(Rac)-Acolbifene (EM-343; (Rac)-EM-652)是一种含有哌啶环的化合物，具有抗雌激素和雌激素双重活性，它是雌激素受体拮抗剂EM652的外消旋形式，其相对结合亲和力高达380，并展现出良好的药理作用。

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