7,8-Demethylene sanguinarine

Finally, Spath and Kuffner (39) succeeded in showing that the alkoxyl groups in chelerythrine and sanguinarine occupy the same positions. For this purpose the feebly basic dihydro bases of Karrer (36), who regarded them as non-basic, were demethylenated with sulfuric acid in the presence of phloroglucinol. The dihydroxy compound from chelerythrine and the tetrahydroxy compound from sanguinarine were methylated with diazomethane, and in both cases the same tetramethoxydihydro-iV-methyl-a-naphthaphenanthridine (XVIII) was obtained. 

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