ISOQUINOLINE ALKALOIDS FROM ANCISTROCLADUS-TECTORIUS

Two new alkaloids were extracted from the bark of Ancistrocladus tecto rius, 6,8-dimethoxy-3-hydroxymethyl-1-methylisoquinoline and the napht hylisoquinoline, 4'-O-demethylancistrocladine, together with the known isoquinolines, 6,8-dimethoxy-1,3-dimethylisoquinoline and ,8-dimethox y-1,3-dimethyl-3,4-dihydroisoquinoline, which, however, have never bee n isolated from a natural source. The structures of the new alkaloids, as well as the absolute stereochemistry of 4'-O-demethylancistrocladi ne were established by spectroscopic means and chemical correlations.