You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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What is the molecular formula of the molecule [(5R,7R)-7-ethyl-2,6-dioxa-9-azaspiro[4.5]decan-9-yl]-(2-propan-2-yloxypyridin-3-yl)methanone ?
user
C18H26N2O4
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