Table 3. . Protein kinase C inhibitors.

No.	Structure	Inhibitor class	Publication year	Activity
27		Natural inhibitor (Staurosporine)	1977, first isolated; 1986, the inhibitory activity against PKC was revealed	PKC (IC50 = 2.7 nM)
28		Semisynthetic (K-252 a)	1986	IC50 = 18–25 nM
29		Semisynthetic (K-252b)	1986	IC50 = 20 nM
30		Semisynthetic, 7-oxo Staurosporine (RK –1409)	1992	IC50 ≈ 1 nM
31		Natural (Calphostin C)	1989	IC50 = 0.05 µM
32		Synthetic (AEB071)	2009	PKC-α (IC50 = 2.1 nM) PKC-ϵ (IC50 = 6.1 nM)
33		Synthetic	2011	PKC-α (IC50 = 829 nM) PKC-ϵ (IC50 = 5 nM)
34		Synthetic	2011	PKC-βII (Ki = 29 nM)
35		Flosequinan-selective PKC inhibitor	1992	–
36		Ruboxistaurin	2006	PKC-βI (IC50 = 4.7 nM) PKC-βII (IC50 = 5.9 nM)

PKC: Protein kinase C