Table 2.

Relative Binding Affinity (RBA) of 7-Thiabicyclic-7-oxide Analogs for ERα and ERβ^a.

Entry	Compound	ERα	ERβ	α/β ratio
1	10a	0.956 ±0.16	0.110 ±0.03	8.33
2	10b	0.074 ± 0.002	0.080 ± 0.015	0.925
3	10c	0.077 ± 0.01	0.071 ±0.02	1.08
4	10d	0.017 ±0.005	0.013 ±0.001	1.31
5	10e	0.022 ± 0	0.048 ± 0.005	0.458
6	11a	8.11 ±1.8	0.348 ± 0.01	23.3
7	11b	0.741 ±0.18	0.091 ± 0.02	8.14
8	11c	3.53 ± 0.45	0.138 ±0.04	25.6
9	11d	2.49 ± 0.31	0.227 ± 0.03	11.0
10	11e	2.21 ± 0.60	0.070 ± 0.02	31.6
11	11f	2.18 ± 0.65	0.080 ± 0.02	27.2
12	11g	2.13 ±0.36	0.083 ± 0.02	25.7
13	11h	3.37 ± 0.22	0.297 ± 0.08	11.3
14	11i	1.30 ±0.37	0.088 ± 0.021	14.8
15	11j	0.998 ± 0.22	0.180 ±0.05	5.54
16	11k	2.21 ± 0.48	0.812 ±0.06	2.72
17	11l	0.016 ±0.002	0.014 ±0.004	1.14
18	12a	3.49 ± 0.47	0.014 ±0.004	249
19	12b	0.310 ±0.05	0.021 ± 0.006	14.8
20	12c	2.48 ±0.13	0.010 ±0.003	248
21	12d	1.18±0.18	0.022 ± 0.005	53.6
22	12e	0.516 ±0.14	0.014 ±0.004	36.8
23	12f	0.236 ± 0.07	0.019 ±0	12.4
24	12g	0.109 ±0.003	0.009 ± 0.001	12.1
25	12h	0.009 ± 0.002	0.007 ± 0.001	1.28
26	12i	0.026 ± 0.008	0.019 ±0.005	1.37
27	13	0.005 ± 0.001	0.008 ± 0.001	0.62
28	14	0.005 ± 0.001	0.011 ±0.001	0.45
29	15	0.035 ± 0.009	0.055 ± 0.001	0.64
30	1a	0.572 ± 0.12	1.69 ± 0.45	0.338
31	1b	2.16 ±0.54	4.86 ± 1.3	0.444
32	1c	0.793 ± 0.05	0.306 ± 0.01	2.59

^aRelative binding affinity (RBA) values are determined by competitive radiometric binding assays and are expressed as IC₅₀^estradiol/IC₅₀^compound × 100 ± the range or standard deviation (RBA, estradiol = 100%). In these assays, the K_d for estradiol is 0.2 nM on ERα and 0.5 nM on ERβ. For details, see the Experimental Section.