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What is the molecular formula of the compound with this IUPAC name 5,8-dichloro-2-[(4,6-dimethyl-2-oxo-3H-pyridin-3-yl)methyl]-7-(4-hydroxybutan-2-yl)-3,4-dihydroisoquinolin-1-one ?
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C21H24Cl2N2O3
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