RESIN GLYCOSIDES .23. 2 NOVEL ACYLATED TRISACCHARIDES RELATED TO RESIN GLYCOSIDE FROM THE SEEDS OF CUSCUTA-CHINENSIS

In a continuing study on resin glycosides of crude drugs originated fr om Convolvulaceae plants, we examined the seeds of Cuscuta chinensis. Two novel acylated trisaccharides named cus-1 and cus-2 were isolated, together with a mixture of resin glycoside-like compounds. Their stru ctures were defined as alpha-L-rhamnopyranosyl-(1 --> ydroxy-2-methylb utyryl]-alpha-L-rhamnopyranosyl-(1 --> 2)-[6-O-acetyl]-D-glucopyranose and alpha-L-rhamnopyranosyl-(1 --> ydroxy-2-methylbutyryl]-alpha-L-rh amnopyranosyl-(1 --> 2)-[6-O-acetyl]-D-glucopyranose, respectively. Th ey are considered to be closely related to so-called resin glycosides in terms of structure and biosynthesis.