You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (10S)-2-(3,4-dihydroxyphenyl)-5-hydroxy-10-(6-methoxy-4-oxochromen-3-yl)-9,10-dihydropyrano[2,3-h]chromene-4,8-dione by IUPAC nomenclature, provide its molecular formula.
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C28H18O10
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