Publication Date:
2015-07-15
Description:
A new tricyclic alkaloid named portulacatone ( 1 ), i.e. , 5,6-dihydro-8,9-dihydroxy-11 H -pyrrolo[2,1- b ] [3]benzazepin-11-one, together with eight known compounds, methyl 4-hydroxyphenylacetate ( 2 ), p -hydroxybenzaldehyde ( 3 ), vanillin ( 4 ), protocatechualdehyde ( 5 ), p -hydroxybenzoic acid ( 6 ), iseluxine ( 7 ), oleracein E ( 8 ), and (+)-( R )-feruloyl malate ( 9 ) were isolated from aerial parts of Portulaca oleracea L. Their structures were elucidated based on spectroscopic analyses. Among them, compounds 1 – 7 and 9 were isolated from this medicinal plant for the first time. Compounds 1 and 7 showed dose-dependent scavenging activities against DPPH (2,2-diphenyl-1-picryl-hydrazyl) free radical, with EC 50 values of 14.36 μ M and 9.98 μ M , respectively, more potent than the natural antioxidant vitamin C ( EC 50 20.72 μ M ).
Print ISSN:
0018-019X
Electronic ISSN:
1522-2675
Topics:
Chemistry and Pharmacology
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