Total Syntheses of Pyocyanin, Lavanducyanin, and Marinocyanins A and B.

Total syntheses of pyocyanin, lavanducyanin, and marinocyanins A and B have been accomplished. The N-substituted phenazin-1-one skeleton, a common framework of these natural products, was constructed through the oxidative condensation of pyrogallol with N-substituted benzene-1,2-diamine under an oxygen atmosphere in a single step. Regioselective bromination with N-bromosuccinimide at the C-2 position of N-alkylated phenazin-1-ones afforded brominated natural products.