You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [(6R,7R,8S)-2-hydroxy-6-methoxy-8-methyl-5-oxaspiro[3.4]octan-7-yl] 2,2-dimethylpropanoate;[(6R,7R,8S)-6-methoxy-8-methyl-2-oxo-5-oxaspiro[3.4]octan-7-yl] 2,2-dimethylpropanoate by IUPAC nomenclature, provide its molecular formula.
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C28H46O10
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