SB 218078

A cell-permeable, ATP competitive, and reversible indolocarbazole derivative that acts as a potent inhibitor of checkpoint kinase (Chk1) in vitro (K_i = 15 nM). Binds to the ATP-binding pocket of Chk1, producing only slight changes in the protein conformation. Also inhibits the activity of CDK1 (K_i = 23 nM), CDK2 (K_i = 5.6 nM), and CDK4 (K_i = 16 nM). Inhibits Chk1 phosphorylation of Cdc25C (IC₅₀ = 15 nM).

A cell-permeable, ATP-competitive, and reversible indolocarbazole derivative that acts as a potent and selective inhibitor of checkpoint kinase (Chk1) in vitro. It inhibits Chk1 phosphorylation of cdc25C with an IC₅₀ of 15 nM. However, SB-218078 is a much weaker inhibitor of Cdc2 (IC₅₀ = 250 nM) and PKC (IC₅₀ = 1 µM).

Cell permeable: yes

Primary Target
Chk1

Product competes with ATP.

Reversible: yes

Target IC₅₀: 15 nM against Chk1 phosphorylation of cdc25C; 23 nM, 5.6 nM, 16 nM, against CDK1, CDK2, CDK4, respectively

Packaged under inert gas

Toxicity: Standard Handling (A)

Following reconstitution aliquot and freeze (-20°C). Stock solutions are stable for up to 6 months at -20°C.

Zhao, B., et al. 2002. J. Biol. Chem.277, 46609.
Jackson, J.R., et al. 2000. Cancer Res.60, 566

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany