You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name [[(2Z,6E,10E)-3-ethenyl-7,11,15-trimethylhexadeca-2,6,10,14-tetraenoxy]-oxidophosphoryl] phosphate into its molecular formula.
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C21H33O7P2-3
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