A New Alkaloid from Portulaca oleracea and Its Anti-Inflammatory and Antioxidant Activities

Abstract

A new alkaloid, (S)-1-methyl-2-nitroso-1,2,3,4-tetrahydroisoquinoline-6,7-diol (1), named oleraisoquinoline A, and 9 known compounds, iseluxine (2), oleracrylimide E (3), oleracrylimide A (4), oleracrylimide B (5), chrysoeriol (6), 2-(2-hydroxyphenyl)-5,7-dimethoxychroman-4-one (7), portulacanone C (8), portulacanone D (9), and 2,2′-dihydroxy-4′,6′-dimethoxychalcone (10), were obtained from P. oleracea, in which, compounds 6, 7 were isolated from the plant for the first time. The structure of compound 1, identified by UHPLC-ESI-Q-TOF/MS, 1D, 2D NMR, and CD, presented remarkable anti-inflammatory and antioxidant activities, as also did compound 2, while 6 presented antioxidant activities.