Table 3.

Selected SAR related to the optimization of ML241.

			IC50 [μm]a
Compd	R1	R2	ATPase	UbG76V–GFP
ML241	see Figure 3		0.11±0.03	3.5±0.4
31			1.1±0.2	10±1
32			2.9±0.2	27±3
33	OCH2CH2OH	benzyl	0.17±0.05	3.8±0.8
34	OCH2CH2OMe	benzyl	0.6±0.03	6.5±0.7
35	OCH2CH2NEt2	benzyl	0.4±0.08	5.3±0.6
36	4-methoxyphenyl	benzyl	1.1±0.1	9±1
37	n-butoxy	benzyl	2.63±0.7	28±3
38	methoxy	benzyl	0.2±0.02	3.3±0.4
39	OCH2CN	benzyl	0.4±0.08	7.7±0.7
40	methoxy	4-fluorobenzyl	1.9±0.4	3.7±0.6
41	methoxy	thiophen-2-ylmethyl	1.2±0.2	3±0.6
42	methoxy	cyclohexylmethyl	7.4±0.9	8.2±1
43	methoxy	2-hyrdoxylbenzyl	4.6±1	6±0.6

^aMeasurements were carried out in triplicate, and results are expressed as the mean ±SD.