STUDIES ON THE SYNTHESIS OF DIMETHYI,4-HYDROXY -4'-METHOXY-5,6,5',6'-BISMETHYLENEDIOXYBIPHENYL-2,2'-DICAPBOXYLATE——AN ESSENTIAL METABOLITE OF DDB

摘要

This paper reports the total synthesis of dimethyl4-hydroxy-4’-methoxy-5,6,5’,6’-bismethylenedioxybiphenyl-2,2’-dicarboxylate(Ⅱ).Various conditions for bromination were tried to find the best one for synthesis of thekey intermediate compd 6.After Lllmann condensation of 6 with 8 and hydrogenolysis,the title compd Ⅱ was obtained.It was proved to be identical with the isolatedmetabolite of DDB by spectral data.