You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 7-chloro-2-[(1-methylimidazol-2-yl)methylsulfanyl]-3-prop-2-enylquinazolin-4-one is given. What is its corresponding molecular formula?
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C16H15ClN4OS
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