Table 3:

Combinations of optimal substituents creats more potent Hsp70 inhibitors

Compd	R1	R3	MCF-7 IC50/μM	MDA-MB-231 IC50/μM	MEF IC50/μM
JG-98	5-Cl		0.71 ± 0.22	0.39 ± 0.03	4.2 ± 1
48	4-CH3		0.089 ± 0.006	0.18 ± 0.01	1.4 ± 0.1
49	5-CH3		0.064 ± 0.005	0.077 ± 0.009	0.75 ± 0.05
50	4-OCH3		0.16 ± 0.02	0.16 ± 0.01	2.2 ± 0.1
51	5-OCH3		0.070 ± 0.003	0.053 ± 0.005	0.70 ± 0.01
52	5-isopropyl		0.090 ± 0.005	0.21 ± 0.01	0.48 ± 0.02
53	5-OCH3		0.048 ± 0.003	0.033 ± 0.005	0.66 ± 0.01
54	5-SCH3		0.15 ± 0.01	0.13 ± 0.01	0.75 ± 0.05
55	5-OCH3		0.076 ± 0.005	0.062 ± 0.006	0.77 ± 0.03
56	5-CH3		0.071 ± 0.006	0.082 ± 0.010	0.96 ± 0.03
57(JG-345)	5-CH2CH3		0.049 ± 0.003	0.046 ± 0.006	1.0 ± 0.1
58	4-CH3		0.088 ± 0.008	0.054 ± 0.006	0.55 ± 0.03
59	5-CH2CH3		0.093 ± 0.007	0.10 ± 0.01	0.30 ± 0.10
60(JG-294)	5-Br		0.10 ± 0.01	0.18 ± 0.01	3.5 ± 0.4
61	5-CH2CH3		0.11 ± 0.01	0.10 ± 0.01	1.4 ± 0.06