Isoforsythiaside, an antioxidant and antibacterial phenylethanoid glycoside isolated from Forsythia suspensa

► Isoforsythiaside, a new phenylethanoid glycoside isolated from Forsythia suspensa. ► The chemical structure of isoforsythiaside was elucidated. ► Isoforsythiaside is an analogue of forsythiaside. ► The pharmacology test showed that isoforsythiaside exhibited high activities.