You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2,12-diacetyloxy-3-hydroxy-4,9,13,17-tetramethyl-5-oxo-6-oxatricyclo[11.4.0.03,7]heptadeca-8,14-dien-16-yl) butanoate into its molecular formula.
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C28H40O9
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