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What is the molecular formula of the compound with this IUPAC name 10,15-bis(2-methylpropyl)-12-oxa-20-azapentacyclo[11.7.1.02,11.04,9.017,21]henicosa-1(20),2,4,6,8,10,13(21),14,16,18-decaene ?
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C27H27NO
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