2,2'-dimers of aloe-emodin and chrysophanol: bianthraquinones isolated from human plasma and aromatic cascara fluid extract usp XXI

Abstract Compounds 1 and 2 isolated from human plasma were identified as 2,2'-dimers of aloe-emodin and of aloe-emodin and chrysophanol. These compounds apparently originated from consumption of a commercial Cascara preparation which contained these bianthraquinones as their glycosides. Oxydative hydrolysis of the glycosides yielded the aglycones 1 , 2 and 3 which were characterized by chemical and electron ionization mass spectrometry and by 1 H- and 13 C-NMR spectrometry.