Studies on the Alkaloids of Melicope confusa (MERR.) LIU

From the fresh leaves of Formosan Melicope confusa (MERR). LIU, skimmianine (II), kokusaginine (IV), and a new furoquinoline-type alkaloid, confusameline, were isolated. The new alkaloid, confusameline, occurs as light brownish needles, mp 239-240°, and its methylation with diazomethane gives evolitrine (XIV). By the comparison of signal positions of methoxyl groups in the nuclear magnetic resonance (NMR) spectrum of the O-ethyl compound (XV), obtained by ethylation with diazoethane, and the NMR spectra of several known furoquinoline-type alkaloids which have already been reported (Table I), the structure of confusameline was proposed as formula XIII.