Table 2.

Inhibition constants and IC₅₀ values obtained by kinetic inhibition and cytotoxicity studies of the most potent inhibitors DM96, DM151, DM109, and Curcumin II. The in-silico-determined binding free energies (kcal/mol) are also included.

Inhibitor	IC50 against DU-145 (μΜ)	IC50 against hGSTP1-1 (μΜ)	Variable Substrate	Type of Inhibition	Inhibition Constants (μΜ)	Experimental Binding Free Energies (kcal/mol)
DM96	8.60 ± 1.07	5.45 ± 1.08	CDNB	Purely mixed	Ki = 3.67 ± 0.35 Ki΄ = 4.97 ± 2.86	ΔGexp = −7.71 ΔG′exp = −7.52
			GSH	Partial mixed	Ki = 3.69 ± 1.00 Ki΄ = 1.45 ± 0.43	ΔGexp = −7.71 ΔG′exp = −8.29
DM151	44.59 ± 1.08	11.17 ± 1.03	CDNB	Purely non-competitive	Ki = 9.55 ± 2.36	ΔGexp = −7.12
			GSH	Purely non-competitive	Ki = 5.79 ± 1.21	ΔGexp = −7.43
DM109	46.15 ± 3.68	19.53 ± 1.04	CDNB	Purely non-competitive	Ki = 20.12 ± 5.27	ΔGexp = −6.66
			GSH	Purely non-competitive	Ki = 35.12 ± 5.69	ΔGexp = −5.96
Curcumin II	48.52 ± 1.09	37.72 ± 1.02	CDNB	Partially mixed	Κi = 3.99 ± 1.80 Ki΄ = 2.36 ± 1.37	ΔGexp = −7.66 ΔG′exp = −7.98
			GSH	Partially mixed	Κi = 68.02 ± 14.60 Ki΄ = 52.83 ± 12.25	ΔGexp = −5.91 ΔG′exp = −6.07