You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 4-ethyl-2-[2-[4-(2-methylpropyl)piperazin-1-yl]-2-oxoethyl]sulfanylpyrido[2,3-b]pyrazin-3-one into its molecular formula.
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C19H27N5O2S
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