3-[(1E)-2-(4-Hydroxyphenyl)ethenyl]-5-(phenylmethoxy)-phenol-d7 is the isotope labelled analog of 3-[(1E)-2-(4-Hydroxyphenyl)ethenyl]-5-(phenylmethoxy)-phenol (H950995); the impurity C of Resveratrol (R150000) which is a minor constituent of wine, correlated with serum lipid reduction and inhibition of platelet aggregation. Resveratrol is a specific inhibitor of COX-1 and also inhibits the hydroperoxidase activity of COX-1. It has been shown to inhibit events associated with tumor initiation, promotion and progression.