Excerpted from:
Resveratrol
Ather et al.
November 1, 2007

trans-Resveratrol, also referred to as 3,5,4,'-tri-hydroxystilbene, belongs to the stilbene class of polyphenolic compounds. It exists in both cis and trans isomeric forms. In plants, it mostly exists in glycosylated piceid forms (3-O-B-D-glucosides). Other minor conjugated forms containing 1–2 methyl groups (pterostilbene), a sulfate group (trans-resveratrol-3-sulfate) or a fatty acid have also been identified. Glycosylation is known to protect resveratrol from oxidative degradation, and glycosylated resveratrol is more stable and more soluble and readily absorbed in the human gastrointestinal tract (Regev-Shoshani et al., 2003).