You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (1S,4S,5R,8S,9R,12S,13R)-9-(4,4-dimethyl-3-oxopentyl)-1,5-dimethyl-11,14,15,16-tetraoxatetracyclo[10.3.1.04,13.08,13]hexadecan-10-one into molecular formula.
user
C21H32O6
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