You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name benzyl 1,3,7-trimethyl-2,4-dioxo-5-thiophen-2-yl-5,8-dihydropyrido[2,3-d]pyrimidine-6-carboxylate into its molecular formula.
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C22H21N3O4S
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