You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name methyl (5R)-7-methyl-2-(2-methylpropylsulfanyl)-5-(3-methylthiophen-2-yl)-4-oxo-5,8-dihydro-3H-pyrido[2,3-d]pyrimidine-6-carboxylate into its molecular formula.
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C19H23N3O3S2
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