Class I HDAC inhibitor (IC50 values are 0.18, 0.74, 44.9 and >100 μM for HDAC1, 3, 8 and 6, respectively). Exhibits antiproliferative effects and induces apoptosis in a range of tumor cell lines in vitro and in vivo. Increases estrogen receptor α- and aromatase expression in breast cancer cells. Inhibits PCB-induced neuronal cell death by preventing HDAC3 binding and histone deacetylation within the synapsin-1 promoter. Purity 99%. MW (observed): 376.41