You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 4-[2-[(4E,7E,10E,13E,16E,19E)-docosa-4,7,10,13,16,19-hexaenoyl]oxy-3-[(9E,11E,13E,15E,17E)-henicosa-9,11,13,15,17-pentaenoyl]oxypropoxy]-2-(trimethylazaniumyl)butanoate by IUPAC nomenclature, provide its molecular formula.
user
C53H81NO7
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