Studies on the constituents of bocconia cordata. IV. Transformation of sanguinarine into bocconine

Nitration of ethoxysanguinarine with equimolar potassium nitrate and sulfuric acid, followed by treatment with sodium hydroxide and methanol, gives 10-nitromethoxysanguinarine. Successive hydrogenation, diazotization and methanolysis convert 10-nitromethoxysanguinarine into bocconine.