Dienone-phenol rearrangement of dienone (II) with concentrated sulfuric acid gave a cularine-type compound, 9-hydroxy-5, 6, 10-trimethoxy-1-methyl-1, 2, 3, 12, 12a-pentahydrobenzoxepino [2, 3, 4-i, j] isoquinoline (III), whose structure was assigned by spectroscopic method and its alternative synthesis of III from 1-(2-bromo-4-hydroxy-5-methoxybenzyl)-1, 2, 3, 4-tetrahydro-8-hydroxy-6, 7-dimethoxy-2-methylisoquinoline (XI). Moreover, this paper described the preparation of XI.