Table 1.

Structure–activity relationships for IOX1 (1) and its ester derivatives 2–7

Compd	R1	R2	CC50[a] [μm]	EC50[b] [μm]	IC50[c] [μm]
1	H	H	>300	100.0	0.6
2	CH3	H	10	50.0	10.7
3	CH2CH3	H	66	>100	14.9
4	(CH2)3CH3	H	50	22.0	5.0
5	(CH2)7CH3	H	>300	3.8	3.9
6	CH3	COCH3	29	>100	10.5
7	CH2OCOC(CH3)3	CH2OCOC(CH3)3	17	–	>100

[a] CC₅₀ values derived from HeLa cell viability assays. [b] EC₅₀ values derived from immunofluorescence assays of KDM4A activity in HeLa cells. [c] IC₅₀ values derived from AlphaScreen assays of isolated KDM4C. Data represent the mean of n≥3 replicates (Figures S1, 2, and 5 in the Supporting Information).