A potent, non-selective inhibitor of PKA with an IC50 value of 0.14 µM (Ki = 48 nM) that is widely used to disrupt PKA signaling; inhibits S6K1, MSK1, ROCK-II, PKBa, and MAPKAP-K1b with IC50 values of 0.08, 0.12, 0.27, 2.6, and 2.8 µM, respectively.