(±)-DIONCOPHYLLACINE A, A NAPHTHYLISOQUINOLINE ALKALOID WITH A 4-METHOXY SUBSTITUENT FROM THE LEAVES OF TRIPHYOPHYLLUM PELTATUM*

Abstract The isolation and structure elucidation of rac -dioncophyllacine A from the leaves of Triphyophyllum peltatum , is described. Unlike all other naphthylisoquinoline alkaloids, this fully dehydrogenated representative has an additional methoxy group at C-4, the position of which is deduced from NOE results. Dioncophyllacine A has a 7,1′-site of the biaryl axis, as in dioncophylline A. Its constitution is confirmed by an X-ray structure analysis, which shows that the crystalline form of this new alkaloid is racemic.