You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named methyl 7-methyl-4-oxo-2-sulfanylidene-5-thiophen-2-yl-5,8-dihydro-1H-pyrido[2,3-d]pyrimidine-6-carboxylate by IUPAC nomenclature, provide its molecular formula.
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C14H13N3O3S2
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