You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[[1-[1-(2-amino-3-hydroxypropanoyl)pyrrolidine-2-carbonyl]pyrrolidine-2-carbonyl]amino]pentanedioic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H28N4O8
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