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Name the molecular formula for the molecule established as [4-[7,18-bis(9H-fluorene-4-carbonyloxy)-8,16,17-trimethoxy-3-oxo-4-oxa-1-azapentacyclo[11.8.0.02,11.05,10.014,19]henicosa-2(11),5,7,9,12,14,16,18-octaen-12-yl]-2-methoxyphenyl] 9H-fluorene-4-carboxylate using the IUPAC nomenclature.
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C71H49NO12
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