Background:

BX-517 is a potent and selective inhibitor of PDK1 that binds to the ATP binding pocket

of the protein (IC50 = 6 nM). BX-517 also blocks activation of Akt in tumor cells with 10-fold more potent (IC50 = 0.1–1.0 μM) than its analogs tested at the highest dose tested (10 μM). [1] The phosphoinositide-dependent kinase-1 (PDK1) is a Ser/Thr kinase that is a crucial activator of a range of protein kinases in the AGC kinase super-family that play key roles in the progression of cancer and for the activation of Akt, S6 kinase, and protein kinase C. [2]

参考文献:
1.  Islam I, Brown G, Bryant J et al. Indolinone based phosphoinositide-dependent
kinase-1 (PDK1) inhibitors.  Part 2: optimization of BX-517. Bioorg Med Chem Lett.
2007 Jul 15;17(14):3819-25. 
2.  Islam I, Bryant J, Chou YL etc. Indolinone based phosphoinositide-dependent kinase-1 (PDK1)
inhibitors.  Part 1: design, synthesis and biological activity. Bioorg Med Chem Lett. 2007 Jul 15;17(14):3814-8.