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What is the molecular formula of the compound with this IUPAC name N-[2-[(5E)-2,4-dioxo-5-(thiophen-2-ylmethylidene)-1,3-thiazolidin-3-yl]ethyl]-2-methyl-3-oxo-4H-1,4-benzothiazine-6-carboxamide ?
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C20H17N3O4S3
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