Three new stilbene derivatives, quadrangularins A, B, and C (2-4), have bee
n isolated from the stems of Cissus quadrangularis, together with four know
n ones: resveratrol, piceatannol, pallidol (1), and parthenocissine A (5).
Structure elucidation of the new compounds was achieved using 2D NMR experi
ments.