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What is the molecular formula of the compound with this IUPAC name (5E)-3-butan-2-yl-5-[[2-(4-ethylphenoxy)-9-methyl-4-oxopyrido[1,2-a]pyrimidin-3-yl]methylidene]-2-sulfanylidene-1,3-thiazolidin-4-one ?
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C25H25N3O3S2
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