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 methyl (4S,8aS)-7-(acetyloxymethyl)-1-hydroxy-8a-methyl-2,4,5,8-tetrahydro-1H-azulene-4-carboxylate is given. What is its corresponding molecular formula?
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C16H22O5
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