StemRegenin 1, 1 mg

An aryl hydrocarbon receptor (AhR) antagonist from STEMCELL Technologies, StemRegenin 1 (SR1) is a small molecule supplied as a crystalline solid with a molecular formula of C₂₄H₂₃N₅OS, a molecular weight of 429.5 g/mol, and a purity of ≥ 98%. Its chemical name is 4-[2-[[2-benzo[b]thien-3-yl-9-(1-methylethyl)-9H-purin-6-yl]amino]ethyl]-phenol (CAS Number 1227633-49-9).

In published research, SR1 promotes the ex vivo expansion of CD34+ human hematopoietic stem cells and the generation of CD34+ hematopoietic progenitor cells from non-human primate induced pluripotent stem cells. It has also been reported to collaborate with UM729 in preventing the differentiation of acute myeloid leukemia (AML) cells in culture, and to stimulate the proliferation and differentiation of CD34+ hematopoietic progenitor cells into dendritic cells. The compound has low solubility in aqueous media, and aqueous working concentrations up to 1 µM can be achieved by dilution from a DMSO stock solution. For use as a cell culture supplement, the stock should be diluted into culture medium immediately before use, and the final DMSO concentration kept below 0.1% to avoid potential cell toxicity. Stock solutions in DMSO can be prepared at concentrations up to 25 mM; the product is stable at -20°C as supplied and should be protected from prolonged exposure to light.

According to the manufacturer's safety data sheet, the compound is classified as harmful if swallowed and causes skin and serious eye irritation, as well as possible respiratory irritation, so protective gloves, eye and face protection, and adequate ventilation are recommended during handling.