ZYJ-34c is an orally active and potent histone deacetylase inhibitor (HDACi) with IC 50 s of 0.056 μM and 0.146 μM for HDAC6 and HDAC8 , respectively. ZYJ-34c causes G1 phase arrest in low concentration. ZYJ-34c has antiproliferative activities. ZYJ-34c exhibits antitumor potency in MDA-MB-231 and HCT116 xenograft models and possesses antimetastatic potential in a mouse hepatoma-22 (H22) pulmonary metastasis model.