A novel isoindole alkaloid named oleraisoindole (1), together with six known compounds, 7'-ethoxy-trans-feruloyltyramine (2), N-trans-feruloyltyramine (3), N-trans-feruloyl-3-methoxytyramine (4), N-trans-p-coumaroyltyramine (5) aurantiamide (6) and ferulic acid methyl ester (7) were isolated from Portulaca oleracea L. Compounds 2 and 7 were isolated for the first time from this plant. Compound 1 was identified using spectroscopic methods including HR-ESI-TOF-MS, 1D-NMR, 2D-NMR. It was tested in a nitric oxide (NO) inhibition assay and was shown to inhibit NO production in RAW 264.7 cells induced by LPS.
Keywords: Portulaca oleracea L.; alkaloid; nitric oxide (NO).