Benzene,1,1'-ethylidenebis[4-methoxy-

4,4'-(ethane-1,1-diyl)bis(methoxybenzene)-13C6 is an intermediate for the synthesis of Bisphenol E-13C6 (B519482), which is an isotope labelled analog of Bisphenol E. Bisphenol E is a derivative of Bisphenol A (B519495) which is a monomer used for policarbonate and epoxy resins.