(S, S) -CPI-1612 is the isomer of CPI-1612 , and can be used as an experimental control. CPI-1612 is a highly potent, orally active EP300/CBP histone acetyltransferase (HAT) inhibitor with an IC50 of 8.1 nM for EP300 HAT. CPI-1612 has an anticancer activity[1].