You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[4-[2-(1-hydroxy-2,5-dioxopyrrolidin-1-ium-1-yl)oxy-2-oxoethyl]-7,10-dimethyl-1,4,7,10-tetrazacyclododec-1-yl]acetic acid into its molecular formula.
user
C18H32N5O7+
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