Table 1. σRs Binding Affinities for 13–16, 20–22, and 24.

	Ki (nM) ± SDa
compound	σ1R	σ2R	Ki σ2/Ki σ1
8b	5.7 ± 0.1	2,460 ± 85	432
13	18.1 ± 0.44	1,162 ± 40	64
14	13.3 ± 0.22	1,644 ± 37	124
15	1.6 ± 0.05	1,418 ± 18	886
16	11.3 ± 0.26	3,968 ± 130	351
20	102 ± 0.6	4,367 ± 33	43
21	8.8 ± 0.22	3,253 ± 40	370
22	145 ± 0.5	23,190 ± 146	160
24	6.1 ± 0.1	2,583 ± 54	423
haloperidol	1.6 ± 0.1	17.6 ± 0.1	11

^aK_i values are expressed as mean  ±  SD of three independent experiments.

^bData from ref (44).