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A concise synthesis of topsentin A (R-1 = R-2 = H) and nortopsentins B (R-1
= Br, R2 = H) and D (R-1 = R-2 = H) is described from oxotryptamine 5 via
reduction of acyl cyanide 4, Regiospecific bromination of a cyanoindole aff
orded 6-bromo-3-cyanoindole (10) as the major product.