You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (5E)-3-butan-2-yl-5-[[2-(3,5-dimethylpiperidin-1-yl)-4-oxopyrido[1,2-a]pyrimidin-3-yl]methylidene]-2-sulfanylidene-1,3-thiazolidin-4-one by IUPAC nomenclature, provide its molecular formula.
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