Assessment of 5-substituted Isatin as Surface Recognition Group: Design, Synthesis, and Antiproliferative Evaluation of Hydroxamates as Novel Histone Deacetylase Inhibitors

Abstract

Histone deacetylase (HDAC) is a promising target for cancer treatment. HDAC inhibitors consist of three pharmacophoric features: an aromatic cap group, zinc binding group (ZBG), and a linker chain connecting cap group to ZBG. Herein, we report on (i) substituted isatin moiety as the cap group that recognizes the surface of active enzyme pocket and (ii) thiosemicarbazide moiety incorporated as linker group responsible for connecting the cap group to ZBG (hydroxamic acid). The synthesized compounds were evaluated for their antiproliferative activity and HDAC enzyme inhibition. The binding mode analysis of proposed compounds was evaluated by docking studies. Several analogs were found to inhibit HDAC and cellular proliferation of Hela cervical cancer cells, with GI₅₀ values in the micromolar range. One compound (Vd) was found to have greater in vitro antiproliferative activity in comparison to other compounds.