Structure-based optimization of Toddacoumalone as highly potent and selective PDE4 inhibitors with anti-inflammatory effects.
Zhou, F., Huang, Y., Liu, L., Song, Z., Hou, K.Q., Yang, Y., Luo, H.B., Huang, Y.Y., Xiong, X.F.(2022) Biochem Pharmacol 202: 115123-115123
- PubMed: 35688178 
- DOI: https://doi.org/10.1016/j.bcp.2022.115123
- Primary Citation of Related Structures:  
7XBB - PubMed Abstract: 
Phosphodiesterase-4 (PDE4) is an important drug target for inflammatory diseases. Previously, we identified a series of novel PDE4 inhibitors derived from the natural Toddacoumalone, among which the hit compound 2 with a naphthyridine scaffold showed moderate potency with the IC 50 value of 400 nM. Based on the co-crystal structure of PDE4D-2, further structural optimizations and structure-activity relationship studies led to a highly potent PDE4 inhibitor 23a with the IC 50 value of 0.25 nM and excellent selectivity profiles over other PDEs (>4000-fold). The co-crystal structure of PDE4D-23a elucidated that 23a has strong interactions with the M and Q pocket of PDE4D. Importantly, compound 23a significantly inhibits the release of inflammatory cytokines TNF-α and IL-6 in lipopolysaccharide-stimulated RAW264.7 cells. Thus, compound 23a with a naphthyridine scaffold is a promising PDE4 inhibitor for the treatment of inflammatory diseases.
Organizational Affiliation: 
National-Local Joint Engineering Laboratory of Druggability and New Drugs Evaluation, Guangdong Province Engineering Laboratory for Druggability and New Drug Evaluation, School of Pharmaceutical Sciences, Sun Yat-sen University, 510006 Guangzhou, PR China.