Table 4:

Aromatic pyridazinones with extended basic group

	R	R’	BPTF Alpha Screen IC50 (μM)	L.E.
18 (BZ1)		Cl	0.067 ± 0.01	0.51
19		Cl	0.17	0.44
20		Cl	10	0.32
21		Br	0.036 ± 0.008	0.53
22		Cl	0.056 ± 0.01	0.45

AlphaScreen values were an average of two technical replicates, with N = 1 except for 18 (BZ1) which was an average of seven experimental replicates and 21–22 which were averages of three experimental replicates. Binding isotherms shown in Figure S4.