A nitrogen-containing 3-alkyl-1,4-benzoquinone and a gomphilactone derivative from Embelia ribes

An unusual nitrogen-containing 3-alkyl-1,4-benzoquinone derivative, N-(3-carboxylpropyl)-5-amino-2-hydroxy-3-tridecyl-1,4-benzoquinone (1), and a gomphilactone derivative, 5,6-dihydroxy-7-tridecyl-3-[4-tridecyl-3-hydroxy-5-oxo-2(5H)-furylidene]-2-oxo-3(2H)-benzofuran (2), together with 14 known compounds, as well as the common plant metabolites sitosterol and daucosterol, were isolated from the ethanolic extract of the roots of Embelia ribes. Their structures were elucidated by means of spectroscopic methods. Cytotoxicities of the purified compounds were tested.