Selective non-peptide inhibitor of caspase-3 (Ki = 247 nM); displays > 40-fold selectivity over caspases 1, 2, 6, 7 and 8 (Ki > 10 μM). Completely blocks staurosporine-induced intracellular DEVDase activity in SH-SY5Y cells (IC50 = 14.9 μM).