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 N-ethyl-N'-(2-methyl-2-thiophen-2-ylpropyl)-2-oxa-7-azaspiro[4.4]nonane-7-carboximidamide is given. What is its corresponding molecular formula?
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C18H29N3OS
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