Along with the oxoaporphine alkaloid liriodenine, a new oxoaporphine alkaloid lanuginosine and a new noraporphine alkaloid michelanugine have been isolated from the trunk bark of Michelia lanuginosa. They have been shown to possess 1,2-methylenedioxy-9-methoxy-7-oxoaporphine and 1,2-methylenedioxy-9-methoxy-7-hydroxynoraporphine structures through chemical and spectral studies. The stereostructure of michelanugine (6a-H as β and 7-OH as α) has been elaborated with the help of PMR and rotational data. © 1975.