Alkaloids from marine organisms, Part 5. Biomimetic total synthesis of lamellarin L by coupling of two different arylpyruvic acid units.

Reaction of the ethyl 3-arylpyruvate 5a with the methyl 2-bromo-3-arylpyruvate 6b in the presence of the 2-arylethylamine 4 afforded the pyrrole derivative 10, which could be transformed into lamellarin L (1) in five steps. The synthesis proceeds with 38% overall yield and mimics the probable biosynthesis of these marine alkaloids.