You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-[(1R,4R,9R,13R)-9-[4-[(2R,3S,5R,6S)-3-(2,5-dihydro-1H-imidazol-1-ium-1-yl)-5-hydroxy-6-methylpiperidin-2-yl]butyl]-4-hydroxy-1-methyl-2,14-diazabicyclo[11.3.1]heptadec-10-yn-4-yl]acetic acid by IUPAC nomenclature, provide its molecular formula.
user
C31H54N5O4+
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