Iseluxine: A Novel Isoquinolinone Alkaloid from Isei a luxurians

A novel isoquinolinone alkaloid, iseluxine (1), has been isolated from the epigeal parts of Iseia luxurians (Moric.) O’Donell (Convolvulaceae), a climber indigenous to the tropical Americas. Structural elucidation was achieved by HRM S, H NMR, C NMR , and HMBC spectroscopy. N- and / or O-m ethyl derivatives of 1 are already known from certain Magnoliidae families, e.g., the Fumariaceae, the Lauraceae, or the Papaveraceae. Iseluxine, the “missing link” in the biosynthesis of these methyl derivatives from dopamine, is the first isoquinolinone alkaloid characterized by a catechol substructure.