Histone deacetylase inhibitors(HDIs)are an increasingly important class of cancer-targeting agent.Two kinds of small molecule histone deacetylase inhibitors,mainly employing the motifs of the two known HDAC inhibitors MGCD0103 and SAHA as the basic scaffolds,were designed,synthesized and evaluated for the preliminary biological activity.Strikingly,these two compounds regained a long half-life potency like MGCD0103 and retained the non-selectivity for HDAC1 versus HDAC6 derived from SAHA.Together,these two compounds combining both the advantages of MGCD0103 and SAHA could be considered as novel histone deacetylase inhibitors in targeted drug development and possibly anticipated to be more effective under the clinical trials.