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What is the molecular formula of the molecule N-methoxy-N-methyl-4-[4-(4-nitrophenyl)-9-oxo-11-sulfanylidene-5-oxa-1,10-diazatricyclo[6.3.0.02,6]undeca-2(6),3,7-trien-10-yl]butanamide ?
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C20H18N4O6S
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