You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (2R,3R,4S,5S,6R)-2-[(2R,3R,4R,5R,6R)-6-(2,3-dihydroxypropoxy)-4,5-dihydroxy-2-(hydroxymethyl)oxan-3-yl]oxy-6-(hydroxymethyl)oxane-3,4,5-triol by IUPAC nomenclature, provide its molecular formula.
user
C15H28O13
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