Synthesis of (±)-isomedicarpin, (±)-homopterocarpin and tuberostan: a novel entry of ‘hydrogenative cyclisation’ into pterocarpans

Abstract

An efficient three-step synthesis of the coumestan, tuberostan (1), from the benzyloxyisoflavone (2) is described. The synthesis involves a single-step ‘hydrogenative cyclisation’ of the isoflavone (2) to the pterocarpan, (±)-isomedicarpin (5)