Synthesis of the novel isoquinoline enamide alkaloid polycarpine

The synthesis of the novel enamide isoquinoline alkaloid polycarpine, (Z)-1-(2′-hydroxy-3′,4′-dimethoxy-benzylidene)-3,4-dihydro-6,7-dimethoxy-2-(1H)isoquinolinecarboxaldehyde, proceeding from commercially available 2′,3′,4′-trimethoxyacetophenone in seven steps is described. The O-methyl and O-benzyl derivatives were also obtained.