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What is the molecular formula of the molecule 20-ethyl-20-hydroxy-7-methoxy-10-[(4-methylpiperazin-1-yl)methyl]-17-oxa-3,13-diazapentacyclo[11.9.0.02,11.04,9.015,21]docosa-1(22),2,4(9),5,7,10,15(21)-heptaene-14,18-dione ?
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C28H32N4O5
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