Active Motif's CPTH2 is a selective inhibitor of the histone acetyltransferase Gcn5P both in vitro and in vivo (IC50 = 0.8 M) (ref1). In vitro the HAT inhibitory activity of CPTH2 was caused via bridge-interaction with histone H3. In vivo it decreased acetylation of bulk histone H3 at the H3K14ac site.
