Assignment of the 1H and 13C NMR spectra of anthraquinone glycosides from Rhamnus frangula

1H and 13C NMR chemical shifts are reported for five anthraquinone glycosides from Rhamnus frangula (Alder Buckthorn). The investigation utilized data obtained by a variety of 1D and 2D NMR techniques such as homodecoupling, NOE, J-modulated spin-echo, COSY, HSC and COLOC. Assignments were made for frangulin A and B and glucofrangulin A and B. A further compound previously thought to be a glycoside of emodin is shown to be physcion-8-O-β-D-glucoside. © 1998 John Wiley & Sons, Ltd.