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What is the molecular formula of the compound with this IUPAC name N-[3-(3-methoxyphenyl)-5,5-dioxo-3a,4,6,6a-tetrahydrothieno[3,4-d][1,3]thiazol-2-ylidene]-2-phenoxypropanamide ?
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C21H22N2O5S2
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