You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[(3R,6S,9S,12R)-9-[3-(diaminomethylideneamino)propyl]-6-ethyl-12-methyl-2,5,8,11-tetraoxo-3-phenyl-1,4,7,10-tetrazacyclooctadec-12-yl]-2-methylpropanamide into molecular formula.
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C31H50N8O5
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