You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by [(2R,3R,4R,5S,6S)-3,5-dihydroxy-2-(hydroxymethyl)-6-(1,3,6,7-tetrahydroxy-9-oxoxanthen-2-yl)oxan-4-yl] benzoate ?
user
C26H22O12
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