DDD00033325 is a cell-permeable small molecule that promotes single human embryonic stem cell survival up to 20-fold over background (EC50 = 3.9 M), with equal or higher potency than the ROCK inhibitor Y-27632 in 5 cell lines (SA461, SA181, SA167, SA121 and SA002) tested at 10 M. An in vitro high-content screening assay, which profiles a panel of more than 70 protein kinases, indicates that this small molecule is more selective than Y-27632 and only displays an inhibitory effect toward ROCK2 (>83% inhibition, ROCK1 was not included in the panel) and PRK2 (76% inhibition) at 10 µM.