1-(3,4-Dimethoxyphenyl)-2,3-bis(methoxycarbonyl)-4-hydroxy-6,7,8-trimethoxynaphthalene 104756-72-1 2,3-Naphthalenedicarboxylic acid, 4-(3,4-dimethoxyphenyl)-1-hydroxy-5,6,7-trimethoxy-, dimethyl ester TA 7552 TA-7552