Fractionation of a chloroform extract of Polygala paniculata (Polygalaceae) on silica gel column chromatography yielded 7-methoxy-8-(1',2'-epoxy-3'-methyl-3'-butenyl)-coumarin (1) and two coumarinic artifacts (2a-2b). The reaction of 1 with EtOH/SiO2 at room temperature for 24 hours yielded 7-methoxy-8-(1'-hydroxy-2'-ethoxy-3'-methyl-3'-butenyl)-coumarin (2a) and 7-methoxy-8-(1'-ethoxy-2'-hydroxy-3'-methyl-3'-butenyl)-coumarin (2b). The structures have been determined by spectral data, including 2D NMR experiments.
Polygala paniculata; Polygalaceae; coumarin; artifacts; NMR