Four alkaloids were isolated from Portulaca oleracea L., including two new compounds, 2-(4-amino-6-hydroxy-1,6-dihydropyrimidin-5-yl)-5-(hydroxymethyl)tetrahydrofuran-3,4-diol, named Olerapyrimidine (1) and (2 R,3S,4S,5R,6S)-2-(hydroxymethyl)-6-((6-hydroxypyridin-3-yl)oxy)tetrahydro-2H-pyran-3,4,5-triol, named Olerapyridine (2), and two known compounds including 1H-imidazole (3) and (5S, 6 R, 7S, 8 R)-5-amino-(2Z,4Z)-1,2,3-trihydroxybuta-2,4-dienyloxy-pentane-6,7,8,9-tetraol (4) from P. oleracea for the first time. Their structures were determined by spectroscopic methods, including UHPLC-ESI-Q-TOF/MS, 1D and 2D NMR spectra. Both Olerapyrimidine and Olerapyridine at 20 μM could inhibit the inflammatory factors, IL-1β and TNF-α in the RAW 264.7 cells induced by LPS.
Keywords: Portulaca oleracea L; alkaloid; anti-inflammatory.