((3Z,3'E)-(1,4-Phenylenebis(methaneylylidene))bis(7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl-3-ylidene))dimethanesulfonic acid 5g

((3Z,3'E)-(1,4-Phenylenebis(methaneylylidene))bis(7,7-dimethyl-2-oxobicyclo[2.2.1]heptan-1-yl-3-ylidene))dimethanesulfonic acid 5g