Constituents of Rhizoma nupharis. XXII. Structure of Nuphamine

A new alkaloid (I), C15H23O2N has been isolated from Nuphar japonicum DC. and named nuphamine. The compound (III) obtained by the catalytic reduction after the chlorination of I with thionyl chloride is completely in accordance with (-)-desoxynupharamine, derived from nupharamine (IX). By the catalytic reduction of I with palladium-carbon, dihydronuphamine (V), (-)-deoxynupharidine (VI-A) and allodeoxynupharidine (VI-B) were prepared. VI-A and VI-B were also prepared from V. Judging from these reactions and the nuclear magnetic resonance spectra, the structure of I has been determined to be presented by the fromula VIII. The steric chemical correlations among the alkaloids, (-)-desoxynupharidine (VI-A), (-)-nuphamine (VIII) and (-)-nupharamine (IX) isolated from Nuphar iaponicum have been also achieved.