Synthesis of an Estrogen Receptor-β Agonist

Significance

The target molecule was a candidate for hormone replacement therapy aimed at a treatment for the symptoms of menopause with reduced risk of developing breast cancer, deep vein thrombosis, stroke and cardiovascular disease. The short multikilogram synthesis depicted features a phase-transfer-catalyzed conjugate addition (C → E) mediated by the cinchonine-derived catalyst D. The synthesis involves only six isolated intermediates and avoids chromatographic purification.