Abstract: | The Structure of the Alkaloid Juliprosopine from Prosopis juliflora A. Dc. A new alkaloid, juliprosopine, has been isolated from Prosopis juliflora A. Dc. (Leguminosae), for which structure 1 is proposed. The piperidine moiety could be elucidated on the basis of spectroscopic data (MS., 1H-NMR., 13C-NMR.) of juliprosopine and the derivatives 2–4 . The central hexahydroindolizine part and its substitution pattern has been determined mainly on the bases of the Hofmann-degradation product 11 , which yielded the hydrogenation products 13 and 14 . By ozonolysis 11 was converted to 16 and 18 . It is proposed that juliprosopine was built up in nature by two ‘monomeric’ Prosopis alkaloids and one dihydropyrrol unit. |