Construction of benzofuranone library via a metal-free, one-pot intermolecular condensation, and their application as efficient estrogen receptor β modulators.

Facile synthesis of benzofuranone was achieved through a metal-free, one-pot intermolecular condensation between α-hydroxy aryl ketones and resorcinol derivatives. A library of 20 compounds with moderate to good overall yields was prepared. These compounds showed strong binding toward estrogen receptors along with good selectivity for ERβ (>190-fold over ERα). Anti-proliferative activity on DU-145, U-87, and MCF-7 cells gave inhibition IC50 values in the low μM range, which suggested the promising potential therapeutic applications of these new classes of benzofuranones.