Synthesis and activity of some new histone deacetylases inhibitors

To explore novel histone deacetylase (HDAC) inhibitors with anti-tumor activity, twelve target compounds were synthesized, and their structures were confirmed by ¹H NMR, MS and elemental analyses.  Evaluation results in vitro showed that compound Ia exhibited potent inhibition against HDAC and is worth for further investigation.  And compounds IIa, IIb, IIIa−IIIi possessed moderate HDAC inhibitory activity.