Synthesis of Isoflavanes and Intermediates Thereof

A method for enantioselective production of equol from daidzein, comprising the steps:

• (a) selectively reducing the daidzein, which may have protective groups covalently attached to the hydroxy groups, such that the 4-keto group of the daidzein is converted into a 4-hydroxy group, and the 2,3-double bond of the daidzein is converted to a 2,3-single bond, thereby obtaining a 4-hydroxy intermediate, and
• (b) reacting the 4-hydroxy intermediate with a chiral reagent, such that a chiral group is covalently attached to the C4-position of the 4-hydroxy intermediate, thereby obtaining a chiral intermediate, and
• (c) reacting the chiral intermediate with an amine reagent, such that an amine group is covalently attached to the C4-position, whereas the chiral group is removed from the C4-position, thereby obtaining an amine intermediate.