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What is the molecular formula of the compound with this IUPAC name [9-[2-carboxy-4-[[2-[[9-(2,4-dicarboxyphenyl)-3-hydroxy-6-oxoxanthen-4-yl]methylamino]-2-oxoethyl]carbamoyl]phenyl]-6-(dimethylamino)-1,2,4,4a-tetrahydroxanthen-3-ylidene]-dimethylazanium ?
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C49H43N4O12+
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