Variable-temperature ¹H-NMR studies on two C-glycosylflavones.

نویسندگان

  • Julia H Frank
  • Yomica L Powder-George
  • Russel S Ramsewak
  • William F Reynolds
چکیده

Two known C-glycosylflavones, swertisin and embinoidin, were isolated from the leaves of Anthurium aripoense, and characterized by room temperature 1D and 2D NMR experiments. At this temperature, the ¹H- and ¹³C-NMR spectra of these C-glycosylflavones revealed doubling of signals, which suggested the presence of two rotamers in solution. Variable-temperature (VT) ¹H-NMR studies supported this hypothesis. The T-ROESY data, in addition to the theoretical (MM2) calculations utilizing the Chem3D Pro software, confirmed the hypothesis that the two rotamers interchange via rotation about the C-glycosidic bond.

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عنوان ژورنال:
  • Molecules

دوره 17 7  شماره 

صفحات  -

تاریخ انتشار 2012