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Updated: Sep 21, 2026

Quantifying Agonist Activity at G Protein-coupled Receptors
Published on: December 26, 2011
[The absolute configurations and biological activities of alpha- and beta-anordrins]
Abstract:
The molecular structures and absolute configurations of alpha- and beta-anordrins are reported. Animal experiments showed that pure alpha-epimer possessed high anti-implantation and anti-early pregnancy effects, but the pure beta-epimer exhibited very low effects at the same dose. MNDO program was applied for the optimization of the configurations of epimers to establish the isolated molecular configurations and calculate the quantum chemical indexes. The results showed that the configurations and the differences of action field in three-dimensions of alpha- and beta-epimer are probably the factors that the alpha-epimer exhibited biological activity.
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