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Name the molecular formula for the molecule established as methyl (2R,3aR,9bR)-7-ethyl-6,9b-dihydroxy-3a,8-dimethoxy-5-oxo-2,4-dihydro-1H-benzo[e][1]benzofuran-2-carboxylate using the IUPAC nomenclature.
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C18H22O8
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