Synthesis of two lamellarin derivatives, that is, naphthoquinone-fused pyrrolo[2,1-a]isoquinoline and tridemethoxy lamellarin D was reported. The former was synthesized by Lewis acid-catalyzed oxidative cyclization of 6,7-dimethoxynaphthalene-1,4-dione and papaverine to form the pentacyclic scaffold. The latter was prepared via basemediated Grob coupling of 1-methylisoquinoline and 7methoxy-3-nitrocoumarin as a key step to construct the lamellarin skeleton.

Construction of the coumarin-fused pyrrolo[2,1a]isolquinoline skeleton was realized through a four-component reaction between isoquinoline, ethyl bromoacetate, ohydroxybenzaldehyde and nitromethane. This methodology was further extended to the synthesis of lamellarin D trimethyl ether and a formal synthesis of lamellarin D. The controlled demethylation of lamellarin D trimethyl ether yielded dihydroxy and tetrahydroxy lamellarin analogues regioselectively.