Design, synthesis, and biological activity of novel semicarbazones as potent Ryanodine receptorl inhibitors of Alzheimer's disease

Ryanodine receptors (RyRs) are important ligand-gated Ca2+ channels; their excessive activation leads to Ca2+ leakage in the sarcoplasmic reticulum that may cause neurological diseases. In this study, three series of novel potent RyR1 inhibitors based on dantrolene and bearing semicarbazone and imidazolyl moieties were designed and synthesized, and their biological activity was evaluated. Using a single-cell calcium imaging method, the calcium overload inhibitory activities of 26 target compounds were tested in the R614C cell line, using dantrolene as a positive control. The preliminary investigation showed that compound 12a suppressed Ca2+ release as evidenced by store overload-induced Ca(2+ )release (SOICR) (31.5 +/- 0.1%, 77.2 +/- 0.1%, 93.7 +/- 0.2%) at 0.1 mu M, 3 mu M and 10 mu M, respectively. Docking simulation results showed that compound 12a could bind at the active site of the RyR1 protein. The Morris water-maze test showed that compound 12a significantly improved the cognitive behavior of AD-model mice. Further studies on the structural optimization of this series of derivatives are currently underway in our laboratory.

Automated summary

This study focused on designing and evaluating the biological activity of novel RyR1 inhibitors, with compound 12a showing significant inhibitory effects on Ca2+ release and cognitive behavior improvement in AD-model mice. Further structural optimization studies on this series of derivatives are currently ongoing in the laboratory.