[New total synthesis of derrusnine].
The thermal condensation of diethyl 3,4-methylenedioxyphenylmalonate with 3,5-dimethoxyphenol (di-O-methylphloroglucinol) leads to the corresponding 3-(3,4-méthylenedioxyphenyl)-4-hydroxy-5,7-dimethoxycoumarine which is methylated further into derrusnine.