Adoligoses, oligosaccharides of rare sugars from Adonis aleppica.

Five novel tri-, tetra-, and penta-saccharides named adoligoses A-E [1-5], consisting of rare didesoxy sugars and their 3-O-Me ethers, have been isolated from Adonis aleppica. Their structures were determined by dcims and nmr measurements. Full establishment of the proton spin-systems was based on 2D nmr data, spectral simulation procedures, and force-field calculations. Sarmentose and cymarose moieties were found in both anomeric configurations and represent a major difference from alepposides A-D, biogenetically related cardenolide oligoglycosides isolated previously from the same plant source. This is the first report on complex, long-chained oligosaccharides of 2,6-didesoxy sugars found typically in cardenolide and pregnane glycosides.