Robinobiosylation of tyrosol by seed meal from Rhamnus cathartica.

Abstract

Abstract Tyrosol robinobioside was prepared under catalysis of robinobiosidase-containing seed meal from common buckthorn Rhamnus cathartica. Robinin, a flavonoid isolated from the flowers of black locust (Robinia pseudoacacia) served as the donor of robinobiose. The glycosylation proceeded predominantly on the primary hydroxyl of tyrosol, typically yielding mixtures of isomeric glycosides in ratios of 5:1 to 8:1 with overall yields of robinobiosides higher than 20%. This is the first robinobiosylation promoted under enzymatic catalysis.