A total synthesis of lamellarins U and A3 is described. The synthesis features interruption of a halogen dance reaction of a metalated α,β-dibromopyrrole. The pyrrolylmagnesium reagent, generated by deprotonative metalation using (TMP)MgCl·LiCl (TMP: 2,2,6,6-tetramethylpiperidide) as base, was transmetalated to the corresponding organozinc species without causing the halogen dance reaction, which underwent a Negishi coupling to incorporate an aryl group onto the pyrrole ring. The arylated α,β-dibromopyrrole was then converted into lamellarins U and A3 through an α-selective halogen–magnesium exchange followed by carboxylation and subsequent palladium-mediated cyclization. The late-stage introduction of another aryl group was performed using a Kosugi–Migita–Stille coupling to provide lamellarins U and A3.

A formal synthesis of dictyodendrin B is described. Regiocontrolled functionalization of the α,β-dibromopyrrole derivative provided the fully substituted pyrrole bearing an indole moiety. Subsequent reductive cyclization using a combination of sodium dispersion and triethylsilyl chloride enabled the formation of the benzene ring in the characteristic tetracyclic pyrrolo­[2,3-c]­carbazole skeleton, while the ethyl ester remained untouched. Further chemical transformation of the ester moiety and functional group manipulation completed the formal synthesis of dictyodendrin B.