Hong_2019_J.Nat.Prod_82_3221

Nine new alkaloids, (+)-1, (-)-1, 2, (+)-3, (-)-3, and 4-7, along with five known compounds (8-12), were obtained from the branches and leaves of Elaeocarpus angustifolius. The alkaloids were structurally characterized by NMR and MS data. The absolute configurations of (+)-1, (-)-1, (+)-3, and (-)-3 were determined by comparing their experimental and computed electronic circular dichroism spectra. (+/-)-8,9-Dehydroelaeocarpine (5), (+/-)-9-epielaeocarpine cis-N-oxide trifluoroacetate (6), and (+/-)-elaeocarpine trifluoroacetate (9) exerted weak inhibitory activities against butyrylcholinesterase with IC50 values of 39, 29, and 35 muM, respectively, while that of tacrine, the positive control, was 0.07 +/- 0.01 muM. This is the first report of the cholinesterase inhibitory activities of Elaeocarpus alkaloids.