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What is the molecular formula of the molecule 6-[(2Z)-1-benzyl-2-[(2E,4E)-5-[1'-(5-carboxypentyl)spiro[cyclohexane-1,3'-indol-1-ium]-2'-yl]penta-2,4-dienylidene]-1-methylbenzo[e]indol-3-yl]hexanoic acid ?
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C50H57N2O4+
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