Dihydrostilbene derivatives from Glycyrrhiza glabra leaves.

Four new dihydrostilbenes, alpha,alpha'-dihydro-3,5-dihydroxy-4'-acetoxy-5'-isopentenylstilbene (1), alpha,alpha'-dihydro-3,3',4'-trihydroxy-5-O-isopentenyl-6-isopentenylstilbene (2), alpha,alpha'-dihydro-3,5,3'-trihydroxy-4'-methoxystilbene (3), and alpha,alpha'-dihydro-3,3'-dihydroxy-5beta-d-O-glucopyranosyloxy-4'-methoxystilbene (4), together with seven known flavonoids, glabranin isomer, naringenin, lupiwighteone, pinocembrin 7-O-glucoside, astragalin, isoquercitrin, vicenin II, and the inositol, pinitol, were isolated from the leaves of Glycyrrhiza glabra grown in Sicily. The structures of 1-4 were elucidated by spectroscopic methods.