3-Methyl-19-methyleneandrosta-3,5-dien-17β-ol is a synthetic, steroidal estrogen and a selective agonist of the ERβ. It was discovered serendipitously and was the lead compound among a series of androsta-3,5-dienes as ERβ ligands. Its affinity (IC50) for the ERβ was found to be 9 nM and it showed 62- and 160-fold binding selectivity for this receptor over the  and the ERα, respectively. The EC50 of the compound for the ERβ was found to be 69 nM and its intrinsic activity was 92% (relative to that of estradiol). As such, it is a potent ERβ agonist with high affinity and selectivity.

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Secondary alcohols
Androstanes
Selective ERβ agonists
Synthetic estrogens