Novel isolation of stilbenoids with enantiomeric and meso forms from a cyperus rhizome

► The isolated products were the first instance of the co-occurrence of racemates and a meso isomer, which resembles the C2 symmetrical structure. ► This was the first report that shows the occurrence of a racemate of stilbenoids in the same plant material. ► This was the first achievement of the optical separation of stilbene oligomers. ► Cyperus rhizome contained oligostilbenoids bearing blocking units of resveratrol and piceatannol. ► The determination of the absolute configuration of isolates was based on optical rotations and CD spectral properties.