CHEMBL5737776

Affinity Assay: hAR-LBD (633-919) was cloned into pGex4t.1. Large scale GST-tagged AR-LBD was prepared and purified using a GST column. Recombinant AR-LBD was combined with [3H]mibolerone (PerkinElmer, Waltham, Mass.) in buffer A (10 mM Tris, pH 7.4, 1.5 mM disodium EDTA, 0.25 M sucrose, 10 mM sodium molybdate, 1 mM PMSF) to determine the equilibrium dissociation constant (Kd) of [3H]mibolerone. Protein was incubated with increasing concentrations of [3H]mibolerone with and without a high concentration of unlabeled mibolerone at 4° C. for 18 h in order to determine total and non-specific binding. Non-specific binding was then subtracted from total binding to determine specific binding and non-linear regression for the ligand binding curve with one site saturation was used to determine the Kd of mibolerone. The results of this assay are reported as Ki values (nM) in Table 1 in the column labeled ‘wt AR Binding (Ki(left))’. As discussed above and is apparent from Table 1, there is a poor correlation between AR-LBD affinity and SARD activity. E.g., see in vitro SARD activity for 1002, 1005, 1015, 1019, 1020, and 1022 despite no binding affinity for the LBD.