The phenolic compounds in leaves of four Forsythia species were investigated. Phillygenin (1), (+)-pinoresinol (2), phillyrin (3), (+)-pinoresinol-β-D-glucoside (4), forsythiaside (11) and rutin (13) were isolated from Forsythia europaea DEGEN et BALD, arctigenin (5), matairesinol (6), arctiin (7), matairesinoside (8), acteoside (12) and 13 from F. ovata NAKAI, and (+)-pinoresinol monomethyl ether (9), (+)-pinoresinol monomethyl ether-β-D-glucoside (10), compounds 1-4, 12 and 13 from F. japonica MAKINO and F. giraldiana LIGEL.The distributions of lignans, lignan glucosides, phenylpropanoids and flavonoids in seven Forsythia species investigated so far (F. suspensa, F. viridissima, F. koreana, F. europaea, F. japonica, F. ovata and F. giraldiana) were compared.
