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-hydroxy-N-[(4R,5S)-5-hydroxy-9-(1H-imidazol-5-ylmethyl)-4-methyl-1-oxa-9-azaspiro[5.5]undecan-4-yl]pyridine-2-carboxamide is given. What is its corresponding molecular formula?
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C20H27N5O4
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