4-Acyl Pyrrole Capped HDAC Inhibitors: A New Scaffold for Hybrid Inhibitors of BET Proteins and Histone Deacetylases as Antileukemia Drug Leads

Multitarget drugs are an emerging alternative to combination therapies. In three iterative cycles of design, synthesis, and biological evaluation, we developed a novel type of potent hybrid inhibitors of bromodomain, and extra-terminal (BET) proteins and histone deacetylases (HDACs) based on the BET inhibitor XD14 and well-established HDAC inhibitors. The most promising new hybrids, 49 and 61, displayed submicromolar inhibitory activity against HDAC1-3 and 6, and BRD4(1), and possess potent antileukemia activity. 49 induced apoptosis more effectively than the combination of ricolinostat and birabresib (1:1). The most balanced dual inhibitor, 61, induced significantly more apoptosis than the related control compounds 62 (no BRD4(1) affinity) and 63 (no HDAC inhibition) as well as the 1:1 combination of both. Additionally, 61 was well tolerated in an in vivo zebrafish toxicity model. Overall, our data suggest an advantage of dual HDAC/BET inhibitors over the combination of two single targeted compounds.

Related Products

Cat.No. Product Name Information
S8001 Ricolinostat (ACY-1215) Ricolinostat (ACY-1215, Rocilinostat) is a selective HDAC6 inhibitor with IC50 of 5 nM in a cell-free assay. It is >10-fold more selective for HDAC6 than HDAC1/2/3 (class I HDACs) with slight activity against HDAC8, minimal activity against HDAC4/5/7/9/11, Sirtuin1, and Sirtuin2. Ricolinostat (ACY-1215) suppresses cell proliferation and promotes apoptosis. Phase 2.

Related Targets

HDAC Apoptosis related