You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-acetyl-4-[[4-[[3-[[4-(methylamino)benzoyl]amino]phenyl]carbamoyl]phenyl]carbamoyl]cyclobutane-1,2-dicarboxylic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C30H28N4O8
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