NQDI-1 is a specific inhibitor of apoptosis signal-regulating kinase 1 (ASK1) (IC50 = 3 μM; Ki = 500 nM) that demonstrates potent selectivity against various serine/threonine and tyrosine protein kinases. It has been used to promote survival of induced pluripotent stem cell populations and to protect neurons from reactive oxygen species-induced apoptosis in a model of ischemia. MW: 319.31. Purity ≥98% by HPLC