The first example ot the benzo[b]pyrimido[4,5-f]azocine king system

Base catalyzed cyclization of ethyl 4-2-(2-amino-4,5-dimethoxyphenyl)ethyl]-2-phenylpyrimidine-5-carboxylate, derived from ethyl 4-methyl-2-phenyl-5-pyrimidinecarboxylate and 3,4-dimethoxy-6-nitrobenz-aldehyde, gave 5,6-dihydro-8,9-dimethoxy-3-phenylbenzob]pyrimido4,5-f]azocine-12(11H)-one, the first reported example of this ring system.