Neue Untersuchung über Inhaltsstoffe der Kreuzdornrinde, IV [1] Die Hauptanthraglykoside der Rinde von Rhamnus catharticus L.: Emodin-8-O-β-gentiobiosid, -glukosid und -primverosid / A New Investigation on the Com position of Rhamni cathartici Cortex, IV [1] The Main Anthraglycosides of the Stem Bark of Rhamnus catharticus L.: Emodin-8-0-/β-gentiobioside, -glucoside and -primveroside

Abstract

From the stem bark of Rhamnus catharticus L. (purging buckthorn) the three main anthraquinone glycosides have been isolated by the new method of droplet-countercurrent-chromatography. Their structures were spectroscopically identified as em odin-8-O-β-gentiobioside, -glucoside and -primveroside. From these the primveroside is a new substance, the gentiobioside has been found for the second time in plant material. The structures were confirmed by 13C NMR spectroscopy for the first time in O-glycosides of emodin type. Especially the differences in 13C chemical shifts of the free resp. acetylated aglycones and glycosides are useful parameters for determining the position of O-glycosylation in the 1,8-dihydroxy-anthraquinone derivatives