You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 19-amino-20-(2-aminoethyl)-17-(aminomethyl)-15-hydroxy-16,18,21-trioxohexatriacontane-17-sulfonic acid by IUPAC nomenclature, provide its molecular formula.
user
C39H77N3O7S
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