You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (6S,9S)-4-[2-(1H-indol-3-yl)ethyl]-9,10-dimethyl-1-(2-methylpropyl)-6-(6-oxooctyl)-1,4,7,10-tetrazacyclotridecane-2,5,8,11-tetrone by IUPAC nomenclature, provide its molecular formula.
user
C33H49N5O5
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