Purity ~98%. Antibiotic K252A is a staurosporine analogue isolated from a Nocardiopsis strain as a potent inhibitor of protein kinase C. Antibiotic K252A exhibits potent antitumor activity but shows no antimicrobial activity in vitro, or in vivo toxicity in rodents. More extensive investigation has demonstrated that while antibiotic K252A is a potent inhibitor of Ca2+/calmodulin kinase II, it is also active against other kinases, notably myosin light chain kinase, cAMP-dependent protein kinase (PKA), protein kinase C (PKC) and cGMP-dependent protein kinase (PKG). Source: Nocardiopsis sp. Apperance: White solid Solubility: Soluble in ethanol, methanol, DMF or DMSO. Limited water solubility.