You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named [4-[(2S,4R,5S)-4-hydroxy-1,2,5-trimethylpiperidin-4-yl]-2-methylbut-3-yn-2-yl] benzoate by IUPAC nomenclature, provide its molecular formula.
user
C20H27NO3
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