Table 1.

Selected SAR for the initial analogues of the HTS hits 1 and DBeQ.

					IC50 [μm]a
Compd	R1	R2	R3	R4	ATPase	UbG76V–GFP
2	2-chlorophenyl	benzyl	H	H	1.2±0.6	8±3
3	3-nitrophenyl	benzyl	H	H	5.9±3	4.0±1.6
4	phenyl	benzyl	H	7-Cl	70±24	12±4
5	p-tolyl	benzyl	H	7-Cl	39±13	24±5
6	piperidnyl	benzyl	H	H	26±4	7.3±2
7	morpholinyl	benzyl	H	H	23±6	36±9
8	phenyl	benzyl	Me	H	49±17	17±5
9	N-aminophenyl	phenyl	H	H	2.6±0.8	7.2±1
10b	N-aminophenyl	benzyl	H	H	2.3±1	3.1±0.4
11	N-amino(3-chlorophenyl)	benzyl	H	H	0.48±0.16	7.8±1.3
12	N-amino(3-chlorophenyl)	4-fluorobenzyl	H	H	1.5±0.3	5.7±1.3
13	N-amino(4-methoxybenzyl)	benzyl	H	H	3.0±0.5	1.3±0.2
14	N-aminobenzyl	benzyl	H	8-OMe	0.6±0.06	10±2

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

^bScreened as the HCl salt.