Practical and efficient entry to isoflavones by Pd(0)/C-mediated Suzuki–Miyaura reaction. Total synthesis of geranylated isoflavones

A scalable synthesis of isoflavones taking advantage of the Suzuki–Miyaura reaction catalyzed by Pd(0)/C is described. The approach developed has been extended to the total synthesis of 7-O-geranylformononetin, griffonianone D, and conrauinone D, which did not display cytotoxicity against human HeLa carcinoma cells. In addition, this study established unambiguously the absolute configuration of natural griffonianone D.