Table 1.

Binding Affinity and Selectivity over α4β2 and α3β4 nAChR of a Series of Compounds Where 2-(Pyridine-3-yl)ethyl (R2–2 from Figure 2) Is Fixed in the R2 Position^a

compd	R	α3β4	α4β2	selectivity
4	S-benzyl	12348 ± 1861	771 ± 334	16
5	S-methyl	1026 ± 254	18 ± 3	57
6	S-isobutyl	18683 ± 2058	4964 ± 103	4
7	S-2-butyl	18107 ± 1529	863 ± 13	21
8	hydrogen	644 ± 17	58 ± 3	11
9	S-isopropyl	24487 ± 622	577 ± 25	42
10	S-3-propylguanidine	24043 ± 1073	1531 ± 30	16
11	S-4-hydroxylbenzyl	27420 ± 4396	1606 ± 41	17
12	S-2-(methylthio)ethyl	35590 ± 173	448 ± 14	79
13	R-hydroxymethyl	964 ± 193	13 ± 1	74

^aAll experiments are performed in duplicate or triplicate and repeated 2–3 times. Data are presented as the mean ± SEM.