You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 4-[3-[(9E,11E,13E,15E)-octadeca-9,11,13,15-tetraenoyl]oxy-2-[(13E,16E,19E,22E)-pentacosa-13,16,19,22-tetraenoyl]oxypropoxy]-2-(trimethylazaniumyl)butanoate by IUPAC nomenclature, provide its molecular formula.
user
C53H87NO7
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