You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [2-[(Z)-(3',6'-dihydroxy-3-oxospiro[isoindole-1,9'-xanthene]-2-yl)iminomethyl]phenyl]boronic acid into its molecular formula.
user
C27H19BN2O6
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