You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 7-methyl-4-oxo-1-(oxolan-2-ylmethyl)-2-sulfanylidenepyrido[2,3-d]pyrimidine-5-carboxylic acid into its molecular formula.
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C14H15N3O4S
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