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 (5-chlorothiophen-2-yl)-[4-[1-(cyclobutylmethyl)imidazol-2-yl]piperidin-1-yl]methanone is given. What is its corresponding molecular formula?
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C18H22ClN3OS
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