CS4 is a selective HDAC inhibitor, with IC50 values for HDAC1, HDAC6, HDAC8, HDAC4, and HDAC11 reported as 38 nM, 12 nM, 5.8 μM, 19 μM, and 61 μM, respectively. It enhances the acetylation of α-tubulin and histone 3 (histone 3). Additionally, CS4 activates PPARγ and blocks glycolysis (glycolysis). It induces cell cycle arrest at the G2 phase and triggers apoptosis (apoptosis), exhibiting anticancer effects both in vitro and in vivo.