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system
For the molecule named 2-[(2S,2'R,6'R)-7-chloro-4,6-dimethoxy-6'-methyl-3,4'-dioxo-2'-phenylspiro[1-benzofuran-2,7'-5,6-dihydro-3H-1-benzofuran]-2'-yl]ethyl acetate by IUPAC nomenclature, provide its molecular formula.
user
C28H27ClO8
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