CYD19 is a potent Snail/HDAC dual target inhibitor. CYD19 displays potent inhibitory activity against HDAC1 with an IC50 of 0.405 μM and potent inhibition against Snail with a Kd of 0.18 μM. CYD19 increases histone H4 acetylation in HCT-116 cells and decreases the expression of Snail protein to induce cell apoptosis.