Table 3.

Effective anthraquinones with a protein kinase CK2 inhibitor activity (adapted from Meggio et al. [218]).

Name	Structure	IC50 (µM)—Ki (µM)
Emodin (3-methyl-1,6,8-trihydroxyanthraquinone)		Ki = 1.85
1,8-dihydroxy-4-nitro-anthracene-9,10-dione		IC50 = 0.30; Ki = 0.78
1,8-dihydroxy-3-methyl-4-nitro-anthracene-9,10-dione		IC50 = 0.30; Ki = 0.95
1,8-dihydroxy-4,5-dinitro-anthracene-9,10-dione		IC50 = 0.30
1,4-dihydroxy-5,8-diamino-anthracene-9,10-dione		IC50 = 0.30; Ki = 0.42
1-bromo-4,5-dihydroxy-8-nitro-anthracene-9,10-dione		IC50 = 0.40
1,4,5-trihydroxy-8-(2-bromoacetamido)-anthracene-9,10-dione		IC50 = 0.70