Cyclic Pifithrin-Alpha (HBr), 10 mg

STEMCELL Technologies supplies this small molecule as a hydrobromide salt. It is a cell-permeable and reversible inhibitor of p53-mediated apoptosis and p53-dependent gene transcription. The compound is described as a more stable and less cytotoxic analog of the non-cyclic form of pifithrin-alpha, which is rapidly cyclized under normal cell culture conditions. It has also been reported to activate the aryl hydrocarbon receptor.

With a molecular weight of 349.3 g/mol and a purity of ≥ 95%, the product is provided as a crystalline solid. It is soluble in DMSO and absolute ethanol, each at concentrations ≤ 1.5 mM, and has low solubility in aqueous media. Storage at -20°C is recommended, with protection from prolonged exposure to light; the product remains stable as supplied for 12 months from the date of receipt.

Published applications include maintenance and self-renewal, where the compound reduces UV-induced apoptosis of mouse embryonic stem cells and increases the numbers of mouse hematopoietic stem and progenitor cells in vivo and in vitro while decreasing radiation-induced death of these cells. It has also been used in reprogramming workflows, where it increases the efficiency of reprogramming mouse embryonic fibroblasts to induced pluripotent stem cells. The product is intended for research use only.