Table 3.

Docking interactions, calculated free energy values and in vitro inhibition values on LTopIB for selected terpenylquinones.

Compd.	H-bonds	Other binding contactsa				ΔG (kcal/mol)b	IC50 (μM)
		A	B	C	D
1	Arg190	+	–	+	+	−9.5	23.5 ± 1.3
2	-	+	–	+	–	−8.8	13.5 ± 0.6
4	-	+	–	+	+	−10.6	50.1 ± 5.0
6	Arg190	–	–	+	–	−10.2	73.5 ± 3.4
12	Arg190	+	–	+	–	−9.6	10.7 ± 2.2
13	Arg190	+	–	+	–	−10.2	91.8 ± 8.2
14	Arg190	+	–	+	–	−10.3	>100
15	Arg190	+	–	+	–	−10.3	>100
17	Arg190, Asn221	+	+	+	+	−11.6	>100
21	Arg190	–	–	+	–	−8.7	57.9 ± 4.1
25	Arg190 (dual)	–	+	–	+	−11.5	41.4 ± 7.4
CPT	Arg190, Asp353	–	+	–	+	−12.2	2.8*

^aEnzyme fragments involved in LTopIB - quinone contacts: region A: Ala177-Lys200; region B: Thr217-Asn221; region C: Met250-Pro257; region D: Lys352-Asp353. See Suppl. Material, Table S1 and Fig. S1, for more detailed information.

^bBest free energy values and best experimental results are in bold for better comparisons. *CPT IC₅₀ was obtained from reference (Roy et al., 2008).