Fig. 4
From: The timeline of epigenetic drug discovery: from reality to dreams
Second-generation HDAC inhibitors. a Examples of hydroxamic acid, including belinostat (compound 16), dacinostat (compound 17), panobinostat (compound 18), CUDC-101 (compound 19), quisinostat (compound 20), and tefinostat (compound 21). b Benzamide HDAC inhibitors that have reached clinical development, including tacedinaline (compound 22), entinostat (compound 23), mocetinostat (compound 24), and chidamide (compound 25). c Carboxylic acid HDAC inhibitors, including butyric acid (compound 26), pivanex (compound 27), phenylbutyric acid (compound 28), and valproic acid (compound 29)