You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 4-[2-[(9E,11E,13E)-hexadeca-9,11,13-trienoyl]oxy-3-[(8E,11E,14E,17E,20E)-tricosa-8,11,14,17,20-pentaenoyl]oxypropoxy]-2-(trimethylazaniumyl)butanoate .
user
C49H79NO7
assistant