Design, synthesis, and biological evaluation of novel iNOS inhibitors as potent neuroprotective agents for ischemic stroke

Ischemic stroke (IS) is characterized by intricate pathophysiological mechanisms, where single-target treatments have often proven insufficient. Thus, multi-target therapeutic approaches are essential for effective IS management. In this study, we employed a molecular hybridization strategy, merging the structures of the iNOS inhibitor 1400W and the multi-target neuroprotective agent NBP, to develop a series of novel iNOS inhibitors BN-1 ∼ BN-4 with neuroprotective properties. Among these, BN-4 exhibited the most potent cell protective activity in OGD/R-induced SH-SY5Y and BV-2 cells. BN-4 not only reduced ROS levels induced by OGD/R in SH-SY5Y cells but also mitigated necrosis and apoptosis. By binding to iNOS in a manner similar to 1400W, BN-4 significantly inhibited iNOS activity. Furthermore, BN-4 demonstrated high stability, excellent blood-brain barrier permeability, and more than 100-fold increase in aqueous solubility compared to NBP. Additionally, BN-4 notably decreased infarct size and showed neuroprotective effects in tMCAO rats. These findings indicate that BN-4 holds promise as a novel candidate for treatment IS, offering enhanced therapeutic efficacy due to its superior pharmacokinetic and pharmacodynamic properties.