New seco-anthraquinone glucosides from Rumex nepalensis.

Investigation of the N-BuOH extract of the roots of Rumex nepalensis afforded two new seco-anthraquinone glucosides, nepalensides A and B, along with nine known compounds, torachrysone ( 3), rumexoside, orientaloside, orcinol glucoside, aloesin, lyoniresinol 3 alpha- O- beta- D-glucopyranoside, (-)-epicatechin-3- O-gallate, (3,5-dimethoxy-4-hydroxyphenol)-1- O- beta- D-(6- O-galloyl) glucose, and (-)-epicatechin. Their structures were elucidated on the basis of spectroscopic methods. The possible formation of nepalensides A and B is briefly discussed.