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 6-[[2-(4-methoxyphenyl)-1,3-thiazol-5-yl]methyl]-1,5,7,8-tetrahydropyrido[4,3-d]pyrimidine-2-thione into its molecular formula.
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C18H18N4OS2
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