Integrated stress response (ISR) inhibitor; reverses the effects of eIF2α phosphorylation (IC50 = 5 nM) and restores cell translation capacity. Acts downstream of PERK, targeting interactions between eIF2α kinases and elF2B. Blocks ATF4 production without altering the IRE1 or ATF6 responses in vitro. Displays memory enhancement in hippocampus-dependent spatial and fear-associated learning in rodents. Brain penetrant. Purity 99%. MW (observed): 451.34