CTPB is an amide derivative that selectively activates the histone acetyltransferase (HAT) p300, with maximal activation at 275 μM. It directly binds p300. CTPB does not alter PCAF HAT or histone deacetylase activity. It dose-dependently increases the acetylation of histones H3 and H4, with maximal effect at 200 μM.
