You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule [(2R,4S,6S,7S,15S,16S)-6-acetyloxy-2,16-dimethyl-15-[(2-methylpropan-2-yl)oxy]-8-oxo-5-oxatetracyclo[9.7.0.02,7.012,16]octadecan-4-yl] acetate into molecular formula.
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C27H42O7
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