You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 2-[5-[(10R)-2-(3,4-dihydroxyphenyl)-3,5-dihydroxy-4,8-dioxo-9,10-dihydropyrano[2,3-h]chromen-10-yl]-2-methoxyphenoxy]acetamide is given. What is its corresponding molecular formula?
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C27H21NO11
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