Coumestanes estrogenic activities

Coumestans, such as coumestrol, are found in high concentrations in alfalfa and clover and have been recognized, along with formononetin, as the cause of infertility in grazing herbivores. Whereas coumestrol acts as an estrogen mimic directly, formononetin has to be metabolized to the estrogenically active compounds diadzein, equol, or >-demethylangolensein. 

One concern raised about isoflavones, coumestanes, and stilbenes is that they have estrogenic activities. Indeed, some of the health benefit claims for these compounds... 

Coumestans represented by 321 are an oxygenated class of aromatic natural products, which have phytoalexin and estrogenic activities. From the biogenetic point of view, 321 will be formed from two units, 4-hydroxycoumarin (322) and catechol. Thus, the first synthesis of 321 was carried out by an electrochemical method. Catechol was initially oxidized to o-quinone, which was attacked by 322 to afford 321 in 95% yield (Scheme 69). ... 

Isoflavones (2), lignans (3 ) such as dibenzylbutane (3) and coumestans (4) could express both a wide range of estrogens (1) like-hormonal and non-hormonal activities. Therefore, it is expected that the human daily diets with... 

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