You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 3-[(2-chlorophenyl)methyl]-2-methyl-5,6,7,8-tetrahydro-[1]benzothiolo[2,3-d]pyrimidin-4-one into molecular formula.
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C18H17ClN2OS
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