Synthesis and HDAC1 inhibitory activity of a novel series of coumarin-based amide derivatives for treatment of cancer

Background: Histone deacetylases (HDACs) play a vital role in the epigenetic regulation of transcription and expression. HDAC1 overexpression is seen in many cancers. Methodology: The authors synthesized and evaluated 27 novel coumarin-based amide derivatives for HDAC1 inhibitory activity. The compounds were screened at the US National Cancer Institute, and 5k and 5u were selected for five-dose assays. Compound 5k showed GI50 values of 0.294 and 0.264 μM against MOLT-4 and LOX-IMVI, respectively; whereas 5u had GI50 values of 0.189 and 0.263 μM, respectively. Both derivatives showed better activity than entinostat and suberoylanilide hydroxamic acid. Compound 5k exhibited an IC50 value of 1.00 μM on ACHN cells. Conclusion: Coumarin derivatives exhibited promising HDAC1 inhibitory potential and warrant future development as anticancer agents.

Discovery of quinazolinyl-containing benzamides derivatives as novel HDAC1 inhibitors with in vitro and in vivo antitumor activities

A series of quinazolinyl-containing benzamide derivatives were designed, synthesized and evaluated for their in vitro histone deacetylase 1 (HDAC1) inhibitory activities. Compounds 11a surpassed the known class I selective HDAC inhibitor MS-275 in both HDAC1 enzymatic inhibitory activity and cellular anti-proliferative activity against a selected set of cancer cell types (Hut78, K562, Hep3B and HCT116 cells) with no observed effects on human normal cells. In particular, compound 11a inhibited HDAC1 over the other tested HDACs isoforms (HDAC2, HDAC6 and HDAC8) with acceptable safety profiles. Moreover, compound 11a displayed favorable oral pharmacokinetic properties and showed significant antitumor activity in the A549 tumor xenograft model in vivo.

Design, synthesis and biological evaluation of novel coumarin-based benzamides as potent histone deacetylase inhibitors and anticancer agents

Histone deacetylases (HDACs) are attractive therapeutic targets for the treatment of cancer and other diseases. It has four classes (I-IV), among them especially class I isozyme are involved in promoting tumor cells proliferation, angiogenesis, differentiation, invasion and metastasis and also viable targets for cancer therapeutics. A novel series of coumarin-based benzamides was designed and synthesized as HDAC inhibitors. The cytotoxic activity of the synthesized compounds (8a-u) was evaluated against six human cancer cell lines including HCT116, A2780, MCF7, PC3, HL60 and A549 and a single normal cell line (Huvec). We evaluated their inhibitory activities against pan HDAC and HDAC1 isoform. Four compounds (8f, 8q, 8r and 8u) showed significant cytotoxicity with IC₅₀ in the range of 0.53-57.59 μM on cancer cells and potent pan-HDAC inhibitory activity (consists of HDAC isoenzymes) (IC₅₀ = 0.80-14.81 μM) and HDAC1 inhibitory activity (IC₅₀ = 0.47-0.87 μM and also, had no effect on Huvec (human normal cell line) viability (IC₅₀ > 100 μM). Among them, 8u displayed a higher potency for HDAC1 inhibition with IC₅₀ value of 0.47 ± 0.02 μM near equal to the reference drug Entinostat (IC₅₀ = 0.41 ± 0.06 μM). Molecular docking studies and Molecular dynamics simulation of compound 8a displayed possible mode of interaction between this compound and HDAC1enzyme.