Arechuines A-D, arecoline alkaloids from the peels of Areca catechu L.

Four novel arecoline alkaloid atropisomers, arechuines A-D (1 - 4), were obtained from the peels of Areca catechu L. Their structures were elucidated by UV, IR, MS and NMR spectra. The absolute configurations of (+)/(-)-4 were determined by comparing the experimental and calculated ECD spectra. Compounds 1 - 4 were evaluated for their neuroprotective effects in glutamate-induced HT22 cell and 3 revealed potent neuroprotective effects at 10 μM. These are the first reported arecoline alkaloid atropisomers isolated from A. catechu.