REACTION OF DEHYDROELLAGITANNINS WITH L-CYSTEINE METHYL ESTER
Reaction of dehydroellagitannins (e.g. 1) with L-cysteine methyl ester (5) at room temperature yielded the condensation products (e.g. 3 and 4), together with a partial hydrolysate (e.g. 2), while heating the mixture at 80 deg C afforded 4 and the hydrolysate (2) in fairly good yields.In addition, reduction of a dehydrohexahydroxydiphenoyl ester group to a hexahydroxy-diphenoyl group with thiols is also described.