You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 4-(2-benzyl-5,6-dimethylthieno[2,3-d]pyrimidin-4-yl)-N-(2-phenylethyl)piperazine-1-carbothioamide into its molecular formula.
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C28H31N5S2
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