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What is the molecular formula of the compound with this IUPAC name methyl (3R,4S)-3-ethenyl-4-[[(1S)-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-1-yl]methyl]-3,4-dihydro-2H-pyran-5-carboxylate ?
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C21H24N2O3
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