A derivative of Blebbistatin, a compound that blockes myosin II-dependent cell processes. As part of a defined medium for growth of human Pluripotent stem (hPS) cells, Blebbistatin acts as an inhibitor of nonmuscle myosin II (NMII) and enhances the survival of hPS cells. Preventing cell death of Human pluripotent stem (hPS) cells, such as human embryonic stem (hES) and induced pluripotent stem (hiPS) cells, has been a stumbling block to avenues of investigation of with these cell types. The most current culture methods for growing hPS cells require animal-derived materials like Matrigel, for coating the culture surfaces, without which hPS cells cannot adhere to the culture plate. The drawback in using these feeder cells is they can potentially contaminate hPS cells by introducing viruses and other unknown pathogens. The active enantiomer of Blebbistatin (so named because of its ability to block cell blebbing) is the (S)-(-)-Blebbistatin form. United States Biological offers the racemic