4,4'-Carbonyldiphthalic acid 3,3',4,4'-Benzophenonetetracarboxylic dianhydride Rhein 4-Benzoylbenzoic acid succinimidyl ester Anthraquinone-2-carboxylic acid Anthraquinone-2,3-dicarboxylic acid Methyl 2-benzoylbenzoate 2-Benzoylbenzoic acid 2-(4-Diethylamino-2-hydroxybenzoyl)benzoic acid 4-Bromobenzhydrol