Compound	a-b	R1	R2	R3	R4
Piceatannol	C=C	OH	OH	OH	OH
3,5,4′-Trimethylpiceatannol	C=C	OCH3	OCH3	OH	OCH3
Trimethylresveratrol	C=C	OCH3	OCH3	H	OCH3

SCHEME R.52 Stilbene structures. (Adapted from Matsuda et al., Bioorg. Med. Chem., 12:871–4876, 2004.)