAT enzyme, p300. The inhibitory effects of HDAC11 at the Foxp3 promoter are reversed by Elevenostat (JB3-22), (IC50 0.235?μM). Elevenostat also partially reverses the inhibitory effect of HDAC11 on p300-induced Foxp3 acetylation at lysine 31 consistent with the ability of HDAC11 to directly regulate acetylation of Foxp3. MW: 315.33. Purity ≥95%