Fig. 2.

Chemical structures of different classes of DNMT and HDAC inhibitors. Antimetabolites 5-azacytidine and decitabine (5-aza-2′-deoxycytidine) are cytidine analogues; these nucleoside derivatives are incorporated into DNA leading to covalent adduct formation, thus acting as mechanistic inhibitors. The non-nucleoside DNMT inhibitor hydralazine interacts within the binding pocket of the enzyme interfering with the DNA methylation mechanism