Acetogenic isoquinoline alkaloids - Part 98 - Dioncophyllinol D, the first 4-hydroxylated naphthylisoquinoline alkaloid, from the leaves of Triphyophyllum peltatum

The first isolation of a 4-hydroxylated naphthylisoquinoline alkaloid, dioncophyllinol D (5), from the leaves of Triphyophyllum peltatum (Dioncophyllaceae), is described. Its structural elucidation is based mainly on NMR, degradative, and computational methods. With its rare 7,8'-linkage between the isoquinoline and naphthalene parts, 5 is one of the very few naphthylisoquinolines without a stable configuration at the biaryl axis.