PD98059, 1 mg

A selective, cell-permeable inhibitor of the MEK/ERK pathway, supplied by STEMCELL Technologies, prevents the activation of MEK1 and MEK2 by upstream kinases without inhibiting activated MEK or the p38 MAPK pathway. The compound has a chemical name of 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one (CAS 167869-21-8), a chemical formula of C₁₆H₁₃NO₃, a molecular weight of 267.3 g/mol, and a purity of ≥ 98%. Reported IC₅₀ values are 2–7 µM for MEK1 and 50 µM for MEK2.

The product is supplied as a crystalline solid and remains stable at -20°C for 12 months from the date of receipt when protected from prolonged exposure to light. The compound has low solubility in aqueous media and is soluble in DMSO at concentrations up to 70 mM. For use as a cell culture supplement, the stock solution should be diluted into culture medium immediately before use, and final DMSO or absolute ethanol concentration should be kept below 0.1% to avoid potential cell toxicity. The product is for research use only.

Published applications include enhancement of growth and self-renewal of mouse embryonic stem cells, derivation of mouse ES cells from the refractory CBA mouse strain, blocking of mouse ES cell differentiation, enhancement of adipogenic differentiation and blocking of osteogenic differentiation of human mesenchymal stem cells, and reduction of AML blast colony numbers with minimal effect on normal hematopoietic progenitors.