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What is the molecular formula of the compound with this IUPAC name (1S,15S,20S)-19-methylsulfonyl-5,7-dioxa-13,19-diazapentacyclo[11.8.0.02,10.04,8.015,20]henicosa-2,4(8),9-trien-14-one ?
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C18H22N2O5S
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