Two new coumarins from the seeds of Solanum indicum

Abstract

Two new coumarins, (E)-2-(4-hydroxy-3-methoxybenzylidene)-5-methoxy-2H-[1,4]dioxino[2,3-h]chromene-3,9-dione (indicumin E, 1) and 7-hydroxy-6,8-dimethoxy-3-(4'-hydroxy-3'-methoxyphenyl)-coumarin (2), together with two known coumarins isofraxidin (3) and fraxetin (4), were isolated from the Solanum indicum seeds. Their structures were established on the basis of 1D and 2D spectroscopic data. Compound 1 was the rarest coumarinolignoid known to date.